EXTENDEND AERATION WASTE WATER TREATMENT PLANT …chuka.ac.ke/advert 17/SRP (Extended Aeration Treatment Works... · EXTENDEND AERATION WASTE WATER TREATMENT PLANT ... supplement,

CHUKA UNIVERSITY

PROPOSED SCIENCE RESEARCH

PARK – PHASE 1

EXTENDEND AERATION WASTE WATER TREATMENT PLANT (EATP)

Contract Number: CU/OPNT/53/2016-2017

Consulting Architects Consulting structural/ Civil Engineers

Conte Design Multiscope Consulting Engineers

Email: [email protected] Email: [email protected]

Consulting Quantity Surveyor Consulting Elect. &Mech. Engineers

Ecospace Consultants Mecoy Consultants LTD

Email: [email protected] Email: [email protected]

Issued by:

VICE CHANCELLOR

CHUKA UNIVERSITY

P.O. BOX 109 - 60400

CHUKA

April 2017

CHUKA UNIVERSITY

DECEMBER, 2016 Page i

TABLES OF CONTENTS

FORM OF BID, AGREEMENT AND QUALIFICATION INFORMATION ........................... 1

Bid Submission Form ....................................................................................................................2

CONDITIONS OF CONTRACT ...................................................................................................... 9

General Conditions of Contract ..................................................................................................9

Special Conditions of Contract ..................................................................................................13

Sub clause 1.1 Definitions ................................................................................................................ 13

WASTER WATER TREATMENT PLANT EVALUATION CRITERIA ................................... 35

LIST OF DRAWINGS ....................................................................................................................... 36

BILL OF QUANTITIES .................................................................................................................... 39

PREAMBLE TO THE BILLS OF QUANTITIES .......................................................................... 40

TECHNICAL DIRECTIONS .......................................................................................................... 40

TECHNICAL SPECIFICATIONS .............................................................................................44

DESIGN CALCULATIONS .......................................................................................................59

LIST OF FIGURES

Figure 1-1: Location Plan for the Sewer Reticulation and the Extended Aeration Waste Water Treatment Plant (Package). .............................. 38

CHUKA UNIVERSITY

DECEMBER, 2016 Page 1

FORM OF BID, AGREEMENT AND QUALIFICATION INFORMATION

Bidder Information Form

[The Bidder shall fill in this Form in accordance with the instructions indicated below. No alterations

to its format shall be permitted and no substitutions shall be accepted.]

1. Bidder’s Legal Name

2. In case of JV, legal name of each party:

3. Bidder’s Year of Registration:

4. Bidder’s Legal Address in Kenya

4. Bidder’s Authorized Representative Information

Name:

Address:

Telephone

Fax numbers:

2 Attached are copies of original documents of:

2.1 Articles of Incorporation or Registration of firm named in 1, above, in accordance

with ITB Sub-Clauses 4.1 and 4.2.

2.2 In case of JV, letter of intent to form JV or JV agreement, in accordance with ITB Sub-

Clause 4.1.

2.3 Copies of VAT and PIN Certificates

2.4 Copy of the Current Trade License

2.5 Tax compliance certificate

FORM OF TENDER

Tender for the -------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------- ---------

In accordance with the special specifications and the following drawings: -

-----------------------------------------------------------------------------------------------------------

To:

THE VICE CHANCELLOR

CHUKA UNIVERSITY,

P.O. BOX 109 - 60400

CHUKA.

I/we ----------------------------------------------------------------------------------------------------------------------------- --

--------------------------------------------------------------------------------------------------------------------------------------

(contractors name), under and subject to the conditions of tendering annexed hereto, hereby tender and offer to

execute and perform the works, provisions and supply all labour and materials and everything of every kind

respectively named, shown, described and / or included to ,in or to be in inferred from the general conditions of

contract, specifications and the drawings governing the contract between Chuka University and the main

contractor, and in conformity with the said specifications conditions and drawings for the lump sum named

herein below.

The undersigned agrees to be bound by and submit to the said general conditions of contract, specifications,

and priced Bills of Quantities which shall form a basis for the valuation of interim certificates and any extra or

omitted work which may from time to time be ordered by the Project Manager (P.M.)

The total sum of this tender in accordance with the specifications and/or Bills of Quantities is the lump sum of

Kenya shillings …………………………………………………………………………………………………

…………………………………………………………………………..………………………………………

Whereas it is understood that you reserve to yourself the right to agree or refuse this tender whether it is lower

or higher than any other tender or of the same amount, the undersigned agrees that the tender shall remain valid

and shall not be withdrawn within one hundred and fifty (150) days from the final date of submission of the

tenders stipulated in the advertisement or letter of invitation to tender.

And further the undersigned agrees, in the event of your acceptance of this tender, to enter into a contract as

herein before described within ten days of posting, or delivery if by hand, of Notification of Award.

Name and address of company…………………………….…………………………………………

........................................................................................................................................................

Name of person signing on behalf of company………………………………………………………..

Date ………………………….. Binding Signature …………….…………………….

Witness to signature of tender (Name) …………………………………………..

Signature ……………………………….

Address ……………………………… Date …………………………………. Page 2

CHUKA UNIVERSITY


other bid that you may receive.

Signature ……………………………………….

Name………………………………………………..

Designation………………………………………… Seal

Duly authorized to sign the bid for and on behalf

of:……………………………………………………. [Insert complete name of Bidder]

Dated on ____________ day of __________________, 20_______ [insert date of signing]

CHUKA UNIVERSITY


Appendix to Form of Tender

The following specific data for the contract shall complement, supplement, or amend the

provisions in the Instructions to Bidders (ITB). Whenever there is a conflict, the

provisions herein shall prevail over those in ITB.

Item Description Quantity/Limit Clause in FIDIC

Conditions of

Contract – Part 1

1. Amount of tender security as

bank guarantee

It is proportional to the

amount of pre-financing

requested

2. Amount of performance bond 10% of total tender price 10.1

3. Minimum amount of third

party insurance

Kshs.5,000,000 per

occurrence the number

unlimited

23.2

4. Time within which Engineer

shall issue notice to commence

the Works after the date of the

letter of acceptance.

28 days 43.1

5. Commencement date of works 30 days after receipt of

Engineer’s notice to

commence.

41.1

6. Time for completion * Calendar months 43.1

7. Amount of liquidated

damages for delay

KShs.100,000/= per day 47.1

8. Limit of liquidated damages 10% of the contract price 47.1

9. Defects liability period 12 months, after completion 49.1

10. Percentage of retention 10% of contract price 60.5

11. Mobilization advance, on

submission of bank guarantee

No advance payment shall

be made. Payments shall be

based on interim certificates

on works executed

60.7

12 Time within which payment

has to be made after delivery

of interim certificates to the

Employer

28 days 60.1

13 Appointer of arbitrator Chairman of the Engineer’s

Registration Board of Kenya

67.3

14 Rate of Interest upon unpaid

sums

2 percent points above the

Central bank of Kenya

lending rates to commercial

banks at the date of award

60.8

* To be inserted by the Tenderer

BID SECURITY

Whereas ……………………………………………………………………………………..

(Name of the tenderer)

Has submitted this tender dated ……………………………………………………. for the construction,

completion and maintenance of ………………………………………………………….

………………………………………………………………………………………………..

………………………………………………………………………………………………

KNOW ALL MEN by these present that we ………………………………………….

(Name of guarantor)

………………………………………….

(Registered address)

Are bound unto the government of Kenya (herein after called ''the employer") in the sum of Kenya shillings

(words) (As stated in the advertisement) for which payment shall well and truly be made to the said employer.

The guarantor binds itself, its successors and assignees to these presents sealed with the common seal of the

guarantor this …………………….. day of ……………..…….. 20….

THE CONDITIONS of this obligation are: -

(a) If the tenderer withdraws the tender during the period of tender validity specified in the form of

tender or: -

(b) If the tenderer, having being notified of the acceptance of its tender,

(i) Withdraws or

(ii) Fails or refuses to execute the Contract Agreement when required in accordance with

the conditions of tendering

(iii) Fails or refuses to furnish the performance bond guarantee required in accordance with

the conditions of tendering

Provided such notification shall have been made to the tenderer during the period of tender validity.

We undertake to pay the employer an amount not exceeding the above stated amount upon receipt of its first

written demand without having to substantiate its demand. Provide that in its demand the employer shall state

that the amount claimed by him is due to the occurrence of one or more of the stated CONDITIONS.

The validity of this guarantee shall be until one hundred and eighty days (180) days from date of tender

opening.

At the request of the employer the tender validity may be extended by mutual agreement between the employer

and the tenderer and we undertake to extend the validity of this guarantee accordingly, without you having to

inform us of such extension of tender validity period.

Page 5

CHUKA UNIVERSITY


Contract Agreement (sample form)

THIS CONTRACT AGREEMENT is made The……………day of…………………….20……..

BETWEEN

Chuka University incorporated under the laws of Kenya and having its principal place of

business at Chuka University (hereinafter called “the University”), and

…………………………………………………………………………………………………….name

of Contractor incorporated under the laws of Kenya and having its principal place of

business

at……………………………………………………………………………………………..address

of Contractor ] (hereinafter called “the Contractor”).

WHEREAS the University invited bids for the Construction of Chuka University

Wastewater Treatment Plant (EATP) and has accepted a Bid by the Contractor for the

construction Services in the sum of

Kshs……………………………………………………………………………………………………

……………….(in words)………………………………………(figures) (hereinafter called “the

Contract Price”).

NOW THIS AGREEMENT WITNESSETH AS FOLLOWS:

In this Agreement words and expressions shall have the same meanings as are respectively

assigned to them in the Conditions of Contract referred to.

The following documents shall constitute the Contract between the University and the

Contractor, and each shall be read and construed as an integral part of the Contract:

This Contract Agreement

Special Conditions of Contract

General Conditions of Contract

Technical Requirements (including Schedule of Requirements and Technical Specifications)

The Contractor’s Bid and original Price Schedules

The Corporation’s Notification of Award

This Contract shall prevail over all other Contract documents. In the event of any

discrepancy or inconsistency within the Contract documents, then the documents shall

prevail in the order listed above.

In consideration of the payments to be made by the University to the Contractor as

hereinafter mentioned, the Contractor hereby covenants with the University to provide the

Goods and Services and to remedy defects therein in conformity in all respects with the

provisions of the Contract.

CHUKA UNIVERSITY


The University hereby covenants to pay the Contractor in consideration of the

construction and the remedying of defects therein, the Contract Price or such other sum as

may become payable under the provisions of the Contract at the times and in the manner

prescribed by the Contract.

IN WITNESS whereof the parties hereto have caused this Agreement to be executed in

accordance with the laws of Kenya on the day, month and year indicated above.

For and on behalf of the Chuka University.

Signed:…………………………………………………………………..

Name: …………………………………..(in the capacity of Vice Chancellor)

in the presence of……………………………………………….

Designation……………………………………………………..

For and on behalf of the Contractor

Signed:…………………………………………………………………..

[signature of authorized representative(s) of the Contractor]

in the capacity of …………………………… [designation]

in the presence of……………………………. [identification of official witness]

………………………………………………….

CHUKA UNIVERSITY


Performance Security (Sample form)

[The bank, as requested by the successful Bidder, shall fill in this form in accordance with the

instructions indicated]

Tender No: ……………………………… Tender Name:. Construction of Chuka University

Extended Aeration Wastewater Treatment Plant (EATP)

Bank’s Branch or Office:…………………………………………………….complete name of

Guarantor

Beneficiary: Chuka University

PERFORMANCE GUARANTEE No.:…………………………

We have been informed that ……………………………………………….Contractor

(hereinafter called “the Contractor”) has entered into Contract No…....….. dated

…………….with you, for the Construction of Chuka University Extended Aeration

Wastewater Treatment Plant (EATP) (hereinafter called “the Contract”).

Furthermore, we understand that, according to the conditions of the Contract, a

Performance Guarantee is required.

At the request of the Contractor, we hereby irrevocably undertake to pay you any sum(s)

not exceeding ten percent of the total Contract Sum upon receipt by us of your first demand

in writing declaring the Contractor to be in default under the Contract, without cavil or

argument, or your needing to prove or to show grounds or reasons for your demand or the

sum specified therein.

This Guarantee shall expire not later than the …………day of…………… and any demand

for payment under it must be received by us at this office on or before that date.

…………………………………………………….

…………………………………………………….

[Signature(s) and seal of authorized representatives of the bank and the Contractor]

CHUKA UNIVERSITY


CONDITIONS OF CONTRACT

General Conditions of Contract

The conditions of contract comprise of two parts:

Part 1 – General Conditions of Contract

Part 2 – Conditions of Particular Application

The general conditions of contract are part 1 of the “Conditions of Contract for Works of

Civil Engineering Construction”, 4th Edition, 1987, reprinted 1992 with further

amendments, published by the Federation Internationale des Ingenieurs – Conseils (FIDIC),

and are not bound into this volume. The contractor shall be required to maintain his own

original text of the above publication in his office throughout the construction period.

The Conditions of Particular Application are included in herewith (also called the Special

Conditions of Contract) and shall have precedence over those of Part 1 (Sub Clause 5.2 of

Part 1).

CHUKA UNIVERSITY


Clause/Sub-Clause No. Description Page

1.1 Definitions ....................................................................................... 31

2.1 Engineer's Duties and Authority.................................................. 32

2.7 Duration of the Engineer's Powers............................................... 32

5.1 Language and Law........................................................................ 32

5.2 Priority of Contract Documents ................................................... 32

10.1 Performance Security...................................................................... 33

10.4 Claims against Contractor, General.............................................. 33

10.5 Cost of Securities............................................................................. 33

14.1 Programme to be Submitted ......................................................... 33

14.3 Cash Flow Estimate to be Submitted ........................................... 33

15.1 Contractor's Superintendence.........................................................33

15.2 Language Ability of Contractor's Representative........................33

16.3 Language Ability of Labour Supervisors......................................33

16.4 Employment of Local Personnel................................................... 33

16.5 Registration of Contractor's Employees ...................................... 34

19.1 Safety, Security and Protection of the Environment................... 34

20.4 Employer's Risks............................................................................. 35

21.1 Insurance of Works and Contractor's Equipment...................... 36

21.2 Scope of Cover................................................................................ 36

21.4 Exclusions......................................................................................... 36

25.1 Evidence and Terms of Insurances............................................... 36

34.2 Rates of Wages and Conditions of Labour.................................. 36

34.3 Employment of Persons in the Service of Others....................... 36

34.4 Repatriation of Labour.................................................................. 36

34.5 Housing for Labour........................................................................ 36

34.6 Health and Safety............................................................................ 37

34.7 Epidemics ....................................................................................... 37

34.8 Burial of the Dead ......................................................................... 37

34.9 Supply of Water............................................................................... 37

34.10 Arms and Ammunition....................................................................38

34.11 Festivals and Religious Customs ................................................. 38

34.12 Disorderly Conduct........................................................................ 38

34.13 Records of Labour........................................................................... 38

34.14 Trade Unions .................................................................................. 38

34.15 Observance by Subcontractors ..................................................... 38

35.2 Reporting of Accidents................................................................... 38

36.1 Quality of Materials, Plant and Workmanship............................ 39

36.6 Source of Plant and Materials ...................................................... 39

36.7 Procurement of Plant and Materials ..............................................40

41.1 Commencement of Works ............................................................ 40

42.1 Possession of Site and Access thereto.......................................... 40

42.4 Limitation of Access, Possession and Use of the Site.................. 40

44.3 Interim Determination of Extension............................................ 40

48.5 Prevention from Testing................................................................. 41

CHUKA UNIVERSITY


52.1 Valuation of Variations ................................................................. 41

52.3 Variations Exceeding 15 percent.................................................. 41

54.5 Conditions of Hire of Contractor's Equipment............... .............41

55.1 Quantities......................................................................................... 41

55.2 Omission of Rates and Prices........................................................ 42

58.2 Use of Provisional Sums ................................................................ 42

59.1 Definition of "Nominated Subcontractors"................................... 42

59.4 Payments to Nominated Subcontractors..................................... 42

60 Certificates and Payments ............................................................ 42

60.1 Monthly Statements ....................................................................... 43

60.2 Monthly Payments.......................................................................... 44

60.3 Materials and Plant for the Permanent Works............................ 45

60.4 Place of Payment............................................................................ 45

60.5 Retention Money............................................................................. 45

60.6 Payment of Retention Money........................................................ 46

60.7 Advance Payment........................................................................... 46

60.8 Time of Payment and Interest....................................................... 46

60.9 Correction of Certificates............................................................... 47

60.10 Statement at Completion........................................................... 47

60.11 Final Statement....................................................................... … 47

60.12 Discharge........................................................................................... 48

60.13 Final Certificate................................................................................ 48

60.14 Cessation of Employer's Liability.................................................. 48

63.1 Default of Contractor...................................................................... 48

63.2 Valuation at Date of Expulsion .................................................... 48

63.3 Payment after Expulsion .............................................................. 49

63.4 Assignment of Benefit of Agreement.......................................... 49

63.5 Corrupt or Fraudulent Practices .................................................. 49

65.2 Special Risks .................................................................................... 49

67.3 Arbitration........................................................................................ 49

68.1 Notice to Contractor....................................................................... 50

68.2 Notice to Employer and Engineer................................................. 50

69 Default of Employer....................................................................... 50

69.1 Default of Employer...................................................................... 50

70 Changes in Cost and Legislation................................................... 50

70.1 Price Increases ................................................................................ 50

70.2 Subsequent Legislation................................................................... 51

73 Taxation ........................................................................................... 51

73.1 Foreign Taxation............................................................................. 51

73.3 Income Taxes on Staff..................................................................... 51

74.1 Bribes................................................................................................ 51

74.2 Individuals not Personally Liable ................................................ 51

75.1 Termination of Contract for Employer's Convenience............... 52

77.1 Joint and Several Liabilities........................................................... 52

78.1 Details to be Confidential............................................................... 52

78.2 Declaration against Waiver............................................................ 52

CHUKA UNIVERSITY


79.1 Repayment....................................................................................... 52

CHUKA UNIVERSITY


Special Conditions of Contract

The following Special Conditions of Contract (SCC) also called Conditions of Particular

Application shall supplement and / or amend the General Conditions of Contract (GCC).

Whenever there is a conflict, the provisions herein shall prevail over those in the GCC.

Sub clause 1.1

Definitions

(a) (i) The Employer is:

Chuka University

P. O. Box 109 - 60400

Chuka.

(iv) The Architect is:

Conte Design Architects,

Landscape Architects and

Environmental Planners

P.O BOX 66669-00800

(v) The Civil & Structural Engineer

Multiscope Consulting Engineers

Silverpool Office Suites,Jabavu Lane, Hurlingham

P.O. BOX 12012 - 00100, Nairobi, Kenya.

Subpara. (b) (v) of Sub-Clause 1.1 is amended by the addition of the

following words at the end:

The word "Tender" is synonymous with "Bid" and the

words "Tender Documents" with "Bid Documents".

Subpara. (b) (vi) is amended by the addition of the following words:-

"Letter of Acceptance" means "Letter of Award".

Subpara. (d) (ii) is amended by the addition of the following words:-

"Taking-Over Certificate" means "Completion Certificate".

Subpara. (e) (i) is amended by the addition of the following words:-

"Contract Price" means "Contract Sum".

The Engineer shall obtain the specific approval of the Employer before

taking any of the following actions specified in Part I:

CHUKA UNIVERSITY


Sub-Clause 2.1

Engineer's Duties

and Authority

(a) approving subletting of any part of the Works under Clause 4;

(b) certifying additional cost determined under Clause 12;

(c) determining an extension of time under Clause 44;

(d) issuing a variation under Clause 51, except:

(i) in an emergency situation as reasonably determined

by the Engineer; or

(ii) if such variation would not increase the Contract Price; or,

(e) fixing rates or prices under Clause 52.

Notwithstanding the obligation, as set out above, to obtain approval, if,

in the opinion of the Engineer, an emergency occurs affecting the

safety of life or of the Works or of adjoining property, he may, without

relieving the Contractor of any of his duties and responsibilities under

the Contract, instruct the Contractor to execute all such work or to do

all such things as may, in the opinion of the Engineer, be necessary to

abate or reduce the risk. The Contractor shall forthwith comply,

despite the absence of approval of the Employer, with any such

instruction of the Engineer. The Engineer shall determine an addition

of the Contract Price, in respect of such instruction, in accordance with

Clause 52 and shall notify the Contractor accordingly, with a copy to

the Employer.

Sub-Clause 2.7

Duration of the

Engineer's Powers

Add a new Sub-Clause 2.7 as follows:-

The powers of the Engineer shall continue and be in force and

exercisable until all claims by the Contractor against the Employer and

all claims by the Employer against the Contractor have been

determined.

Sub-Clause 5.1

Language and Law

(a) The language is English.

(b) The law is that in force in the Republic of Kenya.

Sub-Clause 5.2

Priority of Contract

Documents

Delete the documents listed 1 - 6 and substitute:

(1) the Contract Agreement (if completed);

(2) the Letter of Acceptance;

(3) the Form of Tender and the Appendix to Tender;

(4) the Conditions of Contract Part II;

(5) the Conditions of Contract Part I;

(6) the Specifications and Schedules;

(7) the Drawings; and

(8) the priced Bill of Quantities.

CHUKA UNIVERSITY


Sub-Clause 10.1

Performance

Security

Replace the text of Sub-Clause 10.1 with the following:

The Contractor shall provide security for his proper performance of

the Contract to the Employer within 30 days after the receipt of the

Letter of Acceptance. The performance security shall be in the form of

a bank guarantee. The amount of the bank guarantee or the standby

letter of credit shall be as stipulated in the Appendix to Tender.

It shall be issued either by a bank located in the country of the

Employer. The performance security shall be denominated in Kshs.

Without limitation to the provisions of the preceding paragraph,

whenever the Engineer determines an addition to the Contract Price as

a result of a change in cost and/or legislation or as a result of a

variation amounting to more than 25 percent of the portion of the

Contract Price payable in a specific currency, the Contractor, at the

Engineer's written request shall promptly increase the value of the

performance security in that currency by an equal percentage.

Sub-Clause 10.5

Cost of Securities

Add a new Sub-Clause 10.5 as follows:

The cost of complying with the requirements of this Clause shall be

borne by the Contractor.

Sub-Clause 14.1

Programme to be

Submitted

The time within which the programme shall be submitted shall be 14

days.

Sub-Clause 14.3

Cash Flow Estimate

to be Submitted

The time within which the detailed cash flow estimate shall be

submitted shall be 14 days.

Sub-Clause 15.1

Contractor's

Superintendence

Add the following sentence at the end of Sub-Clause 15.1:

The Contractor shall not withdraw any of his senior staff from the Site

without the express approval of the Engineer.

Sub-Clause 15.2

Language Ability

of

Contractor's

Representative

Add the following Sub-Clause 15.2:

The Contractor's authorised representative on site shall be able to read,

write and speak English fluently

Sub-Clause 16.3

Language Ability

of Labour

Supervisors


A reasonable proportion of the Contractor's labour supervisors shall

have a working knowledge of English or the Contractor shall have

available on site at all times a sufficient number of competent

interpreters to ensure the proper transmission of instructions and

information.

CHUKA UNIVERSITY


Sub-Clause 16.4

Employment of

Local Personnel


The Contractor is encouraged, to the extent practicable and reasonable,

to employ staff and labour from sources within Kenya.

Sub-Clause 16.5

Registration of

Contractor's

Employees


The Contractor shall be responsible for making all arrangements and

registrations and shall bear all costs relative to obtaining all necessary

documents, visas, residence or other permits, identity cards etc, for his

personnel for the execution of the Works within the regulations

prevailing and applied in the Republic of Kenya.

Sub-Clause 19.1

Safety, Security and

Protection of the

Environment

Add sub-para, (d) to (g) of Sub-Clause 19.1 as follows:

(d) Notwithstanding General Conditions of Contract Clause 19.1(c), the

Contractor shall execute the Works in accordance with the

Environmental Management Plan (EMP) prepared for the particular

Works. Where an EMP does not exist, the clauses contained herein

shall form the basis of a management plan.

(e) Notwithstanding the Contractor's obligation under the above

Clause 19.1 (d), the Contractor shall:

(i) Implement all measures necessary to conserve and reduce

negative impacts on the existing environment.

(ii) Carry out all necessary works to restore the Site as far as

practicable to its original condition, all to the approval of the Engineer.

(iii) Abide by environmental performance indicators as specified in the

National Standard Regulations/ Guidelines and clarified as necessary

by the Engineer; and measure progress towards achieving

environmental objectives during execution and upon completion of the

Works.

(iv) Adhere to the activity implementation schedule agreed upon with

the Engineer to facilitate monitoring activities and adapt impact

management to changing and unforeseen conditions.

(f) Allow full access to the Site and co-operate with representatives of

the Employer, for monitoring implementation of the environmental

impact mitigation measures, who will report their findings to the

Engineer for any action.

If the Contractor fails to implement the approved Environmental Management Plan or contravenes any order as instructed by the Engineer, the Employer shall be entitled to seek legal redress through NEMA or under any appropriate Kenyan legislation.

CHUKA UNIVERSITY


Sub-Clause 20.4

Employer's Risks

Sub-Clause 20.4 is amended to read as follows: The Employer's risks

are:

(a) insofar as they directly affect the execution of the Works in Kenya:

(i) war and hostilities (whether war be declared or not), invasion, act

of foreign enemies;

(ii) rebellion, revolution, insurrection, or military or usurped power,

or civil war;

(iii) ionizing radiations, or. contamination by radioactivity from any

nuclear fuel, or from any nuclear waste from the combustion of nuclear

fuel, radioactive toxic explosive or other hazardous properties of any

explosive nuclear assembly or nuclear component thereof;

(iv) pressure waves caused by aircraft or other aerial devices travelling

at sonic or supersonic speeds;

(v) riot, commotion or disorder, unless solely restricted to the

employees of the Contractor or of his Subcontractors and arising from

the conduct of the Works;

(b) loss or damage due to the use or occupation by the Employer of

any Section or part of the Permanent Works, except as may be

provided for in the Contract;

(c) loss or damage to the extent that it is due to the design of the

Works, other than any part of the design provided by the Contractor or

for which the Contractor is responsible;

(d) any operation of the forces of nature (insofar as it occurs on the

Site) which an experienced contractor:

(i) could not have reasonably foreseen, or

(ii) could reasonably have foreseen, but against which he could not

reasonably have taken at least one of the following measures:

(A) prevent loss or damage to physical property from occurring by

taking appropriate measures, or

(B) insure against such loss or damage.

CHUKA UNIVERSITY


Sub-Clause 21.1

Insurance of Works

and Contractor's

Equipment

Add the following words at the end of sub-paras, (a) and (b) of Sub-

Clause 21.1:

", it being understood that such insurance shall provide for

compensation to be payable in Kshs. required to rectify the loss or

damage incurred."

Sub-Clause 21.2

Scope of Cover

Para, (a) of Sub-Clause 21.2 is amended by deletion of the words "from

the start of work at the Site" and by the substitution

Sub-Clause 21.3

therefore of the words:

"from the first day after the Commencement Date".

Sub-Clause 21.4

Exclusions

Sub-Clause 21.4 is amended to read as follows:

There shall be no obligation for the insurances in Sub-Clause 21.1 to

include loss or damage caused by the risks listed under Sub-Clause

20.4 paragraphs (a) (i) to (iv).

Sub-Clause 25.1

Evidence and

Terms of

insurances

Sub-Clause 25.1 is amended by inserting the words

"as soon as practicable after the respective insurances have been taken

out but in any case" before the words "prior to the start of work at the

Site"

Sub-Clause 34.2

Rates of Wages and

Conditions of

Labour

Add the following Sub-Clause 34.2:-

The Contractor shall as a minimum comply with the Labour

Regulations of Kenya and shall pay rates of wages and observe

conditions of labour not less favorable than those established for the

trade or industry where the work is carried out. In the absence of any

rates of wages or conditions of labour so established, the Contractor

shall pay rates of wages and observe conditions of labour which are

not less favorable than the general level of wages and conditions

observed by other employers whose general circumstances in the trade

or industry in which the Contractor is engaged are similar.

Sub-Clause 34.3

Employment of

Persons in the

Service of Others


The Contractor shall not recruit or attempt to recruit his staff and

labour from amongst persons in the service of the Employer or the

Engineer.

Sub-Clause 34.4

Repatriation of

Labour


The Contractor shall be responsible for the return to the place where

they were recruited or to their domicile of all such persons as he

recruited and employed for the purposes of or in connection with the

Contract and shall maintain such persons as are to be so returned in a

suitable manner until they shall have left the Site or, in the case of

persons who are not nationals of and have been recruited outside

Kenya shall have left Kenya.

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Sub-Clause 34.5

Housing for

Labour


Save insofar as the Contract otherwise provides, the Contractor shall

provide and maintain such accommodation and amenities as are

necessary for all his staff and labour, employed for the purposes of or

in connection with the Contract, including all fencing, water supply

(both for drinking and other purposes), electricity supply, sanitation,

cookhouses, fire prevention and fire-fighting equipment, cookers,

refrigerators, furniture and other requirements in connection with

such accommodation or amenities.

On completion of the Contract unless otherwise agreed with the

Employer the temporary camps/housing provided by the Contractor

shall be removed and the site reinstated to its original condition all to

the approval of the Engineer.

Sub-Clause 34.6

Health and Safety

Add the following Sub-Clause 34.6. Due precautions shall be taken by

the Contractor, and at his own cost, to ensure the safety of his staff and

labour and, in collaboration with and to the requirements of the local

health authorities, to ensure that first aid equipment and stores are

available at the camps, housing and at all places on the Site at which

work is being executed at all times throughout the period of the

Contract and that suitable arrangements are made for the prevention

of epidemics and for all necessary welfare and hygiene requirements.

The Contractor shall at all times take the necessary precautions to

protect all staff and labour employed on the Site from insect nuisance,

rats, and other pests and reduce the dangers to health and the general

nuisance caused by the same. The Contractor shall provide his staff

and labour with suitable prophylactics for the prevention of malaria,

and take steps to prevent the formation of stagnant pools of water. He

shall comply with all the regulations of the local health authorities in

these respects and shall in particular arrange to spray thoroughly with

approved insecticide all buildings erected on the Site. Such treatment

shall be carried out at least once every three months or as instructed by

the Engineer.

Sub-Clause 34.7

Epidemics


In the event of any outbreak of illness of an epidemic nature, the

Contractor shall comply with and carry out such regulations, orders

and requirements as may be made by the Government or the local

medical or sanitary authorities, for the purpose of dealing with and

overcoming the same.

Sub-Clause 34.8

Burial of the Dead


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The Contractor shall make any necessary arrangements for the

transport, to any place as required for burial, of any of his expatriate

employees or members of their families who may die in Kenya. The

Contractor shall also make any necessary arrangements for the

transport to any place in Kenya as required for burial, of any of his

local employees who may die while engaged upon the Works.

Sub-Clause 34.9

Supply of Water

Add the following Sub-Clause 34.9

The Contractor shall provide on the site an adequate supply of

drinking and other water for the use of his staff and labour.

Sub-Clause 34.10

Arms and

Ammunition


The Contractor shall not give, or otherwise dispose of to any person or

persons, any arms or ammunition of any kind or permit or suffer the

same as aforesaid.

Sub-Clause 34.11

Festivals and

Religious Customs

Add the following Sub-Clause 34.11 :-

The Contractor shall in all dealings with his staff and labour have due

regard to all recognized festivals, days of rest and religious and other

customs.

Sub-Clause 34.12

Disorderly

Conduct


The Contractor shall at all times take all reasonable precautions to

prevent any unlawful, riotous or disorderly conduct by or amongst his

staff and labour and for the preservation of peace and protection of

persons and property in the neighbourhood of the Works against the

same.

Sub-Clause 34.13

Records of Labour


The Contractor shall keep proper wages books, in English, showing the

time worked and wages paid to all tradesmen, artisans and labour

engaged on the Works, together with such other records as are

required by any Statute, Ordinance, Law, Regulation or Bye-Law in

force in the Republic of Kenya governing the employment of labour.

He shall be bound, whenever required, to produce such wages books

and other records for the inspection of any persons authorised by the

Engineer.

Should a claim be made to the Employer alleging the Contractor's

default in payment of wages, in accordance with the requirements of

this Clause, to any employees on the Works, and if proof thereof

satisfactory to the Employer is furnished, the Employer may, failing

payment by the Contractor, pay the claims out of any monies due or

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which may become due to the Contractor under the Contract.

Sub-Clause 34.14

Trade Unions


The Contractor shall recognize the freedom of his employees to be

members of trade unions.

Sub-Clause 34.15

Observance by

Subcontractors


The Contractor shall ensure that all Subcontractors engaged upon the

Works, observe all the requirements of Clause 34.

Sub-Clause 35.2

Reporting of

Accidents


The Contractor shall report to the Engineer details of any accident

involving damage to property or injury to persons occurring on the

site soonest possible after its occurrence. In the case of any fatality or

serious accident, the Contractor shall, in addition, notify the Employer

immediately by the quickest available means.

Sub-Clause 36.1

Quality of

Materials, Plant

and Workmanship

Add the following paragraph at the end of Sub-Clause 36.1:-

All Plant and materials shall be new, except as may be provided

elsewhere in the Specifications and Drawings, and manufactured,

handled, transported and installed in a workmanlike manner.

Manufacturers' warranties, guarantees, instruction sheets and parts

lists, which are furnished with Plant and material to be incorporated in

the Works, shall be delivered to the Engineer before acceptance of

those articles.

Sub-Clause 36.6

Source of Plant and

Materials


The Contractor shall provide the Engineer with a list of his sources of

Plant and materials. The list shall be submitted in a prescribed form

and be delivered to the Engineer in sufficient time to permit proper

inspection and testing of Plant and materials, to be procured from such

listed sources, in advance of their use.

The Contractor is encouraged, to the extent practicable and reasonable,

to use Plant and materials from sources, within Kenya.

Sub-Clause 36.7

Procurement of

Plant and Materials


The Contractor shall provide the Engineer with copies of all orders and

procurement schedules for the supply of Plant and materials to be

incorporated in the Works which the Engineer may require. Plant and

materials to be incorporated in the Works shall be stored in such a

manner as to ensure the preservation of their quality and suitability for

the Works, and to facilitate inspection.

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Sub-Clause 41.1

Add the following paragraphs at the end of Sub-Clause 41.1:

(1) Upon acceptance of the tender the contractor shall proceed with

due dispatch to prepare full details and particulars of major materials

which he intends to procure for the execution of the works and shall

submit these details and particulars to the engineer for approval

within 7 days of acceptance of the tender. Upon such approval, the

contractor shall within 7 days thereafter place orders with his

suppliers for the major materials or commence such other procedures

or formalities as may be required by the relevant authorities towards

such procurement.

(2) The contractor shall take all measures as shall be practicable or shall

be required by the engineer towards the earliest possible procurement

of the major materials. All orders, applications, notices,

correspondence and the like from the contractor in respect of the major

materials shall be copied to the Engineer and the Engineer's

Representative and the Contractor shall provide copies to the Engineer

and the Engineer's Representative of any correspondence, licenses,

permits, shipping documents and the like received by him which are

in any manner whatsoever related to the procurement of the major

materials within 7 days of his receipt of such correspondence and the

like.

(3) The Contractor shall commence the Works on Site within 14 days

after the receipt by him of an order in writing to this effect from the

Engineer and shall proceed with the same with due expedition and

without delay except as may be expressly sanctioned or ordered by the

Engineer or be wholly beyond the Contractor's Control.

(4) Save that notwithstanding the provisions of this clause, the

Contractor shall erect, maintain, watch and care over secure buildings

and facilities for storage of the major materials on Site subsequent to

their delivery to Site. The facilities and arrangements for such storage

and their location shall be subject to the approval of the Engineer. The

erection of such storage shall not be construed as commencement, of

works on Site.

42.1

Possession of Site

and Access thereto

Add the following paragraph at the end of Sub-Clause 42.1:

The Employer will give possession of the Site to the Contractor as

aforesaid, free of charge, and provide compensation to the owners

thereof for any crops or property standing at the date of possession.

Sub-Clause 42.4

Limitation of

Access, Possession


Possession of the Site shall be deemed to give the Contractor only such

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and Use of the Site

limited possession of it as shall be necessary to enable him, effectively,

to perform the work required under the Contract and shall not be

deemed to confer upon the Contractor a right to exclusive possession.

Sub-Clause 44.3

Interim

Determination of

Extension

Delete Sub-Clause 44.3.

Sub-Clause 48.5

Prevention from

Testing


If the Contractor is prevented from carrying out the Tests on

Completion solely by a cause for which the Employer or the Engineer

or other contractors employed by the Employer are responsible, the

Employer shall be deemed to have taken over the Works on the date

when the Tests on Completion would have been completed but for

such prevention. The Engineer shall issue a Taking-Over Certificate

accordingly. Provided always that the Works shall not be deemed to

have been taken over if they are not substantially in accordance with

the Contract.

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Sub-Clause 54.5

Conditions of Hire

of

Contractor's

Equipment

Add a final paragraph to Sub-Clause 54.5 as follows:

Within 14 days of any Contractor's Equipment being brought onto the

site, the Contractor shall notify the Engineer of the ownership of the

Equipment. For Equipment owned by the Contractor, copies of

documents of ownership shall be provided with the notification, and

for other Equipment copies of the agreement for hire thereof shall be

provided.

Sub-Clause 55.1

Quantities

Add a final paragraph to Sub-Clause 55.1 as follows:

Where any particular aspect of work or obligation of the Contract is not

specifically itemized, the costs in respect thereof shall be deemed to be

included within the available Bill of Quantities items.

Sub-Clause 55.2

Omission of Rates

and Prices

Add Sub-Clause 55.2 as follows:

Items of the Works described in the Bill of Quantities for which no rate

or price has been entered shall be considered as included in other rates

and prices in the Contract and will not be paid for separately by the

Employer.

If the Works are taken over under this Sub-Clause the Contractor shall

nevertheless carry out the Tests on Completion during the Defects

Liability Period. The Engineer shall require the Tests to be carried out

by giving 14 days notice. Any additional costs which the Contractor

may incur, in making the Tests on Completion during the Defects

Liability Period, shall be added to the Contract Price.

Sub-clause

49.4

Extension of

Defects

Liability period

For electrical

And Mechanical

Equipment

Add the following sub-clause 49.4

The defects liability period for electrical and mechanical equipment

supplied shall be extended by a period equal to the period during

which the equipment cannot be used by reason of a defect or damage.

In such a case the total length of the Defects Liability Period for

electrical and mechanical equipment shall not exceed 2 years.

Sub-clause 52.2

Engineer to Fix

Rates

Supplement sub-clause 52.2 with the following:

Provided further that no change in the rate or price for any item

contained in the Contract shall be considered unless such item

accounts for an amount of more than two (2) per cent of the Contract

Price, and the actual quantity of work executed under the item exceeds

or falls short of the quantity set out in the Bill of Quantities by more

than twenty five (25) per cent.

No change of rate for the supply items shall be adjusted whatsoever.

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Sub-Clause 58.2

Use of

Provisional

Sums

Delete Sub-Clause 58.2 and substitute:

In respect of every Provisional Sum the Engineer shall have authority

to issue instructions for the execution of work or for the supply of

goods, materials, Plant or services by the Contractor, or by a

nominated Subcontractor as hereinafter defined. Payment to the

Contractor under such Provisional Sums shall be determined as

follows:

Sub-Clause 59.1

Definition of

"Nominated

Subcontractors"

(a) For work executed by the Contractor, the Contractor shall be

entitled to be paid an amount equal to the value thereof determined in

accordance with Clause 52.

(b) For the supply of goods, materials, Plant or services by the

Contractor, the Contractor shall be entitled to be paid the actual price

of the goods, materials, Plant or services (Prime Cost), together with a

percentage adjustment on the Prime Cost. Except as may be otherwise

allowed, the adjustment shall be at the rate stated in the Appendix to

Tender, and shall be deemed to be the cost to the Contractor of

effecting and administering the Contract, and the Contractor's

overhead cost and profit in respect thereof.

(c) In the case of execution of work or supply of goods, materials,

Plant or services by a nominated Subcontractor, the Contractor shall be

entitled to an amount determined and paid in accordance with Sub-

Clause 59.4.

Sub-Clause 59.4

Payments to

Nominated

Subcontractors

Add a final sentence to Sub-Clause 59.1 as follows:

The nomination, selection or approval of a nominated Subcontractor by

the Employer or the Engineer shall not relieve the Contractor from any

liability or obligation under the Contract and he shall be responsible

for the acts, defaults and neglects of any nominated Subcontractor, his

agents, servants or workmen as fully as if they were the acts, defaults

or neglects of the Contractor, his agents, servants or workmen.

Clause 60

Certificates and

Payments

Delete the first line of paragraph (c) in Sub-Clause 59.4 and substitute:

"(c) in respect of the cost to the Contractor of assuming all of the risk

for the performance of the nominated Subcontractor, and in respect of

all other charges and profit, a sum being a percentage rate of the..."

Sub-Clause 60.2

Monthly Payments

The said statement shall be approved or amended by the Engineer

in such a way that, in his opinion,, it reflects the amounts in various

currencies due in accordance with the Contract, after deduction, other

than pursuant to Clause 47, of any sums which may have become due

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and payable by the Contractor to the Employer. In cases where there is

a difference of opinion as to the value of any item, the Engineer's view

shall prevail. In the event of amendments required, the

Contractor shall do these changes as instructed and return the

statements in the required number of copies to the Engineer. Within 28

days of receipt of the approved monthly statement referred to in Sub-

Clause 60.1, the Engineer shall issue to the Employer and the

Contractor a certificate herein called "Interim Payment Certificate",

certifying the amounts due to the Contractor. Provided that the

Engineer shall not be bound to certify any payment under this Sub-

Clause if the net amount thereof, after all retentions and deductions,

would be less than the Minimum Amount of Interim Payment

Certificates stated in the Appendix to Tender.

Notwithstanding the terms of this Clause or any other Clause of the

Contract, no amount will be certified by the Engineer for payment until

the performance security has been provided by the Contractor and

approved by the Employer.

Sub-Clause 60.3

Materials and Plant

for the Permanent

Works

With respect to materials and Plant brought by the Contractor to the

Site for incorporation in the Permanent Works, the Contractor shall (i)

receive a credit in the month in which these materials and Plant are

brought to the Site and (ii) be charged a debit in the month in which

they are incorporated in the Permanent Works, both such credit and

debit to be determined by the Engineer in accordance with the

following provisions:

(a) no credit shall be given unless the following conditions shall have

been met to the Engineer's satisfaction:

(i) the materials and Plant in the list are in accordance with the

specifications for the Works;

(ii) the materials and Plant have been delivered to the Site and are

properly stored and protected against loss, damage or

deterioration;

(iii)the Contractor's records of the requirements, orders, receipts and

use of materials and Plant are kept in a form approved by the

Engineer, and such records are available for inspection by the

Engineer;

(iv)The Contractor has submitted a statement of his cost of acquiring

the materials and Plant, together with such documents as may be

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required for the purpose of evidencing such cost; and

(v) the origin of the materials and Plant and the currencies of payment

therefore are those indicated in the Appendix to Tender.

(b) the amount to be credited to the Contractor shall be 75 percent of

the Contractor's reasonable cost of acquiring the materials and

Plant delivered to the Site, as determined by the! Engineer after

review of the documents listed in paragraph (a) (iv) above;

(c) the amount to be debited to the Contractor for any

materials and Plant incorporated into the Permanent Works

Sub-Clause 60.4

Place of Payment

shall be equivalent to the credit previously granted to the Contractor

for such materials and Plant pursuant to Sub-Clause (b) above, as

determined by the Engineer; and

Sub-Clause 60.5

Retention Money

Payments to the Contractor by the Employer shall be made in the

currencies in which the Contract Price is payable, into a bank account

or accounts nominated by the Contractor.

Sub-Clause 60.6

Payment of

Retention Money

A retention amounting to 10 percent of the amounts due and

determined in accordance with the procedure set out in Sub-Clause

60.1 (i) shall be made by the Engineer in the first and following Interim

Payment Certificates.

Upon the issue of the Taking-Over Certificate with respect to the

whole of the Works, one half of the Retention Money, or upon the

issue of a Taking-Over Certificate with respect to a Section or part of

the Permanent Works only such proportion thereof as the Engineer

determines having regard to the relative value of such Section or part

of the Permanent Works, shall be certified by the Engineer for

payment to the Contractor.

Upon the expiration of the Defects Liability Period for the Works the

other half of the Retention Money shall be certified by the Engineer for

payment to the Contractor.

Provided that, in the event of different Defects Liability Periods being

applicable to different Sections or parts of the Permanent Works

pursuant to Clause 48, the expression "expiration of the Defects

Liability Period" shall, for the purposes of this Sub-Clause, be deemed

to mean the expiration of the latest of such periods.

Provided also that if at such time, there shall remain to be executed by

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the Contractor any work ordered, pursuant to Clauses 49 and 50, in

respect of the Works, the Engineer shall be entitled to withhold

certification until completion of such work of so much of the balance of

the Retention Money as shall, in

the opinion of the Engineer, represent the cost of the work remaining

to be executed.

Sub-Clause 60.8

Time of Payment

and Interest

The amount due to the Contractor under any Interim Payment

Certificate issued by the Engineer pursuant to this Clause, or to any

other term of the Contract, shall, subject to Clause 47, be paid by the

Employer to the Contractor within 28 days after the Contractor's

monthly statement has been received by the Employer or, in the case of

the Final Certificate pursuant to Sub-Clause 60.13, within 84 days after

the agreed Final Statement and written discharge have been submitted

to the Engineer for certification.

In the event of failure of the Employer to make payment within the

times stated, the Employer shall pay to the Contractor simple interest

at the rate stated in the Appendix to Tender upon all sums unpaid

from the date upon which the same should have been paid, in the

currencies in which the payments are due.

Sub-Clause 60.9

Correction of

Certificates

The Engineer may by any Interim Payment Certificate make any

correction or modification in any previous Interim Payment Certificate

which has been issued by him, and shall have authority, if any work is

not being carried out to his satisfaction, to omit or reduce the value of

such work in any Interim Payment Certificate.

Sub-Clause 60.10

Statement at

Completion

Not later than 21 days after the issue of the Taking-Over Certificate in

respect of the whole of the Works, the Contractor shall submit to the

Engineer a Statement at Completion with supporting documents

showing in detail, in the form approved by the Engineer,

(a) the final value of all work done in accordance with the Contract up

to the date stated in such Taking-Over Certificate;

(b) any further sums which the Contractor considers to be due; and

(c) an estimate of amounts which the Contractor considers will become

due to him under the Contract.

Estimated amounts shall be shown separately in such Statement at

Completion. The Engineer shall certify payment in accordance with

Sub-Clause 60.2.

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Sub-Clause 60.11

Final Statement

Not later than 21 days after the issue of the Defects Liability Certificate

pursuant to Sub-Clause 62.1, the Contractor shall submit to the

Engineer for consideration a draft final statement with supporting

documents showing in detail, in the form approved by the Engineer,

(a) the value of all work done in accordance with the Contract; and

(b) any further sums which the Contractor considers to be due to him

under the Contract.

If the Engineer disagrees with or cannot verify any part of the draft

final statement, the Contractor shall submit such further information as

the Engineer may reasonably require and shall make such changes in

the draft as may be agreed between them. The Contractor shall then

prepare and submit to the Engineer the final statement as agreed (for

the purposes of these Conditions referred to as the "Final Statement").

If, following discussions between the Engineer and the Contractor and

any changes to the draft final statement which may be agreed between

them, it becomes evident that a dispute exists, the Engineer shall issue

to the Employer an Interim Payment Certificate for those parts of the

draft final statement which are not in dispute. The dispute shall then

be settled in accordance with Clause 67. The Final Statement shall be

agreed upon settlement of the dispute.

Sub-Clause 60.12

Discharge

Upon submission of the Final Statement, the Contractor shall give to

the Employer, with a copy to the Engineer, a written discharge

confirming that the total of the Final Statement represents full and final

settlement of all monies due to the Contractor arising out of or in

respect of the Contract. Provided that such discharge shall become

effective only after payment due under the Final Certificate issued

pursuant to Sub-Clause 60.13 has been made and the performance

security referred to in Sub-Clause 10.1 has been returned to the

Contractor.

Sub-Clause 60.13

Final Certificate

Within 28 days after receipt of the Final Statement, and the written

discharge, the Engineer shall issue to the Employer (with a copy to the

Contractor) a Final Certificate stating

(a) the amount which, in the opinion of the Engineer, is finally due

under the Contract, and

(b) after giving credit to the Employer for all amounts previously

paid by the Employer and for all sums to which the Employer is

entitled under the Contract, other than Clause 47, the balance, if any,

due from the Employer to the Contractor or from the Contractor to the

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Employer as the case may be.

Sub-Clause 60.14

Cessation of

Employer's

Liability

The Employer shall not be liable to the Contractor for any matter or

thing arising out of or in connection with the Contract or execution of

the Works, unless the Contractor shall have included a claim in respect

thereof in his Final Statement and (except in respect of matters or

things arising after the issue of the Taking-Over Certificate in respect

of the whole of the Works) in the Statement at Completion referred to

in Sub-Clause 60.10.

Sub-Clause 63.1

Default of

Contractor

Delete the last paragraph of this Sub-Clause and substitute the

following:

"... then the Employer may, after giving fourteen days' notice in

writing to the Contractor, enter upon the Site and expel the Contractor

there from without thereby voiding the Contract, or releasing the

Contractor from any of his obligations or liabilities under the Contract,

or affecting the rights and powers conferred on the Employer or the

Engineer by the Contract, and may himself complete the Works or may

employ any other contractor to complete the Works.

The Employer or such other contractor may use for such completion so

much of the Contractor's Equipment, Plant, Temporary Works and

materials, which have been deemed to be reserved exclusively for the

execution of the Works, under the provisions of the Contract, as he or

they may think proper, and the Employer may, at any time, sell any of

the said Contractor's Equipment, Temporary Works and unused Plant

and materials and apply the proceeds of sale in or towards the

satisfaction of any sums due or which may become due to him from

the Contractor under the Contract."

Sub-Clause 63.2

Valuation at Date

of Expulsion

Modify the heading of Sub-Clause "63.2 by substituting "Valuation at

Date of Expulsion" for "Valuation at Date of Termination". In Sub-

Clause 63.2, delete the word "termination" on the second and fifth lines

and substitute: "expulsion".

Sub-Clause 63.3

Payment after

Expulsion

Modify the heading of Sub-Clause 63.3 by substituting "Payment after

Expulsion" for "Payment after Termination". In Sub-Clause 63.3, delete

the words "terminates the Contractor's employment" on the first line

and substitute "shall enter and expel the Contractor".

Sub-Clause 63.4

Assignment of

Benefit of

Agreement

In Sub-Clause 63.4, delete the word "termination" on the second line

and substitute:" expulsion".

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Sub-Clause 63.5

Corrupt or

Fraudulent

Practices

Add Sub-Clause 63.5:

If in the judgement of the Employer the Contractor has engaged in

corrupt or fraudulent practices, in competing for or in executing the

Contract, then the Employer may, after having given 14 days notice to

the Contractor, terminate the Contractor's employment under the

Contract and expel him from the Site, and the provisions of Clause 63

shall apply as if such expulsion had been made under Sub-Clause 63.1.

For the purpose of this Sub-Clause :

"corrupt practice" means the offering, giving, receiving or soliciting of

anything of value to influence the action of a public official in the

procurement process or in contract execution.

"fraudulent practice" means a misrepresentation of facts in order to

influence a procurement process or the execution of a contract to the

detriment of the Borrower, and includes collusive practice among

Tenderers (prior to or after Tender submission) designed to establish

Tender prices at artificial and non-competitive levels and to deprive

the Borrower of the benefits of free and open competition."

Sub-Clause 65.2

Special Risks

Sub-Clause 65.2 is amended to read as follows:

The Special Risks are the risks defined under paragraph (a), sub-

paragraphs (i) to (v) of Sub-Clause 20.4.

Sub-Clause 67.3

Arbitration

Delete in lines 6 to 8, of Sub-Clause 67.3 the words from "unless

otherwise" to "under such Rules" and add after the words "shall be

finally settled" in line 6 the following:

"in Kenya in accordance with the provisions of the Arbitration Act of

the Laws of Kenya or any other enactment replacing or modifying the

same for the time being in force, by a single arbitrator appointed by the

Chairman of the Engineer's Registration Board of Kenya on application

by either party."

Sub-Clause 68.1

Notice to

Contractor

Delete the text of Sub-Clause 68.1 and substitute the following:-

The Contractor shall maintain a physical and a postal address in the

Republic of Kenya, for the duration of the Contract.

The Contractor shall notify the Employer and the Engineer, in writing,

of the address of the office and of any change thereof and the

Employer and the Engineer shall not be bound to any change of

address until it has been so notified. The said offices shall be deemed

to be the domicile in Kenya of the Contractor and shall be kept open at

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all reasonable hours during the above mentioned period to receive

instructions, notices, processes or other communications, unless

otherwise agreed in writing, between the Employer and the Engineer

and the Contractor.

All notices and other communications that are left against signature at,

or sent by registered post to, the said offices shall be deemed to be

validly served upon the Contractor. Every letter sent by registered post

shall be deemed to have arrived in due course of post until the

contrary is proved.

The Contractor shall also maintain an office at the Site which shall be

kept open during normal working hours to receive instructions,

notices, or other communications.

Sub-Clause 68.2

Notice to Employer

and Engineer

For the purposes of this Sub-Clause, unless otherwise stated in writing

by the Engineer, notices to both the Employer and Engineer shall be

sent to:

Vice Chancellor

Chuka University

P. O. Box 109 - 60400

Chuka.

Clause 69

Default of

Employer

In Sub-Clause 69.1, 69.4 and 69.5, substitute "Sub-Clause 60.8" for "Sub-

Clause 60.10".

Sub-Clause 69.1

Default of

Employer

In Sub-Clause 69.1 (a), substitute "56 days" for "28 days".

Delete Sub-Clause 69.1 (d).

Clause 70

Changes in Cost

and Legislation

Delete Clause 70 in its entirety and substitute the following:-

Sub-Clause 70.1

Price Increases

The rates and prices entered by the tenderer shall be deemed to

include for the cost of any price increases that may affect the Works

and which may occur during the validity of the Tender, and any

extended period of validity thereof, and during the execution of the

Works.

Sub-Clause 70.2

Subsequent

Legislation

If, after the date 28 days prior to the latest date for submission of

tenders for the Contract there occur in Kenya changes to any National

or State Statute, Ordinance, Decree or other Law or any regulation or

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by-law of any local or other duly constituted authority, or the

introduction of any such State Statute, Ordinance, Decree, Law,

regulation or by-law which causes additional or reduced cost to the

Contractor in the execution of the Contract, such additional or reduced

cost shall, after due consultation with the Employer and the

Contractor, be determined by the Engineer and shall be added to or

deducted from the Contract Price and the Engineer shall notify the

Contractor accordingly, with a copy to the Employer.

Clause 73

Taxation

Sub-Clause 73.1

Foreign Taxation

The prices tendered by the Contractor shall include all taxes, duties

and other charges imposed outside Kenya on the production,

manufacture, sale and transport of the Contractor's Equipment, Plant,

materials and supplies to be used on or furnished under the Contract,

and on the services performed under the Contract.

Sub-Clause 73.3

Income Taxes on

Staff

The Contractor's staff, personnel and labour will be liable to pay

personal income taxes in Kenya in respect of such of their salaries and

wages as are chargeable under the laws and regulations for the time

being in force, and the Contractor shall perform such duties in regard

to such deductions thereof as may be imposed on him by such laws

and regulations.

Sub-Clause 74.1

Bribes

If the Contractor, or any of his Subcontractors, agents or servants gives

or offers to give to any person any bribe, gift, gratuity or commission

as an inducement or reward for doing or forbearing to do any action in

relation to the Contract or any other contract with the Employer, or for

showing or forbearing to show favour or disfavour to any person in

relation to the Contract or to any other contract with the Employer,

then the Employer may enter upon the Site of the Works and expel the

Contractor and the provisions of Clause 63 hereof shall apply as if such

entry and expulsion had been made pursuant to that Clause.

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Sub-Clause 75.1

Termination of

Contract for

Employer's

Convenience

The Employer shall be entitled to terminate the Contract at any time

for the Employer's convenience after giving 21 days prior notice to

the Contractor, with a copy to the Engineer. In the event of such

termination, the Contractor:

(a) shall proceed as provided in Sub-Clause 65.7 and

(b) shall be paid by the Employer as per Sub-Clause 65.8.

Sub-Clause 77.1

Joint and Several

Liability

If the Contractor is a joint venture of two or more persons, all such

persons shall be jointly and severally bound to the Employer for the

fulfilment of the terms of the Contract and shall designate one of

such persons to act as a leader with authority to bind the joint

venture. The composition or the constitution of the joint venture shall

not be altered without the prior consent of the Employer.

Sub-Clause 78.1

Details to be

Confidential

The Contractor shall treat the details of the Contract as private and

confidential, save insofar as may be necessary for the purposes

thereof, and shall not publish or disclose the same or any particulars

thereof in any trade or technical paper or elsewhere without the

previous consent in writing of the Employer or the Engineer. If any

dispute arises as to the necessity of any publication or disclosure for

the purpose of the Contract the same shall be referred to the decision

of the Employer whose award shall be final.

Sub-Clause 78.2

Declaration against

Waiver

The condoning by the Employer of any breach or breaches by the

Contractor, or an authorized subcontractor, of any of the stipulations

and conditions contained in the Contract shall in no way prejudice or

affect or be construed as a waiver of the Employer's rights, powers

and remedies under the Contract in respect of any other breach or

breaches as aforesaid.

Sub-Clause 79.1

Repayment

Any payment for account of the Employer shall be made to

Vice Chancellor

Chuka University

P. O. Box 109 - 60400

Chuka.

WASTER WATER TREATMENT PLANT EVALUATION CRITERIA Bid evaluation will be in three stages namely: -

1. Mandatory requirements

2. Technical evaluation

3. Financial evaluation

4. Recommendation

A. Mandatory requirements

The mandatory conditions to be complied with are: -

a) Form of tender (properly filled)

b) Bid security with proper validity and as per sample provided

c) Class of registration with National Construction Authority

d) Tax compliance certificate

e) Must have completed a similar construction work of at least 10 million tender sum

f) Must have an annual turnover of at least 2 million (read from latest audited annual accounts)

g) The document must be properly serialised on all pages and total number of pages clearly stated

ii) A company shall fulfil all the seven conditions above in order to proceed to technical evaluation.

iii) Any company that does not fulfil any of the above conditions shall be disqualified from further

evaluation at this stage.

Technical evaluation

The bidder must attach the following, at the time of submission, in order to be considered technically responsive: -

1. Audited accounts of 2015 showing a fixed asset base of more than Kenya shillings five million

2. The (CV) Curriculum Vitae of the Lead Technical Expert including appropriate certificates showing relevant

technical qualification.

3. Completion certificates / recommendation for at least three similar project undertaken and completed successfully.

4. Attach proof of availability of at least two million Kenya shillings in liquid assets working capital (Bank credit line,

assets which can be quickly liquidated, bank statements etc.).

5. The brochures and / technical data for the lift will be analyzed in relation to:–

a) Adherence to minimum technical specifications for the Waste Water Treatment Plant attached here in.

b) All supporting calculations

c) Ease of availability of spares in the Kenyan Market.

d) Bidder must demonstrate how he will carry out the training of the client’s personnel for routine maintenance of the plant

e) Availability of qualified personnel for maintaining the machines.

f) The minor and major service intervals of the machines

g) Operation and maintenance cost of the supplier’s plant model (energy cost, chemical cost, and attendance)

h) Recommendations from satisfied users in the Kenyan market of the make and type of Waste Water Treatment

Plant recommended in the brochure.

The bidders who meet all the above five requirements will proceed to financial analysis.

C. Financial evaluation

The financial bids will be ranked from lowest to highest bid as per the total tender sum.

D. Recommendation The bidder with the lowest combination of initial investment; operation and maintenance cost

during the design life (20years) of the project will be recommended for award of this tender if the bid price is within the

prevailing market price.

Page 35

CHUKA UNIVERSITY


LIST OF DRAWINGS

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List of Drawings

Drawing Number Description

MCE-153-SRL-001 Location Plan for the Sewer Reticulation and the Extended Aeration Waste Water Treatment Plant (Package).

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Figure 1-1: Location Plan for the Sewer Reticulation and the Extended Aeration Waste Water Treatment Plant (Package).

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BILL OF QUANTITIES

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PREAMBLE TO THE BILLS OF QUANTITIES

TECHNICAL DIRECTIONS

The preferred waste water treatment plant shall accommodate or have the following parameters:

Should be economical to space as practically possible, The design life of the plant should not be less than 30 years, Odors free treatment process, WWTP should handle a design capacity of 285 m3/day, but the plant should be

configured to operate at any discharge below this capacity i.e. should be adjustable to operate at a rate lower than design capacity,

The influent to the plant are from the following precincts

84m3/day from science biological and physics laboratories 36m3/day from administration block 110m3/day from students hostels 10 m3/day from food science laboratories Future projected load of 45m3/day

The supplier MUST provide us with all the design calculation justifying the sizes of various components of treatment works components i.e. blowers capacities, pumps capacity, sizes of chambers e.t.c.

Detailed schematic civil and structural drawings MUST accompany the quotation to enable us cost the civil and structural works,

Supplier MUST clearly state the operation and maintenance cost per annum when the plant is operating at full capacity, distinguishing chemical costs or any other associated cost,

Note the design of the plant will start from the outfall of our last manhole which will have invert depth of not more than 1 m

The location of the site is generally flat; however, the discharge point will be over 4 m lower than the site elevation hence the design of the effluent discharge system from the plant will utilize gravity.

The effluent should be dischargeable to the environment,

INFLUENT QUALITY The proposed effluent treatment plant was designed based on following types of influents: Estimate influent quality from similar case studies.

Sr. No. Parameter Unit Range 1 PH pH Scale 6.5 3 TDS mg/L 1520-1620 TSS mg/L 460 4 BOD (20C) mg O2/l 250-400

5 COD mg O2/l 400-800

(These are estimates and therefore they should not be used entirely to design the system, hence the supplier is expected to have prior experience in working in projects of similar condition)

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BILLS OF QUANTITIES FOR ELECTRO-MECHANICAL INSTALLATIONS # Description Unit Quantity Rate (Kshs) Amount

(Kshs) 1 Supply and install suitable equipments

housing

Nr 1

2 Supply and install suitable Blowers of the following characteristics Qmax=210 m3air /hr; Power 5 HP with its silencer

Nr 2

3 Supply and install suitable Blowers of following characteristics Qmax=545 m3air /hr; Power 10 HP with its silencer

Nr 2

4 Supply and install suitable blower drive systems

Nr 4

5 Supply and install suitable blower motor of 5hp 380v 3ph 50hz

Nr 2

6 Supply and install suitable blower motor of 10hp 380v 3ph 50hz

Nr 2

7 Supply and install control panels for the pumps which must include timers, Automatic alteration and flow control packages

Nr 1

8 Supply and install control panels for the blowers which must include timers and Automatic alteration

Nr 1

9 Supply and install suitable chlorinator model for chlorine tablet.

Nr 1

10 Supply and install galvanized 1.8mx 0.3m x0.9 m fine screen

Nr 1

11 Supply and install suitable package of MBBR media balls

Nr 1

12 Supply and install suitable MBBR media screens

Nr 6

13 Supply and install Air seal diffusers

Nr 120

14 Supply and install airlift surface skimmer

Nr 1

15 Supply and install sludge holding supernatant pump 1 HP, manual controlled

Nr 1

16 Supply and install 1HP, Qmax of 14.5m3/hr and Hmax 5.0m Sludge return pump, time controlled,

Nr 2

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# Description Unit Quantity Rate (Kshs) Amount (Kshs)

17 Supply and install 0.5 Horse power, Qmax of 7.13m3/hr and Hmax 5.0m Sludge return pump, time controlled

Nr 2

18 Supply and install all plumbing works including tees, bushes, elbows & sockets valves, GI pipes or any other suitable materials and any other fitting which will ensure the plant works efficiently to the Engineers satisfaction

Lump sum

1

19 Supply and install suitable effluent filtration unit with its media

Nr 1

20 Carry out complete biological and chemical test for monitoring the effluent with supervision from the Engineer

Nr 3

21 Supply Grease gun & grease and squeeze for maintenance tools

Nr 1

22 1 (one) year warranty and free Service of the plant. Rate to include for 3 months training of clients’ staff

%

23 Allow 10% contingencies for the whole amount

% 1 10

Total amount Exclusive of VAT

Total VAT Amount

Total amount Inclusive of VAT

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PERFORMANCE GUARANTEE: The Waste Water Treatment Plant should be capable of treating the above influent to the effluent quality acceptable for discharge into the environment, based on the third schedule of NEMA regulations. The electro-mechanical quote should be inclusive of all necessary government taxes, duties and levies including VAT in accordance with the laws of Kenya and the Client shall not reimburse any amount paid in this context. PAYMENT TERMS The payment schedule should be broken down into the following percentages:

% payable at time of placing the order

% payable upon delivery of plant to site.

% on testing and commissioning of plant

% payable at end of defects liability Period - 6months

This system will cost Kenya Shillings (amount in figures) (Amount in words) inclusive of VAT

NOTE:

The Extended Aeration Treatment Plant (Package) Contractor will only install the

ELECTRO-MECHANICAL components of these works while all other civil and structural

works will be done by the main contractor.

CHUKA UNIVERSITY


TECHNICAL SPECIFICATIONS EXTENDEND AERATION WASTE WATER TREATMENT PLANT FOR CHUKA UNIVERSITY-THARAKA NITHI COUNTY

SECTION-01: BASIS OF DESIGN

The capacity/ rating of pumps and equipment etc. shall hold well for the capacity of 250-400

cum / day i.e. 250-400 KLD and shall be good for meeting the treated parameters

requirement as follows as per the NEMA and World Health Organisation (WHO)

regulations.

SECTION-02: SEWAGE TREATMENT PLANT

1.0 GENERAL

The sewage treatment plant (EATP) system outlined in this section specifies the system

design, manufacture, supply and installation of a standard Extended Aeration Wastewater

treatment (Package) System.

The work shall be carried out in a manner consistent with standards of specifications as

applicable. The Contractor shall take into account all site conditions in designing the system

and selecting the equipment. The Contractor shall be responsible for engaging an EATP

specialist to perform the system design and obtain approval from relevant Authorities and

Project Architect/ Project Architect’s representative. A qualified and experienced Engineer

shall be engaged for the system design, preparation of system proposal submission,

obtaining approval and site supervision.

The Contractor shall perform the system design based on the criteria/data and component

technical requirements specified in this section/drawings and the local Authorities’

regulation/requirement.

The Contractor shall furnish system which comprises products of manufacturers who have

designed and made these associated products for a period of at least five years.

The Contractor shall submit complete catalogue information, design calculation and

samples complete with full technical data and shop drawings for the entire system, test

certificates, etc. for acceptance prior to commencement of installation. The Contractor shall

submit analytical test reports of influent water samples and treated (effluent) water samples

after the commissioning or after the system is put into operation or as required by the

Project Engineer/their representative. The scope of work under this contract will include

assisting Project Engineer/their representatives to obtain necessary consent to operate from

local pollution control government authority.

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2.0 DESIGN CRITERIA

2.1 It shall be the Contractor’s responsibility to ensure the quality of the treated effluent to

comply with the NEMA regulations on waste water discharge requirement and the

following characteristics, whichever is stringent.

Estimate influent quality from similar case studies. Sr. No. Parameter Unit Range

1 PH pH Scale 6.5

3 TDS mg/L 1520-1620

TSS mg/L 460

4 BOD (20C) mg O2/l 250-400

5 COD mg O2/l 400-800

(These are estimates and therefore they should not be used entirely to design the system, hence the supplier is

expected to have prior experience in working in projects of similar condition)

2.2 Description of Process

The Sewage Treatment Plant shall be modular and packaged type installed on levelled

ground. The treatment process shall comprise the following stages:

Physical treatment: coarse bar-screening

Primary treatment: auto coarse bar-screen

Grease Trap Oil and Grease separation

Equalization tank: flow equalization with air Mixing

Flow measurement: flow meter

Nitrates removal Required

Biological treatment: MBBR as suitable to waste water quality

Final sedimentation: final settling tank with scraper

Disinfection: chlorination system : system with dosage control

Digester: aerobic digestion with individually retrievable air diffuser system.

Water reclamation: Partially tertiary filtration and sterilization for irrigation, cooling

tower makeup purpose and Flushing. Balance water quantity meeting irrigation

standards but with sterilization.

Sludge disposal: sludge chemical conditioning, disinfecting, dewatering and

disposal.

The Extended Aeration Treatment Plant (Package) Contractor will only install the

ELECTRO-MECHANICAL components of these works while all other civil and structural

works will be done by the main contractor.

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2.3 Performance Criteria of the Plant

Raw sewage will be brought into the last manhole of the sewerline. The Contractor shall

make arrangements to receive sewage from this point to the treatment plant for treatment

process.

The treatment plant shall be designed to treat the following basic characteristic expected in

the raw sewage. The waste water characters are based upon sampling done at project site

and for indicative purpose only. However, it will be entire responsibility of contractor’s to

reestablish the Wastewater characters and design system accordingly.

Description Details:

Estimated daily flow 285m3/ day

Discharge period 20 hrs./ day

PH 6.5-8.50

Influent BOD5 concentration 250-400 mg/l

Influent chemical oxygen demand 600-800 mg/l

Influent suspended solids(TSS) 200-600 mg/l

Oil and Grease 7-25 mg/l

E Coli Present

Faecal Coliform 600-1100 No/100ml

These are tentative indicative figures; however, as a specialist in the field, contractor may

envisage the raw sewage characteristic for waste water. It will be entirely contractor’s

responsibility to confirm the waste water characters.

Contractor to submit his confirmation on the treatment parameter considered as an

Annexure. The plant shall be capable of treating effluent to the following standards:

2.4 Process Description

The Main Contractor shall construct (civil and structural components) of Sewage

Treatment Plant to receive continuous sewage inflow at last manhole located near

EATP area as indicated on site plan. The ease of maintenance and operation is of

utmost importance in the design of Sewage Treatment Plant. The design of the

Sewage Treatment Plant shall be of suitable technology based; it can be installed

within the allocated space and shall be subject to the approval of the Project

Engineer/their representative

The plant will be housed on the ground, except for raw sewage and treated water

tanks. The required civil works like foundations etc shall be excluded in the scope

of work of EATP contractor.

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These will be general components, for the purpose of indication, but not limited to,

the EATP plant.

2.4.1 Inlet Screen Chamber

Raw sewage shall flow into the inlet screen chamber by gravity. Large solids

particles shall be intercepted by a fine step screen. A manual screen shall be

installed in parallel with the screw screen as a standby screen when the step screen

is under maintenance. It will not be part of the EATP contractor to execute but will

be designed by him.

Bar Screen

A bar screen having 20 mm opening shall be inserted in a bar screen chamber (in

RCC) at the inlet to the equalization tank. This screen will act as a guard and trap

any large objects which may otherwise block the pumps. The screenings shall be

removed by means of a manual rake arm for disposal. It will not be part of the

EATP contractor to execute but will be designed by him.

2.4.2 Aeration Tank

Sewage shall be retained in the aeration tank for a minimum of 24 hours and

subjected to biochemical oxidation by fine bubbles aeration. It will not be part of the

EATP contractor to execute but will be designed by him.

Equalization Tank

The screened effluent will overflow into an equalization tank. The equalization tank

is sized for a retention time of 6-8 hours. Since the generation of raw sewage is not

uniform (typically peaking in morning and evening hours), this tank buffers the

flow and ensures that the effluent inlet quantity and characteristics to the sewage

treatment plant is uniform.

To avoid settlement of solids and septicity in the tank, aeration is provided through

coarse bubble aeration grid consisting of perforated PVC pipes, individually

retrievable. The perforations are designated to give uniform air distribution through

the air grid. All plumbing works shall be part of the EATP contractor to design and

execute.

2.4.3 Clarifier Tank

The sewage after bio-oxidation shall enter the rectangular flat bottom sedimentation

tank where the sludge effectively settles to the tank bottom. The clear effluent shall

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weir into the chlorination chamber and/or ultraviolet chamber.

The activated sludge collected in the sludge tank shall be returned to the aeration

tank for further oxidation of the incoming organic matter by means of automatic

siphoning / pumping. Excessive sludge shall be wasted in the sludge holding tank.

Any scum formed on the surface of the clarifier tanks shall be returned to the

aeration tank by automatic siphoning / pumping. It will not be part of the EATP

contractor to execute but will be designed by him.

Chlorination Tank

Chlorine tablets shall be installed in the chamber and dissolve by the flowing

effluent. The effluent shall be retained in the baffle walled chlorine tank for a

minimum of 30 minutes for effective disinfection prior to discharge.

The equalization tank shall be designed to provide a minimum storage of 4 hours at peak

flow while pumping. Two submersible pumps (duty and standby) as per schedule shall be

provided with level switch control and automatic cut-in of the standby unit.

An aeration system similar to the extended aeration tank shall be provided for mixing and

aerating the sewage.

It will not be part of the EATP contractor to execute but will be designed by him.

3.5 Sludge Collectors

The sludge collectors serve to scrap the settled sludge to the sludge pump pit and a skimmer shall collect the scum. Each shall be of mechanical drivers for full automatic operation. All components such as chain, sprocket, etc. inside the tank shall be made of non-metallic material. It will not be part of the EATP contractor to execute but will be designed by him.

3.6 Sewage Pumps

Working and standby sewage pumps shall be provided. Contractor shall provide the

pumping arrangements for sewage collected near collection chamber near EATP. Each shall

be of submersible type guide base to facilitate case of removal, lift chain and automatic

discharge connection. Pump casing and impeller shall be of cast iron material. Shaft shall be

of stainless steel material. All sizing of pumps shall be part of the EATP contractor to design

and execute.

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3.8 Final Settling Tank

Settling tanks shall include baffles to prevent short circuiting. Sludge withdrawal shall be

by means of rotating sludge collectors. Four submersible sludge pumps shall be installed in

the hopper bottom at inlet side of the settling tank for periodic sludge removal. It will not

be part of the EATP contractor to execute but will be designed by him

3.9 Tertiary Treatment

The tertiary treatment plant shall comprise of the pressure sand filters, activated carbon

filters and out to inward entry sewage water designed membrane filtration system. This

shall be sized to accommodate 100% of the effluent discharge flow rate and shall achieve

the performance as outlined and described in Design Criteria.

Details of the equipment layout proposal shall be submitted for review by the Project

Manager with tender documents.

The filters will be added in phases as demand arises and system shall be capable to add

with additional tertiary filtration units without disturbing the existing operations of system.

All sizing of tertiary treatment system shall be part of the EATP contractor to design and

execute.

3.11 Electrical Control

The operation of the treatment process shall be of semi-automatic. A completely assembled

and prewired control panel with mimic diagram consisting of weatherproof cabinet shall be

furnished. The control panel shall contain all metering and status indicators, motor starters,

program timbers, on-off-auto change-over switches and duty selectors for equipment.

Proper control sequence shall be designed according to system requirement and

manufacturer standards.

All sizing of electrical system shall be part of the EATP contractor to design and execute

3.12 Other Equipment

Any other necessary accessories, such as buffer, riser, scrum removal devices, partition,

control panel, collection devices, etc. for all the tanks and pumps (where necessary) shall be

provided in order to provide a fully working systems. All other necessary equipment which

fall under elecro-mechanical shall be part of the EATP contractor to design and execute

3.13 Valves

The Contractor shall supply and install all isolating valves and control valves as indicated

on the drawings and as required for the proper and efficient operation and maintenance of

the entire systems. All valves supplied shall be suitable for the working pressure and test

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pressure of the system as specified elsewhere in this specification. Regulating valves shall

be of similar materials as that specified for cast iron gate valves.

All regulating valves shall be lock shield type.

All valves shall be full line size.

Each valve shall have a purpose made reference number plate for label engraved or

stamped indicating the manufacturer’s catalogue number, pressure and temperature

ratings. Valves shall be arranged so that clockwise rotation of the spindle will close the

valve. Furnish all valves and accessory materials necessary in the piping whether or not

shown on drawings as flows. All valves shall be packed with an approved packing and

threads shall be coated with oil and graphite. Packings should be replaced when found

deteriorated on site. Where possible locate all valves at convenient positions of operation

from the floor with valve stems upright. Valves that are flanged shall have flanges to the

table specified for the pipework. Plastic or metal plates (rustless) shall be provided to

indicate the open / close status as well as the use of each valve in the pump and tank rooms.

All valves installation shall be part of the EATP contractor to design and execute

4 INSTALLATIONS

The Contractor shall check the associated civil work prior to the installation of any item of

machinery and carry out all necessary additions alterations as necessary at no extra cost.

The machinery shall be accurately installed to correct dimensions, alignments, levels, etc.,

all as indicated on the final drawings. The machinery shall be mounted on flat steel packing

pieces of thickness suitable to take up variations in level of the concrete foundations.

Suitable packing pieces shall be located adjacent to each holding down bolt and shall be

properly bedded by grinding the concrete surface to a smooth, level finish. The machinery

shall be aligned and leveled and the nuts of the holding down bolts tightened with a

spanner of normal length. The base plates shall be packed with grout after the machinery

has been run and checked by the Project Manager for stability and vibration. Installation

shall include the provision and fixing of all necessary holding down bolts, washers, nuts

etc. All equipment and materials of the same type shall be products of the same

manufacturer. All similar items of plant and their component part shall be completely

interchangeable. Spare parts shall be manufactured from materials similar to the originals

and shall fit all similar items of plant. Where machining may be needed before fitting

renewable parts, the machining fits with their tolerance shall be shown on the drawings

accompanying the instruction manuals. All motors and/or revolving parts shall be truly

balanced both statically and dynamically so that when running at normal speeds and any

load up to the maximum there shall be no significant vibration due to lack of balance. All

parts which can be worn or damaged by dust shall be totally enclosed in dust-proof

housings.

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5. MAINTENANCE FACILITIES

Permanent work platform and catwalk shall be the Contractor for access to elevated

equipment. The catwalk and platform for access shall allow a minimum width of 600mm.

Catwalk to maintenance platform shall be provided with railings and guards designed for

safe movement of personnel in a restricted space including provision for gaining access and

to accommodate maintenance personnel. Hand railing and guards shall be provided by the

Contractor for all concrete tanks to allow safe movement of personnel. Permanent I-beams,

lifting eyes, etc. shall be provided by the Contractor over major equipment which requires

lifting for overhaul and maintenance, if necessary. Waterproof power sockets required for

servicing shall be provided by the Contractor. The number and locations shall be proposed

by the Contractor and approved by the Project Manager / Engineer. Power supply to these

sockets shall be taken from control panel of the sewage treatment system. The design of all

permanent work platforms, hand rails, etc. shall be submitted to the Project Manager /

Engineer for approval. The loading and fixing method of lifting facilitate shall also be

submitted to the Project Manager / Engineer for approval and checking within 4 weeks on

award of Contract or receipt of letter of intent.

6. TESTING

The performance of the system shall be demonstrated by taking hourly samples of the raw

sewage and final effluent over a twelve hour period. The sample shall be taken at periods

approximately the flow rates specified by the plant. The sample shall be combined and a 5-

day BOD shall be run, the results of which must verify the capacity of the treatment plant

prior to acceptance.

7. TRAINING

Provided training facilities courses to ensure that the Project Engineer/their representative’s

staff associated with the project may acquire full knowledge and appreciation of all aspects

of the design, day-to-day operation, breakdown and routine maintenance, and fault

diagnosis of all plant, equipment and systems.

Training to the Project Engineer/their representative’s staff shall be held as appropriate at

the Contractor’s or manufacturer’s premises and on site. A detailed syllabus for each of the

training courses specified or proposed and the timing of the courses shall be submitted for

approval. The Contractor shall recommend the desirable qualifications and experience of

the trainees to optimally benefit from the courses. The plant operation training shall be

done for minimum period of 7 calendar days, at the time of commissioning and at the time

of handing over of plant. The Contractor shall be deemed to have included in his tender

price the cost of providing training facilities as specified.

In addition to the above, the Contractor shall submit to the Project Manager a list describing

such other spares and special tools, their number, price and where appropriate the

anticipated frequency of replacement as soon as possible along with minimum set of

mechanical, electrical spares and chemicals required.

CHUKA UNIVERSITY


SECTION-3: TESTING, COMMISSIONING AND HANDING OVER

1.0 GENERAL

The entire works included in this Contract shall be fully tested in stages as the work

proceeds and on completion of work as applicable. The plant testing will be primarily done

at manufacturing unit prior to dispatch and then on site. The Contractor shall provide

during normal working hours, all necessary labours, instruments, equipment, materials,

fuel, power and maker's representatives, to carry out such tests as may be necessary to

satisfy the Project Engineer so that the installation meets the requirement and intent of the

Specification as well as such tests required by Regulatory Authorities.

All tests shall be made in the presence of the Project Engineer/ their representative and/ or

any inspecting authority. At least seven working days’ notice in writing shall be given to

the inspecting parties before performing any test. Three copies of all test results shall be

submitted to the Engineer in A4 size sheet paper within two weeks after completion of the

tests. Tests described hereinafter and including all tests prescribed by the Authority having

jurisdiction shall be carried out. Any tests proved unsatisfactory shall be repeated to the

satisfaction of the inspecting parties.

The Contractor shall provide skilled technicians/engineer to commission the plant and

associated controls to the satisfaction of the Project Engineer/their representative. The

technicians/ engineers will be required to demonstrate the correct procedures in starting

and stopping the plant, running the various items of equipment under automatic and

manual control and the correct maintenance of the plant. Wastewater flow rates of all

equipment shall be adjusted to design conditions. Complete results of adjustments shall be

recorded and submitted.

2.0 ON-SITE TESTING AND COMMISSIONING

The Contractor shall start up, operate, test and adjust the systems in accordance with the

agreed programme. The setting shall be supervised by the manufacturer's representative,

who shall remain on site until the equipment is operating satisfactorily and accepted by

Project Engineer and/or their representative. The Contractor shall advice and co-ordinate

with the manufacturer's representatives so that all testing is carried out according to the

agreed programme.

The whole installation shall be given the tests to bring the systems into running order. The

Project Engineer/their representative shall be given reasonable notice together with a copy

of recorded test results, generally not less than seven (7) days, regarding the nature of tests,

the time and location. Acceptance tests will only be witnessed by the Project Engineer/their

representative when the submitted tests results are found satisfactorily. All instruments,

tools, material and labour required to perform these tests shall be provided by this

Contractor. Before the tests are carried out, the Contractor shall remove connected

equipment and components which are liable to damage under test, and shall provide and

fix all the necessary gauges, blanking flanges, etc.

CHUKA UNIVERSITY


Prior to the system start-up, the following inspection, tests and pre-commissioning

treatment shall be carried out by the Contractor:

A. Tanks and Level Switches

Check sides and edges of sectional tanks for distortion. The tanks shall be thoroughly

cleaned with water and drained before mains supply will feed in.

Also before mains supply will feed in, the level switch shall be simulated for the various

cut-in and cut-out settings.

B. Pressure Switches

The testing equipment arrangement for pressure switches and pressure gauges shall be as

shown on the drawings or of an approved equivalent. The pressure gauges to be tested

shall be connected as shown on the drawing in lieu of the pressure switch.

The gauges to be tested shall be regarded acceptable when the pressure readings of all three

gauges are the same throughout the jacking pressure range varied by applying the hand

pump.

C. Hydrostatic Tests

All parts of the water circuit shall be filled with water before hydrostatic pressure testing,

and pump running tests for verification of pressure and flow rate, are conducted.

The hand jacking pump shall be applied to increase the system pressure to 2 times the

working pressure or 1.5 times the working pressure plus 3.5 bar whichever is the lower but

in any case not less than 7 bars. The pressure shall be maintained for a period not less than

24 hours.

Where any section of pipework or equipment is found to be unable to withstand the

maximum pipework test pressure, it shall be isolated during the pipework test then that

section of pipework or equipment shall be made good and re-tested at the appropriate test

pressure.

The working pressure for various systems shall be as shown on the drawings.

Drains shall be hydrostatically tested to a water head of 1.2 m at the high end and not more

than 2.4 at the low end and shall show no appreciable loss of water after elapse of two

hours.

In every test, water used shall be left in the pipes until they are covered with earth or other

trench filling material to a depth of at least 1 m over the top of pipes and until permission is

given by the Project Engineer/their representative for the water to be released. If after the

Project Engineer/their representative has approved the sewer or pipeline and has given

CHUKA UNIVERSITY


permission for the trenches to be refilled the pipes become damaged and loses water from

any cause and/or admit subsoil water, the Contractor shall uncover the pipes and make

good the defect made good and the pipes retested as before and all at the Contractor's

expense.

D. Cleaning, Flushing and Pre-Treatment

Prior to start-up and hydraulic testing, the Contractor shall clean the entire installation

including all fitments and pipework and the like after installation and keep them in a new

condition. All pumping systems shall be flushed and drained at least once through to get

rid of contaminating materials.

All pipes shall be rodded to ensure clearance of debris, cleaning and flushing shall be

carried out in sections as the installation becomes completed. All strainers shall be

inspected and cleaned out or replaced.

When the entire systems are reasonably clean, a pre-treatment chemical shall be introduced

and circulated for at least 8 hours. Warning signs shall be provided at all outlets during pre-

treatment. The pre-treatment chemical shall:

Remove oil, grease and foreign residue from the pipework and fittings;

Pre-condition the metal surfaces to resist reaction with water or air;

Establish an initial protective film;

After pre-treatment, the system shall be drained and refilled with fresh water and

left until the system is put into operation.

Details and procedures of the pre-treatment shall be submitted to the Project

Engineer/their representative for approval.

E. Electrical Tests

Electrical insulation tests earth electrode resistance test and cost amenity test shall apply to

bus bars, isolators and other equipment and wiring where applicable. A 500V DC

instrument shall be used to check the insulation resistance.

The reading shall not be less than 1 mega-ohm in all instances. Function simulation tests

shall be performed to ensure that the systems have been installed to the control

requirements as described in the Specification therein.

F. Pump Drives

The direct coupling of the pump drives shall be dismantled before the pump motor control

panel is energized. The Contractor shall demonstrate to the Project Engineer/their

representative of acceptable clearances of the coupling alignment for ensuring satisfactory

power transmission. The coupling shall not be re-mated again till the correct motor rotation

has been demonstrated with power drawn from the energized pump motor control panel.

CHUKA UNIVERSITY


G. Pump Operating Test

The Contractor shall ensure to the satisfaction of the Project Engineer/their representative

that the installation or portion thereof which has been set to work complies with all

requirements including the following:

That the plant and apparatus shall be of robust construction and of capacity for the duty

specified.

That all valves, switches, controls and the like are properly regulated and capable of proper

operation and in the case of valves are capable of being shut-off.

That all apparatus shall be silent.

That all instruments are correctly calibrated and read accurately.

That all services are tested in accordance with the details of the relevant clauses of this

Specification.

3 STATUTORY AUTHORITIES' TESTS AND INSPECTIONS

As and when notified in writing or instructed by the Project Engineer/their representative,

the Contractor shall submit shop drawing and attend all tests and inspections carried out by

NEMA and other Statutory Authorities, and shall forthwith execute free of charge any

rectification work ordered by the Project Engineer/their representative as a result of such

tests and inspections where these indicate non-compliance with Statutory Regulations.

The Contractor shall be responsible for the submission of all necessary forms and shop

drawings to the Statutory Authorities which shall conform in layout to and kept by these

Authorities.

The submission shall comply with the requirements set forth in the current Codes of

Practice and circular letters of the Statutory Authorities. The shop drawings to be submitted

shall be forwarded to the Project Engineer/their representative/Structural consultant for

checking before submission. The Contractor shall allow for at least two submissions of

complete sets of shop drawings to the Authorities, one to be made within six months after

the award of the Contract but not less than six weeks before the inspection. The Project

Engineer/their representative may at his discretion instruct the Contractor for additional

submissions to the Regulatory Authorities whenever necessary.

The Contractor shall notify the Project Engineer at least seven days in advance of his

application for Regulatory Authority tests and inspections. On receipt of a confirmed date

for test and inspection the Contractor shall inform the Project Engineer/their representative

without delay.

CHUKA UNIVERSITY


4 COMMISSIONING

When the various installations have been completed and the preliminary commissioning

checks carried out, the Contractor shall set to work, regulate and calibrate all system in the

entire installation. Special attention shall be paid to the following items:

That all valves, switches, controls, etc. are regulated and capable of proper operation and in

the case of isolation valves that they are capable of tight shut off.

That all apparatus is silent in accordance with the requirements of this Specification.

That all instruments are correctly calibrated and read accurately.

That all services are tested in accordance with the details in the relevant clauses of this

Specification.

Operate pumps, pressure reducing sets, etc. to ensure that all control systems are

functioning correctly and are properly set, sequenced or interlocked.

5 FINAL ACCEPTANCE TESTS

Following commissioning and inspection of the entire installation, and prior to issue of the

Completion Certificate, the Contractor shall carry out final acceptance tests in accordance

with a programme to be agreed with the Project Engineer/their representative. Should the

results of the acceptance tests show that plant, systems and/or equipment fail to perform to

the efficiencies or other performance figures as given in this Specification, the Contractor

shall adjust, modify and if necessary replace the equipment without further payment in

order that the required performance is obtained. Where acceptance tests are required by

the relevant Authorities having jurisdiction, these tests shall be carried out by the

Contractor prior to the issue of Completion Certificate to the acceptance of the Authorities.

Contractor will extend all technical help and do liasoning on behalf of Project Engineer to

obtain necessary permit to operate / Consent to operate from authorities. The fees required

will be paid by Project Engineer/ their representative directly. Though payments are made

by Project Engineer, it will be entire responsibility of contractor’s to obtain Consent to

Operate from respective authorities.

6 REJECTION OF PLANT

Any item of plant or system or component which fails to comply with the requirements of

this Specification in any respect whatsoever at any stage of manufacture, test, erection or on

completion at site may be rejected by the Project Engineer/their representative either in

whole or in part as he considers necessary/appropriate.

Adjustment and/or modification work as required by the Project Engineer/their

representative so as to comply with the Authority's requirements and the intent of the

Specification shall be carried out by the Contractor at his own expense and to the

satisfaction of the Authority/Project Engineer/their representative.

CHUKA UNIVERSITY


After works have been accepted, the Contractor may be required to carry out assist in

carrying out additional performance tests as reasonably required by the Project

Engineer/their representative/Project Engineer.

7 WARRANTY AND HANDOVER/ DEFECTS LIABILITY PERIOD

The Contractor shall warrant that all plant, materials and equipment supplied and all

workmanship performed by him to be free from defects of whatsoever nature before

handover to the Project Engineer/their representative. The designed performance of plant

shall be monitored for minimum period of 3 months. The defects liability period of 12

calendar months will commence from the date of receipt of approval from concerned

authorities. The contractor shall handover all guarantees/ warrantees of all equipments

used in the plant and or transfer all such warrantees/guarantees on the name of Project

Engineer.

It will be obligatory on part of contractor to extend all exhausted guarantee/warrantee for

further period of minimum 3 years, from date of obtaining authority approval in writing, at

no extra cost to project Engineer.

Defects liability period will be considered as completed satisfactory, only after getting plant

performance within prescribed design limits, for minimum plant up time of 85% of 1

calendar year for entire operations during defects liability period.

Any deficiency noted during defects liability period or part thereof, will automatically

extend the defects liability period equal to duration for which plant performance was not

met with, at no extra cost payable to contractor on any account.

8. HANDING OVER OF DOCUMENTS

All testing and commissioning shall be done by the Contractor to the entire satisfaction of

the Project Manager and all testing and commissioning documents shall be handed over to

the Project Engineer/their representative. The Contractor shall also hand over all

maintenance and operation manuals, all certificates and all other documentation as per the

terms of the contract to the Project Engineer/their representative.

9. OPERATION AND MAINTENANCE OF PLANT

The cost of operations and maintenance including mechanical, electrical spares, chemicals

required etc as and when required along with necessary manpower on 24 hours basis,

during the defects liability period of 1 calendar year or any extension thereof, shall be

included in the cost and no extra cost will be payable to contractor on any account thereof.

Contractor shall indicate plant operation and maintenance cost along with routine

mechanical, electrical spares and chemicals including round the clock manpower for plant

operation for period of 3 years, to be counted from date of satisfactory completion of defects

CHUKA UNIVERSITY


liability period. The Project Engineer will enter in to plant operation maintenance contract

on successful completion of defects liability period at the rates quoted now.

The maintenance amount so quoted and approved will be payable every half yearly in

advance at the beginning of half year period on receiving necessary supporting invoice

from contractor. Contractor shall provide list of optimal spares for the pant, that to be kept

for entire period for plant maintenance, which will be maintained by him as optimal

inventory at plant site at no extra cost to Project Engineer.

CHUKA UNIVERSITY


DESIGN CALCULATIONS for Chuka University Extended Aeration Process

Capacity: Average Flow 0.285 MLD

S No Description of Parameter Value Unit Requirement

Quantity of Sewage Generated 285,000.00 Lpd

0.29 MLD

285.00 Cum/day

Raw Sewage Characteristics

1 Average Sewage flow entering the treatment plant 285,000.00 lpd

Assumed Peak Factor 3.00

2 Peak Sewage flow entering the treatment plant 855,000.00 lpd

3 COD 400 - 800 mg/Lt

4 BOD 300.00 mg/Lt

5 TDS 1520-1620 mg/Lt

6 TSS 460.00 mg/Lt

7 pH 6.50

1 Inlet Chamber

Quantity of Flow (Ave) 285.00 Cum/day

Peak Flow 855.00 Cum/day

0.01 Cum/Sec

Assumed Detention period 10.00 sec

Volume of the Inlet Chamber 0.10 Cum

Assumed Depth of flow 0.30 m

Area Required for Inlet Chamber 0.33 Sq.m

Assumed Length to Breadth Ratio 1.00

Breadth of the Tank 0.60 m

length of the Tank 0.60 m

2 Screen Chamber (Fine Screens)

Peak Design Flow 0.01 Cum/s Assume Size of the screen flats of size having a

thickness of 10 mm and a width of 50 mm (CPHEEO

page no 201)

Assume Clear spacing between bars, o 6.00 mm 20-50mm, pg.201 of CPHEEO Manual

Velocity ahead of screen (Va) 0.60 m/sec pg. 202 of CPHEEO Manual

Area of Screen Channel, A= (Q/Va) 0.02 m2

Keeping Side Water Depth 0.60 m

Width of each screen channel, W 0.30 m

Water depth upstream, ha = A/W 0.07 m

t 0.01 m

Number of openings in chamber, W = X.o + (X - 1).t where , X

= No. of Opening ; o = Clear Space between bars ; t =

Thickness of flat

19.00 no

Total width of opening, Ws =x*o 0.11 m

Assume Angle of inclination 45.00 Degree

Assumed Detention Period in the Screen channel 3.00 sec

Assume Length of the screen chamber 1.80 m

Inclined height of the screen, H1 0.09 m

say

Velocity through the screen, Vs= Q/H1*Ws 0.92 m/sec

Head loss thru screen in normal condition, h1=0.0729(Vs2-Va2) 0.04 m less than 0.15 m hence ok

Head loss on 50% clogging h1=0.0729(2*Vs2-Va2) 0.10 m less than 0.3 m hence ok

Water Depth downstream Hb, (Za-Zb)+Va2/2g-Vs2/2g+Ha-

Headloss thru screen in normal condition

0.00 m

Water Depth downstream Hb, (Za-Zb)+Va2/2g-Vs2/2g+Ha-

Headloss thru screen in clogged condition

-0.06 m

3 Equalization Tank (Collection Chamber )

Peak Design Flow 855.00 Cum/day

Assumed Detention period 2.1 hours

Volume of the Tank 74.8125 Cum

Assumed Depth of Liquid column 2.5 m

Area required for the equalization tank 29.925 Sq.m

No. of Tanks Proposed 2

area required for each equalization tank 14.9625 Sq.m

Length to Breadth ratio 1

Breadth of the tank 4 m

Length of the tank 4 m

Provide 2 No. Equalization tanks each measuring 4.05m by 3.95m by 3.4m high SWD + 0.3M Freeboard

Design of Sewage Treatment Plant

Guidance:Yellow cells are input information to be suitably filled. Green cells are to be reviewed and modified/updated.

Provide the Dimension of Inlet Chamber as 0.6 m x 0.6 m x 0.3 m SWD + 0.3 m Freeboard

Provide the Dimension of Screen Chamber (Fine Screens) as 1.8 m x 0.3 m x 0.6 m SWD + 0.3 m Freeboard

CHUKA UNIVERSITY


Mixing Arrangements

Assumed BOD reduction in the tank 15% Percent

Incoming BOD of Raw sewage 300.00 mg/L

BOD to be reduced 45 mg/L

BOD Load 38.5 kg/day

Oxygen required to remove BOD load 2 kg/kg of BOD

Oxygen required 77.0 kg/day

3.21 kg/hr

Actual Air Required 201.96 Cum/hr

Provide Corse bubble aeration grids for 210.00 cum/hr

4 Raw Sewage Pumps

No. of pumps - (1W+1SB)

Type of Pumps - Submersible/Horizontal Centrifugal

Average flow 285.00 Cum/day

Number of working hours 20 hrs

Flow Capacity of Pump required 14.25 Cum/hr

Proposed pumps 2 numbers (1W + 1SB), flow per Pump14.25 Cum/hr

3.96 lps

Head required 5.00 m

HP required for pump 1.00 hp

5 Aeration tank

No of Tanks 1

Flow - completely mixed

Q- per tank 285.00 cum/day

BOD 255.00 mg/Lt

MLSS 2500.00

Type Aeration - Diffuser type fine bubble

Blowers - 1.00 ( 1W+1SB)

F/M assumed 0.12

Volume of the tank 242.25 Cum volume of tank as per 13.6 page 226

Add additional volume of 25% for sludge recycle 60.56 Cum

Total volume of tank 302.81 Cum

Hydraulic Detention Time 0.02 day

Depth of the tank 3.40 m

Area of the Tank 89.06 Sq.m

Area for each tank 89.06 Sq.m

Assumed Breadth to Length Ratio 1.00

width of the tank 9.5 m

Length of tank 9.4 m

6 Blower capacity

BoD load 72.68 kg/day

3.63 kg/hr

Oxygen Required for 1 kg BOD removal 2.00 kg

Theoretical Oxygen 7.27 kg/hr

Actual requirement of air 343.32 cum/hr

Total Air Requirement 545.50 Cum/hr

fine bubble diffuser assumed to inject oxygen of 5.00 cum/hr

Provide Membrance diffuser for aeration tank 109 No.

Provide 2 Blowers of capacity of 10 Horse power (1W+ 1

SB) 545.50cum/hr

for each tank

Sludge Volume Index assumed 100.00 Page 235-SVI 80 to 150

Sludge Recirculation Qr/Q=Xt/((10 6̂/SVI)-Xt) 0.33 table 13.1 page 235 or taking SVI 100

Volumetric loading rate 0.24 kg/cum

Xt V = 605625.00

ay Q (Yo – Ye) qc/(1 + ke qc) 66975.00 equation 13.7 page 227

0.11

0.05

Hydraulic Mean Cell Residence Time 19.77 days

Assumed Reduction in the Aeration Tank 95.00 %

Outlet BOD from the Aeration tank 12.75 mg/L

Provide 2 Blowers of capacity of 10 Horse power (1W+ 1 SB)

Provide 2 No. (1 working & 1 stand by), 33 URAI( 210m3/hr; 5 Horse power) Blowers

Provide 2 No. (1 working & 1 stand by), 1.0 Horse Power sludge pump

Provide 5 No. Aeration tanks each measuring 1.92m by 3.95m by 3.4m high SWD + 0.3M Freeboard and 5 No. Aeration tanks each measuring

1.92m by 3.75m by 3.4m high SWD + 0.3M Freeboard

CHUKA UNIVERSITY


7 Secondary clarifier

No. of Tanks 1

Average Flow in each tank 285.00 cum/day

SOR 25.00 Cum/Sqm/day

Table 12.1, but it is 8-15 for average flow and 25-35 for

peak flow for extended aeration

SWD 2.00 m

table 12.1, it is 3.5-4.5 m for extended aeration,

although para 12.4.2.5 give depth 2 m in vertical flow

tanks

Solid conc. In settled sludge -% 0.8 to 0.9 %

Withdrawal frequency - continuous

Area Required for the Tank 11.40 Sq.m

Length Required for Secondary Settling Tank 2.39 m

Assumed Detention Period 2.00 hrs 1.5-2 hrs as per table 12.1

23.75 Cum

Depth of the Clarifier assumed 2.00 m

Area of the Clarifier 11.88 Sq.m

Surface Loading Rate 24.00 Cum/Sq.m/day

Assumed BOD reduction in Clarifier 10.00 %

Outlet BOD from Clarifier 11.48 mg/L

8 Return Activated Sludge /Excess sludge pumps

Type of Pumps - Centrifugal

No. of pumps 1 (1W+1SB)

Assumed return flow 50.00 %

Return sludge Pumps 142.50 Cum/day

Operating hours 20.00

Capacity of pump required 7.13 Cum/hr

1.98 lps

Head required 5.00 m

Power requirement for the Pump 0.50 Hp

9 Treated Sewage Sump/Chlorination Chamber

Assumed Detention time 30.00 Minutes

Average Flow 285.00 Cum/day

Volume of the tank 5.94 Cum

Provide a depth of tank as 1.95 m

Length to breadth ratio 2.00

Area of the Tank 3.04 Sq.m

Rectangular length of the tank Size 3.50 m

Provide 2 No. (1 working & 1 stand by) 0.5 Horse power, Qmax of 7.13m 3/hr and maximum head of 5.0m Sludge return pump

Provide the Dimension of Treated Sewage Sump/Chlorination Chamber as 1.6 m x 3.1 m x 1.95 m SWD + 0.3 m Freeboard

Provide 2 No. secondary Clarifier each measuring 1.92m by 3.95m by 3.4m high SWD + 0.3M Freeboard and 2 No. secondary Clarifier each

measuring 1.92m by 3.75m by 3.4m high SWD + 0.3M Freeboard