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December 14, 2017 Infrastructure WATER, WASTE WATER AND STORM WATER

Infrastructure - Andhra Pradesh · Phasing of Infrastructure in line with Organic Growth of City ... (WMD) concept. Total length of pipes of varying ... DI-K9 pipes for diameter of

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Page 1: Infrastructure - Andhra Pradesh · Phasing of Infrastructure in line with Organic Growth of City ... (WMD) concept. Total length of pipes of varying ... DI-K9 pipes for diameter of

December 14, 2017

Infrastructure

WATER, WASTE WATER AND STORM WATER

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Infrastructure Vision – Water, Wastewater and Storm water Panel Discussions Challenges Possible solutions Phasing of Infrastructure in line with Organic Growth of City

Advance infrastructure or match investments to suit realistic growth of city

Resilient and sustainable Infrastructure in relation to Quality and Quantity

Provide adequate standby arrangements with improved level of service

Emerging Trends in Advanced Treatment Technologies

Treatment technologies for Water and wastewater, ZLD (Zero Liquid discharge) concepts

Public participation for Water Canal and review of SWD and Flood Flow canal concepts and possibility of introducing ABC concepts.

Friendly public spaces, bring people closer to water like ABC concepts in Singapore

Background note on infrastructure components of Water, Wastewater and Stormwater 1.0 Water Infrastructure for Amaravati City Government of Andhra Pradesh has embarked on development of new Capital City of Andhra Pradesh which is being located between the cities of Vijayawada and Guntur. The new capital of Andhra Pradesh is christened as Amaravati and is envisioned to be the pioneer Smart City of India with world class infrastructure standards and guidelines. Amaravati, the new Capital City of Andhra Pradesh is envisaged to be of world-class standards with a vision of increasing its prominence in the world. In pursuance of developing the capital city region, ADC & APCRDA has taken up preparation of Integrated Master Plan and Detailed Project Reports for Phase – I infrastructure works encompassing the Capital City of an area of 217 sq. km. The smart infrastructure master plan consists of individual master plan elements, such as, Transportation, Water Supply, Waste Water Disposal, Storm Water Management, Municipal Solid Waste Management, Electricity, City Gas, District Cooling, ICT Infrastructure, Safety & Security, Disaster Management, seamlessly integrated, supported by command and control structure for each of them. The Vision of the proposed water supply system for Amaravati capital city is to provide safe and reliable water supply to all the stakeholders ensuring continuous 24 x 7 water supply, maintain best potable water quality standards and benchmarking the design, operation and maintenance to international best practices. Water supply system is planned for the Amaravati capital city to cater for 38,83,120 inhabitants meeting the water demand of 931MLD for the Design Horizon 2050. The population is arrived by Land use Plan and Floor Space Index (FSI) method. Krishna River is considered as the source of water supply for the city as it is nearby with Existing Prakasham Barrage and proposed Vaikuntam barrage on the downstream and upstream of Krishna River. Two source locations of water supply are identified. For Phase-I of the project, 383 MLD of water will be drawn from the Prakasam barrage to meet the projected water demand by 2030. For the Phase-II of the project, proposed Vaikuntapuram barrage on Krishna River will provide balance 548 MLD to meet the projected water demand by 2050.

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A continuous water supply system is proposed from Source to consumers in 2 two different stages. In the first leg, raw water will be lifted from the river and pumped to the two Water Treatment Plants (WTP), 1 km and 5 km from the source points. In the 2nd leg, treated water will be pumped directly to the consumer premises from the clear water reservoir at WTP. Direct pumping will ensure a residual pressure of 17 m at ferule point in consumer premises. The treated water from WTP will be pumped through 4.4 km long clear water transmission main to a 45 km long ‘Ring Main’, from which, water will be drawn from 24 ‘Tapping Points’ to 60 ‘Water Distribution Districts’. The concept of Ring main is new to this scheme. Water supply infrastructure in Phase-I consists of Intake Well-cum-Raw Water Pumping Station, Raw & Clear Water Transmission Mains, Water Treatment Plant, Clear Water Reservoir, Clear Water Pumping Station, pipeline network in Water Distribution Districts, Water Supply SCADA, Fire Services Hydrants. Intake at river bank consists of twin RCC Jack Wells inside the river through which water will be lifted by Vertical Turbine Pumps (4 working + 2 standby) with Sluice gates operating at various levels to tap the water during various seasons of the year. Raw water and clear water transmission mains are 1900 mm and 2400 mm MS pipes respectively. Transmission mains are designed for economic size, structural design and surge analysis using Pipe-2016: Surge software developed at University of Kentucky, USA. Surge protection devices consist of Bladder Vessels and combinational Air valves at appropriate locations of the outlet of the raw and clear water pumping stations. Pipeline network in the distribution system is designed using ‘Water GEM’ software and applying Water Management Districts (WMD) concept. Total length of pipes of varying sizes from 300 mm to 2400 mm in the transmission main segment feeding up to the water distribution centers is 113.40 km. Pipe material consists of MS pipes for diameter above 1000 mm and DI-K9 pipes for diameter of 300mm to 1000 mm in the transmission mains and DI-K7 pipes in the distribution network. Water Treatment Plant at Undavalli is planned for 380 MLD capacity with modular concept of 190 MLD capacity for immediate implementation and another 190 MLD addition at a later stage. Suitable technology shall be adopted to treat the raw water to achieve the best treated water standards. Complete Automation of the system is adopted for the WTP. Clear Water Reservoir (CWR) after the treatment from WTP will be stored in CWR designed for 2 compartments with 4 hours each. Besides serving as chlorine contact tanks, CWR will act as master balancing reservoir to deliver water by direct pumping to the water distribution districts / consumer premises. Clear Water Pumping Station will accommodate 21 Horizontal split-casing centrifugal pumps (10W+5S, 2W+1S, 2W+1S), inlet and outlet manifolds, service bay and control panels to operate the pumps. Water Distribution Districts (60 No.) are equipped with flow control devices to regulate flow for equitable water distribution to the consumers. It comprises cushion tanks (51 No.), ground level service

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reservoirs (8 No.) with pump house, Reservoir Management System(RMS), Tapping Control Management System (TCMS) and Bypass Management System(BMS). Electro-mechanical Works consist of pumps, motors, transformers, electric sub-stations, electric supply from nearby service feeder, DG set, electromagnetic flow meters, etc. In raw water pumping station 6 vertical turbine pumps (4W+2S), in clear water pumping station 21 horizontal split-casing centrifugal pumps (14W+7S) and in GLSRs 24 horizontal splitcasing centrifugal pumps (16W+8S) of varying capacities are provided. Pumps are provided with Variable Frequency Drive (VFD) to control both the speed and torque of a standard induction AC electric motor. Water Supply SCADA system allows an operator to monitor and control the water supply system at every stage of its operation. This system allows remote sites to communicate with a control facility and provides the necessary data to control processes. It provides an economic advantage on the maintenance of the system. SCADA identifies the faults or defects in the system over a large foot print area and helps to diagnose and repair the system from the control center. In water supply SCADA 3 major elements: Master Terminal Unit, Remote Terminal Unit and communication equipment are provided for online monitoring, command and control, reporting and documentation services. A schematic diagram of water supply SCADA operation is outlined. Fire Fighting Services: Water demand for fire services for the capital city is arrived as 4.13 MLD and 6.19 MLD by the year 2035 and 2050 respectively. Provision is made in the water supply system to draw water for firefighting, in case a fire breaks out in any neighbourhood of the city. Fire hydrants are proposed to be installed in the pipe lines in LPSlayout area at 150 m apart. A total of 2000 fire hydrants are provided in the system WATER SUPPLY DEMAND Design Period In this project, design periods for water supply are adopted for the following horizon years: Base year : 2020 Intermediate year : 2035 Ultimate year : 2050 Considering base year as 2020, water from River Krishna will be drawn on the upstream of Prakasam Barrage for the first 10 years (i.e. upto 2030) and the balance water drawl will be from proposed Vaikuntapuram barrage for the next 20 years (i.e. from 2030 to 2050) Projected Population The Amaravati Capital city is envisaged to be positioned as the key economic and administrative hub in the new Andhra Pradesh State. For the region to sustain the anticipated economic activity, it is important to set aside available adequate land for setting up industries and corporates, undertake

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development of basic infrastructure and impart necessary training and skill development for its people to be industry ready. The total population numbers for Capital City are as below:

Sr No

Service Category Population 2050

1 Residential 3,833,120 2 Commercial 610,638 3 Institutional 570,951 4 Industrial Work Force 88,487 Total 5,103,196

Per Capita Demand: Per capital consumption defines the rate of water consumed by each person in a specified community depending on all his activities related to usage of water in a day.

The water supply demand for the city is assessed based on the projected population over the years and per capita rate of water supply established for different land uses and utility services, using CPHEEO standards, technical expert committee and comparative studies made on International best practices coming up with 10% demand for each service category to suffice floating population and infrastructure cushion, 10% loss for ‘Unaccounted for Water’, 2% for transmission losses, 3% for losses at WTP and Firefighting demand with 100*sqrt(P), where ‘P’ is population in thousands. The total water demands for residential and workforce population for Commercial/ institutional/Industrial (I3 category) and additional demands as stated above thus arrived is given below.

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Design Population The present DPR is prepared based on FAR based population projections as it provides realistic estimation of the population based on Land use pattern and Floor Area Ratio of the Master Plan area. Thus, the projected domestic population and the work force population (commercial, industrial and institutional) excluding start-up area are given below.

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Current Status for Water Component: Tenders for 3 LPS (Land Pooling Scheme) zones (Zone 1,2 and 3) out of 13 zones have been awarded and for remaining tendering activity is ongoing. The tenders for trunk infrastructure including WTP and ring main is ongoing. For detailed status, please see end of document.

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2.0 Wastewater infrastructure for Amaravati City Introduction This Detailed Project Report addresses the need for effective sewage collection, conveyance & treatment and disposal system for Amaravati Capital city. The proposed sewerage scheme is formulated based on the latest version of Manual on Sewerage & Sewage Treatment Published by CPHEEO, Ministry of urban Development, Government of India, Year 2013. Details of the system are described in brief as given below. Design Horizon The base year is considered 2020. With Ultimate Plan Year, as 2050, an Intermediate Plan Year as 2035 is provided. The plan period of 30 years with intermediate period of 15 years is in consonance with the design criteria for sewerage schemes. Design Population The present DPR is prepared based on FAR based population projections as it provides realistic estimation of the population based on Land use pattern and Floor Area Ratio of the Master Plan area. Thus, the projected domestic population and the work force population (commercial, industrial and institutional) excluding start-up area are given below

Wastewater Generation

• Per capita Water Supply considered :150 lpcd for Residential & 45 for Workforce • Infrastructure Cushion :10% • Clear Water demand :772 MLD • Sewage generation :80% of Clear water consumption • Infiltration considered :10 % of Sewage generation • Total Wastewater generation :609 MLD (including 9 MLD from DC plants)

Estimation of clear water demand is given in the table below:

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Estimation of wastewater generation is as per below table:

Wastewater Treatment Decentralized sewerage system is proposed due to physical barriers like Kondaveeti Vagu and Palavagu, terrain and ground water table. Accordingly, the city divided into 13 sewerage zones with 12 STPs and 1 CETP. These Zones are generally referred to as LPS (Land Pooling Scheme) Zones, owing to the method of land pooling adopted.

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Zonewise STP capacities Zone Ultimate Capacity (2050), MLD Initial plant capacity, (2035),

MLD Zone – 1 31 15.5 Zone – 2 32 16 Zone – 3 20.5 10 Zone – 4 19 10 Zone – 5 82 41 Zone – 6 26 13 Zone – 7 40 20 Zone – 8 25 12.5 Zone – 9 94.5 47 Zone – 10 36.5 18 Zone – 11 16.5 8 Zone – 12 117 58 Zone - 12A 71 35 TOTAL 611 304

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Wastewater Treatment Three Wastewater treatment technologies namely, SBR, A2O, MBBR or any other technology as deemed fit are proposed after life cycle cost analysis based on life cycle cost analysis.

1. Sequential Branch Reactor (SBR) 2. A2O process 3. Moving Bed Biological Reactor (MBBR) 4. Or any other technology or blend of technologies that suits the given effluent characteristics

with lowest specific energy consumption and low foot print. Treatment Standards to suit recycle requirements The treated water effluent characteristics for Treatment shall conform to BOD <10 ppm, COD <50 ppm, TSS < 10 ppm alongwith Biological Nutrient removal with TN <10ppm, TP <2ppm and Fecal Coliform (FC) <100MPN/100ml to meet the recyclable and reuse standards Wastewater Collection System Wastewater collection system includes lateral, branch, main sewer along with intermediate pumping stations. Total network covered in the capital city is 1017km, out of which length of effective Pipe network is estimated as 966 km excluding manhole coverage length. Minimum size of sewer pipe is 200mm and maximum size is 1600mm. HDPE-DWC pipes proposed up to 490mm and HAC (High Alumina Cement) lined RCC pipes proposed from 600mm and above. The total length of proposed sewerage network is 1017 km. Proposed Sewerage Scheme

The proposed sewerage system consists of 13 sewerage catchments. In every zone, Collection network is proposed to collect the sewage from LPS plots, Non LPS Blocks and villages. The collected sewage will be conveyed to the end location i.e. either STP or Intermediate Pump station (again from here it will be conveyed to STP through gravity network) through Main lines/Trunk Lines. To reduce the depth of

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excavation and ease of laying sewers as the levels of ground water table is higher, network depth is limited to 4.5m/6m (when GWT is higher/lower). Whenever the network depth reaches the limited/restricted depth or unavoidable vagu crossing, an IPS is proposed. The Whole Sewerage system consists of sewer network covering length of 1017 km with pipe diameters varying from 200-1600mm having an effective length of 966 Km, 54 Intermediate Sewerage Pumping Stations and “one Terminal Sewage Pumping Station & one Sewage Treatment Plant particularly for each zone. Wastewater Recycle and Reuse Treated wastewater from 12 STPs and 1 CETP are considered for reuse for Urban Irrigation and District Cooling. The qualities of treated wastewater is complying for District Cooling and urban Irrigation purpose, 29.2% of treated wastewater generated is water requirement for the reuse components. The total quantity of treated wastewater required for urban irrigation and District Cooling is estimated at 157 MLD and 21 MLD respectively. Out of 609 MLD Wastewater generation, 178 MLD of treated wastewater required for Reuse for Urban Irrigation and District Cooling. The balance of 431 MLD planned to be discharged into the navigational canals (Palavagu and Kondaveeti vagu). Minimum diameter 50mm and maximum diameter 600mm with HDPE and DI-K7 pipe used for reuse of treated wastewater. The reuse network is dived into 13 zones and 13 Reuse Water Distribution Center (RWDC)

Effluent Disposal System Out of 609 MLD, 178 MLD of treated wastewater will be used for Reuse for Urban Irrigation and District Cooling and the balance of 431 MLD planned to be discharged into the navigational canals (Palavagu and Kondaveeti vagu). SCADA Supervisory Control and Data Access(SCADA) for IPS, MPS and STP for complete automation of wastewater system.

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Project Cost at DPR level The total project cost for sewerage infrastructure including collection network trunk main, intermediate pumping stations, Main pumping stations, STPs, Outfall sewer, and Reuse Network is estimated as Rs.2592 crores.

Current Status for Wastewater Component : Tenders for 3 LPS zones (Zone 1,2 &3) out of 13 zones have been awarded and for remaining tendering activity is ongoing. The works for STP, MPS, ISPS is part of LPS infrastructure. For detailed status, please see end of document.

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3.0 Stormwater Management in APCRDA, Capital City Introduction For the futuristic city like Amaravati, Storm Water Drainage (SWD) is an important element of

physical infrastructure and constitutes the safe disposal of surplus rain water from the city. However, stormwater runoff from the city areas has the potential to adversely affect the water quality & habitats of receiving waters, stability of existing stream channels and cause flooding of properties. Storm Water Drainage is required to be put in place for an efficient SWD system for a green, sustainable and flood free Amaravati.

A well planned and thought out Amaravati SWD, aims to minimise the impact of urbanisation on the stormwater environment and to strike a balance between social, economic and environmental concerns to achieve sustainable development for the Capital City.

Catchment characteristics Pre development condition. Amaravati Capital City terrain is extremely flat and gently slopes towards northeast leading

towards Krishna River. Existing major vagus namely Kondaveeti Vagu (KV), Pala Vagu (PV) and other streams covers the Capital City region which are originated from South, Southwest or west, draining to Northeast and discharging finally in to Undavalli sluice upstream of Prakasam Barrage.

These streams cause floods during every monsoon season due to existing flat terrain and absence of effective drainage system in to River Krishna due to higher levels of impounded water behind the barrage, resulting in backing up and inundation of considerable areas in proposed Capital City region.

Fig: Catchment area of Kondaveeti Vagu

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The catchment area of Kondaveeti Vagu (KV) is about 421 Sq.km approximately. The approximate length of the main channel of KV is 31.15 Km. The current bed widths of KV vary between 6m to 30m and bed slopes range from 1 in 1700 to 1 in 6500, from Lam village to Krishna River outfall. The catchment has steep slopes at the upstream location of Kondaveedu hills at Perecherla. The slopes fall quickly within the middle catchment area at Tadikonda and become very flat in the lower catchment area from Neerukonda.

Pala Vagu (PV), a tributary, joins KV at Krishanyapalem and there is considerable back water effect on this stream from KV during floods. The length of this stream is about 23.85 Km. Total length of in-falling tributary vagus in to KV are 69 kms approximately. The major streams of KV and PV flow across the Capital City area, currently cause floods in its surrounding region during the times of heavy rains and submerge vast land areas covered in proposed Capital City for several days.

Post development condition. The key challenges namely, flat terrain, existing village settlements, Kondaveeti Vagu (a major

natural drain) flooding, high ground water table, outfall to Krishna River and clayey soils are to be overcome for the design of an efficient and cost effective SWD system for the proposed Capital City area.

Under post development condition, following modifications were proposed in order to mitigate the flooding problem to the proposed capital city.

o Flood discharge from the Upstream side of KV catchment up to Lam reservoir plus the western side of catchment discharge shall be diverted through gravity from Lam reservoir to new reservoirs at Pedaparimi & Vykuntapuram and subsequently to Krishna Nagar.

o The invert level of existing channels were lowered and width of channel increased to lower the maximum flood levels of vagus.

o Vagu’s network under post development condition given below.

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Fig: Proposed Vagu’s network

An Expert Committee was constituted for the scrutiny of concept plan for stormwater drainage system for Capital City and they have met on 30th May 2016. Based on presentation of concept plan & Master Plan, due deliberations during these meetings the recommended design basis parameters finalized and discussed in the sections below. Design Criteria The SWD system for Capital City area is designed duly considering best practices around the

world. The various guidelines for several countries are studied and the optimal designs are finalized.

S.No Country Codes and Guidelines 1 India Manual on Sewerage and Sewage Treatment (CPHEEO) - 2013 2 India Urban and regional Development plans formulation and Implementation

(URDPFI) Guidelines - 2014 3 Singapore Code of Practice on Surface Water Drainage vy Public Utilities Board -2011 4 Singapore Managing Urban Runoff drainage handbook by Public Utilities Board - 2013 5 Malaysia Urban Stormwater Management Manual - 2011 6 Queensland Queensland Urban Drainage manual - 2013

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7 Queensland WSUD Techinical Design Guidelines for South Easat Queensland - 2006 8 UK CIRIA C 687 – Planning for SuDS – Making it happen - 2010 9 UK CIRIA C 687 – SuDS Manual– 2007

10 UK CIRIA C 698 – Construction handbook of SuDS - 2007 11 USA Low-Impact Development Design Strategies – An Integrated Design Approach -

1999

Level of Service: 1 in 5 year return period considered for entire capital city drainage network design and 1 in 100 year return period considered for upgradation of Vagu’s.

Sustainability: The design of drainage systems needs to minimise water pollution and maximise environmental benefits. SuDS units are designed to address stormwater water quality as well as providing hydraulic conveyance. Due to the nature of SuDS units, the consequences of failure tend to be less of a problem than failure of traditional drainage systems. This is because failures of SuDS units tend to be incremental and not catastrophic as in the case of a pipe blockage or collapse.

Cost effectiveness: Principles of whole life costing (figuWLC) should be applied. Drainage design should aim to provide the most cost-effective solution, particularly in terms of maintenance requirements. This requires consideration of whole-life costing of alternative options. In general, the cost of SuDS systems is believed to be comparable to traditional drainage systems. Long-term performance of SuDS units is still being investigated, particularly with regard to the extent of the maintenance needed. “Failure” mechanisms (flooding and pollution) are more robust for SuDS than traditional systems. It should be recognised that any drainage system can fail, whether it is a traditional system or SuDS. Attention to design detail is important to ensure easy and effective maintenance of all drainage systems.

Rainfall characteristics Hourly rainfall data is collected from the nearest rain gauge station available at Gannavaram

airport which is located nearer to the Capital City region. Data is also collected for 46 years (1969 to 2015) from rain gauge station located in and around Kondaveeti Vagu catchments and rainfall analysis is carried out for developing the IDF curves

The rainfall analysis performed using 52 years and 26 years daily rainfall data respectively for Mangalagiri and Thullur indicates an hourly design intensity of 51.55 mm/hr and 50.21 mm/hr for a 5-year return period event. Similarly, with 20 years of hourly rainfall data for Gannavaram Airport, the predicted maximum hourly intensities for a 5-year return period event is 54.77 mm/hr. It is to be noted that very high intensity outbursts of 173.46 mm/hr to 277.37 mm/hr for short duration rainfall of 10 and 5 minutes are predicted for a 5-year return period event. For the predictions of design stormwater discharges for Capital City drains, the 5-year return period hourly intensity of 54.77 mm/hr is adopted as per Gannavaram Airport rainfall station analysis

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Fig: Selected hydrograph of Gannavaram Airport

Flood management of Kondaveeti Vaagu Kondaveeti Vagu flood modelling and management measures study undertaken by Blue Consultant has explored various options for mitigation of floods. For the predicted 1 in 100-year flood flows, cross sections of vagus have been recommended to convey the flood flows. The flood management alternatives include the realignment, widening and straightening of vagus and in combination with the flood flow diverted in to the existing KWD canal (shown as KWDC in map on pg 13) up to restricted capacity of 4000 cusecs via the escape regulator between Kondaveeti Vagu and KWD canal. The rest of the design flood flows from Kondaveeti Vagu shall need to be pumped from upstream of Undavalli outfall sluice. Flood discharge from the Kondaveeti Vagu upstream catchment up to Lam reservoir was diverted by either of the two options. First option is to divert through gravity from Lam reservoir to new reservoirs at Pedaparimi & Vykuntapuram and subsequently to Krishna River. The second option is to divert from Neerukonda reservoir to Krishna River via the Administrative Complex. In the final flood management solution, i.e. Option 1, lowering of Kondaveeti Vagu and Pala Vagu channel bed levels was proposed to facilitate navigation, to bring down the High Flood Levels (HFLs) within the vagus, to drain stormwater from various zones and for efficient storm water drainage of several villages within the Capital City. Preferred alternative of SWD network In-line with the optimal flood management solutions for primary channels (Vagus), there are a few alternatives for stormwater drainage systems for the Capital City based on the type the drains utilized for secondary (Trunk network) and tertiary (LPS zones) drainage network were studied as given below.

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Alternative-1 consists of pipe drains used for the tertiary and secondary drainage network. Maintaining minimum cover criteria for secondary pipe drains has led to outfall invert level going below the HFL of the vagus and it leads to higher fill volumes within the Capital City area. Existing drain corridor in RoW may not sufficient, where there are more number of rows required. Hence, this option of pipe drains is not preferred. Alternative-2 uses pipes for the tertiary drains and grass channels for secondary drainage network. Maintaining minimum cover for tertiary pipe drains for discharging to the secondary/Primary network will lead to higher fill volumes. Grass channels for secondary drains are not possible, cycle track is planned above drain corridor. Hence, this option of pipe drains and grass channels is not preferred. As an Alternative-3, it was recommended that box drains shall be used for the tertiary secondary drains network. As box drains, do not have minimum cover criteria and hence the earth cover is optimized. Maintenance of box drains is easier compared to maintenance of pipe drains. Due to the above advantages, the box drains are preferred and recommended for the Amaravati City SWD. Optimisation of stormwater network The Capital City Storm Water Drainage (SWD) system has been developed with multiple outfall points in to the primary drains i.e. various vagus with the aim of optimising the drain size, drain length and thereby achieve overall economy. Stormwater collected in the tertiary drain network in LPS zones discharged in to secondary trunk drains. Secondary drainage network further connects primary network of vagus. An optimized layout of the trunk main storm water drainage system is designed confirming to the design criteria. Stormwater network is modelled using an industry standard stormwater analysis and design software of SewerGEMS. Following steps were taken to optimize the drain sizes.

• Minimum drain size considered as 450mm x 450mm. • Hydraulic gradient line (HGL) of tertiary drain maintained same as HGL of secondary drains. As

far as possible drops in HGL avoided. • Invert level of secondary drain kept above the Hydraulic flood level (HFL) of vagu’s, where there

is more free board available. • Hydraulic flood level (HFL) of Secondary drains kept above the HGL of Vagu’s.

Current Status for Storm Water Drains : Tenders for 3 LPS zones (Zone 1, 2 and 3) out of 13 zones have been awarded and for remaining tendering activity is ongoing. The tenders for trunk stormwater drains for trunk roads 50m and 65m are awarded by ADC. The flood management works for Kondaveeti Vagu and Pala Vagu is ongoing. Detailed status is given in the subsequent section.

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Status Summary of Development of Potable Water, Sewerage, and Storm Water infrastructure Status of LPS Infra Works

Sr No Area Zone Area (Ac) Drain Length, Km

Status 1 Zone 1 2149 126.25 Contractor Appointed 2 Zone 2 2110.65 142.17 Contractor Appointed 3 Zone 3 2575.46 113.75 Contractor Appointed 4 Zone 4 1768.71 115.542 Tender to be floated 5 Zone 5 5174.54 351.15 Tender floated 6 Zone 6 1768.71 64.63 Tender floated 7 Zone 7 2303.39 142.35 LOA to be issued in next authority meeting 8 Zone 8 Under hold 9 Zone 9 6469.89 532.90 Tender to be floated

10 Zone 10 2356.48 176.18 LOA to be issued in next authority meeting 11 Zone 11 Under hold 12 Zone 12 7837.9 303.63 Tender to be floated 13 Zone 12A 3859.98 232.04 Tender to be floated 14 AGC 1647 80.50 Tender to be floated

List of Under-Construction Trunk Infra Works (Either Infra only or Roads + Infra)

Sr No Description of Package Along Road Road Length (km)

1

Roads, Storm Water Drains, Water Supply, Sewerage and Utility Ducts in E10, E14 and N16 (Package VIII) Roads on EPC Basis in AP New Capital, Amaravati (Package VIII)-- Only Infra works

E10 - Sub Arterial - 50m E14 - Sub Arterial - 50m N16 - Sub Arterial - 50m

Total Length: 23.95 km E10 - 7.81 E14 - 7.36 N16 - 8.77

2

Roads, Storm Water Drains, Water Supply, Sewerage, Utility Ducts in N4, N9 and N14 (Package IX) Roads on EPC Basis in AP New Capital, Amaravati (Package IX) - Only Infra Works

N4 - Sub Arterial - 50m N9 - Sub Arterial - 50m N14 - Sub Arterial - 50m

Total Length: 28.6 km N4 - 7.17 N9 - 13.16 N14 - 8.27

3

Roads, Storm Water Drains, Water Supply, Sewerage, Power Ducts in E6, E8,E12 and N11 Roads (Package X) Roads on EPC Basis in AP New Capital, Amaravati (Package X) - Only Infra Works

E6 - Sub Arterial - 50m E8 - Sub Arterial - 50m E12 - Sub Arterial - 50m N11 - Sub Arterial - 50m

Total Length: 40.24 km E6 - 9.843 E8 - 14.95 E12 - 6.79 N11 - 8.657

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List of Under-Construction Trunk Infra Works (Either Infra only or Roads + Infra)

Sr No Description of Package Along Road Road Length (km)

4

Roads, Storm Water Drains, Water Supply Network , Sewerage Network, utility Ducts for Power & ICT, Reuse waterline, Pedestrian tracks, Cycle tracks, Avenue Plantation & Street Furniture etc. in E2, E4 and N7 Roads in Amaravati Capital City, Andhra Pradesh on EPC Basis. (Package - XI)- Roads +Infra

E2 - Sub Arterial - 50m E4 - Sub Arterial - 50m N7 - Sub Arterial - 50m

Total Length: 32.73 km E2 - 4.44 E4 - 15.555 N7 - 12.742

5

Roads, Storm Water Drains, Water Supply Network , Sewerage Network, utility Ducts for Power & ICT, Reuse waterline, Pedestrian tracks, Cycle tracks, Avenue Plantation & Street Furniture etc. in E7, E9, E11, N3A and N3B Roads in Amaravati Capital City, Andhra Pradesh on EPC Basis. (Package - XII)- Roads +Infra

E7 - Arterial - 50m E9 - Arterial - 50m E11 - Arterial - 50m N3A - Arterial - 50m N3B - Arterial - 50m

Total Length: 36.70 km E7 - 11.568 E9 - 14.117 E11 - 6.31 N3A - 1.452 N3B - 3.258

6

Roads, Storm Water Drains, Water Supply Network , Sewerage Network, utility Ducts for Power & ICT, Reuse waterline, Pedestrian tracks, Cycle tracks, Avenue Plantation & Street Furniture etc. in N8 and N10 Roads (Package XIII) in Amaravati Capital City, Andhra Pradesh on EPC Basis. (Package - XIII) - Roads +Infra

N8 - Arterial - 50m N10 - Sub Arterial - 50m N10 - Arterial - 50m

Total Length: 30.17 km N8 - 13.86 N10 - SA - 5.75 N10 - A - 10.561

7

Roads, Storm Water Drains, Water Supply Network , Sewerage Network, utility Ducts for Power & ICT, Reuse waterline, Pedestrian tracks, Cycle tracks, Avenue Plantation & Street Furniture etc. in E16, N12, N15 and N17 Roads (Package XIV) in Amaravati Capital City, Andhra Pradesh on EPC Basis. (Package - XIV) - Roads +Infra

E16 - Arterial - 50m N12 - Arterial - 50m N15 - Arterial - 50m N17 - Arterial - 50m

Total Length: 28.68 km E16 - 4.465 N12 - 8.633 N15 - 8.514 N17 - 7.078

Page 22: Infrastructure - Andhra Pradesh · Phasing of Infrastructure in line with Organic Growth of City ... (WMD) concept. Total length of pipes of varying ... DI-K9 pipes for diameter of

PAGE 21 OF 21

List of Under-Construction Trunk Infra Works (Either Infra only or Roads + Infra)

Sr No Description of Package Along Road Road Length (km)

8

Roads, Storm water Drains, Culverts, Minor/Major Bridges, Water Supply including head works (Intake well, Raw water pumping main, Water treatment plant, Cushion tanks and Semi underground reservoirs, Integration with entire water supply and other ancillary works), Sewerage, Power and ICT conduits, RCC duct for Power cables, gas crossings, Cycle tracks, Street furniture and Avenue plantation, O&M of 10 years for Water Supply including Head Works for Road No.E3 (Package-XV) in Amaravati Capital City Area, Andhra Pradesh on EPC Basis. -Roads +Infra

E3 - Sub Arterial - 60m 18.27 km