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2ND ANNUAL DAM REHABILITATION & MANAGEMENT CONFERENCE THE ROLE OF MUNICIPALITIES CASE STUDY: MTHATHA DAM, ORTAMBO DISTRICT MUNICIPALITY,EC 24- 25 TH JULY 2012 PRESENTED BY JB NARTEY, 073-7369034

5.J.B Nartey

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Page 1: 5.J.B Nartey

2ND ANNUAL DAM REHABILITATION & MANAGEMENT CONFERENCE

THE ROLE OF MUNICIPALITIES

CASE STUDY: MTHATHA DAM, ORTAMBO DISTRICT MUNICIPALITY,EC

24- 25TH JULY 2012

PRESENTED BY

JB NARTEY, 073-7369034

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OVERVIEW

BRIEF DESCRIPTION OF THE MTHATHA DAM AND THE MTHATHA RIVER

ROLE IDENTIFICATION

DAM REHABILITATION & MANAGEMENT PROCESS

CONCLUSIONS

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MTHATHA DAM Ownership: Owned, operated and maintained by DWA according to the National Water Act. 36 of 1998

Opening date; 1977

Type: It is an earth embankment dam

Purpose: Multipurpose-

Potable water Supply-It serves as the main source of raw water supply (65.9 ML /day)for the Thornhil WTW which treats and supplies water to the city of Mthatha and its environs with a total population of about 750,000.

Hydropower generation- Supplies water for hydropower power generation by Eskom at 2 No. 6 MW hydropower station s located downstream of the Mthatha river ( First/Second Falls hydro scheme ) -338 ML/day is utilized, but since the water is returned to the river, this use is non-consumptive

Recreation/Fisheries- Fishing competitions held bi-annually by the Dept.of Agriculture. However these activities are currently defunct.

Location; The Mthatha Dam impounds the Mthatha river at a location about eight kilometers upstream of the city of Mthatha in the OR Tambo District Municipality of the Eastern Cape

Accessibility: located off the R61 by a 2km partially tarred access road currently undergoing rehabilitation.

Coordinates; 31°32′56″S , 28°44′0″E / 31.54889°S, 28.733333°E

Height; 12- 38 meters

Crest Length;680 meters

Storage Capacity; 253,674,000 cubic meters

Surface area; 2,542 hectares (6,280 acres)

Raw Water Quality: The upper reaches of the river/Headwaters where the dam is located are almost pristine so negative impacts on water quality are relatively low. However forestry activities upstream may be releasing herbicides and pesticides and poor quality effluent in this section but their impact is currently not detectable in the available water quality data.

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MTHATHA DAM-AERIAL VIEW

MTHATHA DAM

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MTHATHA DAM-DAM WALL, SPILLWAY/OUTLET WORKS

spillway/

outletDam

wall

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MTHATHA DAM -DOWNSTREAM SLOPES

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MTHATHA DAM-UPSTREAM SLOPES

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MTHATHA DAM-ACCESS BRIDGE/CONTROL TOWER/SPILLWAY

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MTHATHA DAM-SPILLWAY/OUTLET

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MTHATHA RIVER-CATCHMENT CHARACTERISTICS

Source: The Mthatha river drains from the Baziya mountain range at Langeni Forests -1500m above sea level.

Mouth: Indian Ocean at an estuary at Coffee Bay,

Catchment Size : 2600km2

Major Tributaries; Ngqungqu and Cicira

River Flow: From the North West to the South East

Length: 250 km

Climate: The area experiences a temperate to subtropical climate, with rainfall occurring predominantly in summer. Average rainfall is relatively high along the coast (1 000 to 1 300 mm per annum), decreasing towards the interior (700 mm per annum) and finally increasing in the upper catchment areas of the escarpment (up to 1 500 mm per annum).

Geology: Dominated by mudstone, shale and considerable amount of dolerite

Vegetation: vegetation cover consists of temperate and transitional forests. The headwaters are under pine plantations.

Land use:

Grazing for livestock occupies 70%, Settlements and subsistence agriculture takes up 15%., Approximately 4% is under commercial afforestation, e.g. Langeni plantations and Only 0.05% is under irrigation.

Water Use:

Commercial Forestry-related industries,( e.g. the sawmills at Langeni and KwaBhaca ),Urban settlements and small scale industrial water users, rural water users, small scale Irrigation for subsistence agriculture. Etc.

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MTHATHA RIVER-ECOLOGICAL HEALTH

Upper Reaches The upper reaches of the river is almost pristine so negative impacts on water quality are

relatively low. However forestry activities upstream may be releasing herbicides and pesticides and poor quality effluent in this section but their impact is currently not detectable in the available water quality data.

Middle Reaches Dense peri-urban and rural settlements has impacted negatively on this section of the river. Some disturbed areas due to human activities have been invaded by alien vegetation, resulting in

undercutting and slumping of the riverbanks, siltation and reduced run-off . Overloaded sewage treatment works( operating capacity=18 ML/day, design capacity=12

ML/day), poor management of the sewage systems result in the discharge of untreated sewage effluent into the river,(Green drop status-22%)

Lower Reaches Dense peri-urban and rural settlements has impacted negatively on this section of the river as

well. High pollution levels further downstream of the dam due to the disposal of raw or poorly treated

domestic and industrial waste(liquid/solid) into the river and secondly high erosion in certain areas of the catchment caused by poor land use practices.

High nutrient loads causing eutrophication and proliferation of potential toxic algal blooms Increased sediment load due to erosion from overgrazing, poor agricultural practices and

vegetation clearing within the catchment.

(Source: EC River Health Program; Technical Report: Mthatha River Monitoring 2004-2006)

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MTHATHA RIVER- UPPER CATCHMENT- FORESTRY AND TIMBER RELATED ACTIVITIES -

LANGENI SAWMILLS

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MTHATHA RIVER –UPPER CATCHMENT-UPSTREAM OF THE LANGENI

SAWMILLS:

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MTHATHA RIVERMIDDLE CATCHMENT- REFUSE DUMPED ON THE BANKS OF THE

MTHATHA RIVER AND INFESTATION OF THE ALIEN INVASIVE: BUGWEED

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MTHATHA RIVER

MIDDLE CATCHMENT-SAND MINING ON THE RIVER BANK TO MAKE BRICKS. THE BRICK MAKING ALSO MAKES USE OF THE RIVER WATER, WHICH

EXPOSES THE BRICK-MAKERS TO HARMFUL SUBSTANCES AND DISEASE.

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MTHATHA RIVER-LOWER CATCHMENT-ALIEN VEGETATION AND HIGH SEDIMENT

LOAD

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DAM REHABILITATION & MANAGEMENTROLE IDENTIFICATION

PRIMARY ROLE The National Water Act ( Act No.36 of 1998) assigns the responsibility for the rehabilitation and management of most major dams in

the district to the Department of Water Affairs(DWA). However there are other smaller dams and dug outs which are owned, operated and maintained directly by local municipalities, local

farmers and game parks within the district. SECONDARY ROLE The National Water Act(Act No.36 of 1998 ) assigns the role of a Water Service Authority/Provider to the OR TAMBO

District Municipality and is responsible for the treatment, storage and supply of potable drinking water to the city of Mthatha, the district administrative capital and surrounding towns.

This therefore implies that OR Tambo DM is highly dependent on regular raw water supplies from the Mthatha dam in order to carry out this legislative function of a water service authority/provider.

OTHER ROLE PLAYERS /STAKEHOLDERS DEAT- Dept of Environment afffairs and Tourism Beneficiary Communities(Traditional Councils) Department of rural development and Land reforms-custodians of rural or communal lands Department of Agriculture, forestry and fisheries ESKOM Water User Associations Water Boards Department Of Human Settlements Surrounding Local Municipalities- Nyandeni, Mthlotlo and KSD Local Municipalities

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DAM ASSET MANAGEMENT PROCESS Dam Asset Management Planning

Dam Operation Dam Maintenance and Rehabilitation

Dam Safety

Water Resource Management Raw water Quality management Raw water utilization management Raw Water Conservation and demand management Environmental Conservation Catchment land use management

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DAM ASSET MANAGEMENT PLANNING

Dam asset strategic planning process

• IDP: conceptual district wide water master plans/WSDP. Ward based planning & Information System

(Municipal Systems Act 32 of 2000)

•Dam Asset Mgt Policy• Dam O & M Plan• Dam Emergency preparedness plan

• WCDM master plans • Disaster & Risk Management plan(Disaster Mgt Act 2002)wddd

•Development plans• Conversion of borehole fed standalone schemes into Mthatha river fed Regional Water Supply Schemes•Upgrading of existing town sanitation systems into full water borne sewerage system.•Housing Developments(Emergency housing,eradication of informal settlements, urban renewal programs)

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DAM OPERATION

Dam Operations Plant operators: WTW

•Example: In times of extreme staff shortage at the Mthatha dam site the municipality sometimes deploys on a part-time basis some of its plant operators from the water treatment works to assist in the normal operations of the dam(outlet works) and also for skills transfer.

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DAM MAINTENANCE & REHABILITATION

DamMaintenance & Rehabilitation

programs

• Labor Intensive construction technology, Local SMEs, Ward Committees, Community Dev’t

Workers(CDW) etc• Public Participation policy &

strategy(Municipal Systems Act 32 of

2000)

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•The use of Labor Intensive methods are applied in the rehabilitation of the access road to enhance the contribution of local labor and help to reduce the unemployment rate which currently stands at 68.1% within the district.•Local SMEs and unskilled local labor are attached to the appointed service provider for skills transfer/mentorship purposes.

DAM MAINTENANCE & REHABILITATIONExample -Dam access road rehabilitation(2km)

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DAM SAFETY

Dam Safety Inspections/Audit are conducted periodically by the DWA dam safety office.

Plans are underway for the implementation of the following dam safety programs:

Dam reservoir augmentation –raising of the dam wall to meet the growing water demand requirements

Rehabilitation of the outlet works to increase capacity and method of delivery. etc

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WATER RESOURCE MANAGEMENT-RAW WATER QUALITY MANAGEMENT

Raw water quality results obtained from the Mthatha dam had been fairly stable throughout the years.

Raw Water Quality Management

Raw Water Quality Trends/Raw water user quality

requirements: Ward Committees, Water User

Associations, Village water committees

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WATER RESOURCE MANAGEMENT -RAW WATER UTILISATION MANAGEMENT

Raw Water Utilization policy

dev’t & implementation

Raw water utiliz

ation

trends/re

quirements; W

ard

committees, W

ater User

Associations,Villa

ge water

committees

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WATER RESOURCE MANAGEMENT - WATER CONSERVATION & DEMAND MANAGEMENT.

WCDM

• Water services by-laws,

• Water tariff policy,• Credit Control/Debit

collection policy •Water Use restrictions

WCDM master plan and

implementation(Water Services Act(Act 108 of

1997);

• Awareness

campaigns,

comm. &

educational

programs,

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WATER RESOURCE MANAGEMENT -ENVIRONMENTAL CONSERVATION

Ecological Restoration programs:

Working for Water programs

Implementing agents;CDWs

Water Pollution Control

• Public Participation policy & strategy

(Municipal Systems Act 32 of 2000)

• Participate in public awareness, comm. & education programs;

Water week

River Ecological Studies/Surveys

Ward Committees, Community

Dev’t Workers

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WATER RESOURCE MANAGEMENT -EXAMPLE-WORKING FOR WATER PROGRAM- MTHATHA RIVER CLEANING

Clearing of invading alien plants and removal of solid waste in and around the river using labor intensive/manual methods so as to conserve the ecological functioning and biological diversity of the Mthatha river.

OR Tambo DM entered in to a memorandum of agreement(MOA) with DWA for the planning, procurement of service providers/suppliers and implementation of the exercise.

Duration= Aug.2010 to 25th March 2012 Excellent low cost activity Project Budget-R9.8 million Budget Source-DWA Job opportunities created -217 Direct Involvement of the local communities which has led to the socio-

economic upliftment of the communities through job creation.

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WATER RESOURCE MANAGEMENT ACTIVITIES ENVIRONMENTAL CONSERVATION

EXAMPLE-WORKING FOR WATER PROGRAM- MTHATHA RIVER CLEANING

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WATER RESOURCE MANAGEMENT ENVIRONMENTAL CONSERVATION

Environmental Conservation

• District spatial planning &

environmental mgt technical

forum, • Public

Participation policy & strategy

• (Municipal Systems Act 32

of 2000)

• EMP, • Environmental policy statement,

• IWMP (NEMA Act 1998,NEMWA 2008)

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WATER RESOURCE MANAGEMENT -CATCHMENT LAND USE MANAGEMENT

The Spatial Development framework provides guidance to the spatial distribution of current & future desirable land uses/activities within the district municipality in order to give physical effect to the vision, goals and objectives of the IDP.

Catchment Land Use Mgt

Environmental & spatial planning

forum

Spatial Dev’t framework/Land Use

Mgt Guidelines.Ward Based planning & Information System

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CONCLUSION The National Water Act No.36 of 1998 assigns the primary

role of the rehabilitation and management of the Mthatha dam to the DWA. However as a major stakeholder/role player our role is therefore to offer the much needed collaboration, assistance, support, facilitation and advise to the work of DWA in the rehabilitation and management of the Mthatha dam. This is to ensure the sustainability of the raw water supply for continuous economic productivity, promotion of human health ,survival of our natural ecosystems and the support of the tourism/recreational industries.

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REFERENCES

OR TAMBO DM IDP -2012/13

OR TAMBO DM-WATER MASTER PLANS-2011/12

NATIONAL WATER ACT,1998

NATIONAL WATER POLICY,1997

DWA WEBSITE(www.dwa.gov.za)

THE WATER SERVICES INFRASTRUCTURE ASSET MANAGEMENT STRATEGY_2010

NATIONAL WATER RESOURCE STRATEGY(NWRS,2004)

EC RIVER HEALTH PROGRAM; TECHNICAL REPORT: MTHATHA RIVER MONITORING 2004-2006

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THANK YOU