Anil Agarwal Environmental Institute, Nimli village, Tijara block, district,

Nimli village Jaipur RAJASTHAN

Map with RWH structures

Water requirement at AAETI (in KLD)

35(48%) 31(42%) Water balance chart Water Freshwater 80-85% of Groundwater Domestic water domestic required for required for recharge 10,302 KL requirement (Non- wastewater Irrigation Building flusing) 5,846 KL 5,677 KL Waste water treatment Stored rain wate 7(10%) Domestic water units 732 KL Water required for Flusing requirement (Flusing) 1,900 KL

Total area of the Site: 39,100 Sq. m Reuse of treated effluent 5,590 KL Water requirement for HVAC system Catchment Catchment for 1,920 KL for rainwater groundwater storage recharge Horticulture water requirement 8,870 KL

Treated Area = 39,100 sq m Total supply Total consumption wastewater Located 120 km southwest of 16,624 KL 18,536 KL generation @ 85% Annual rainfall = 550 mm Total water requirement = 73 KLD Only 50 per cent will be extracted from Rainwater storage the groundwater and the rest will be Collection Potential(KL) sourced from recycled wastewater and Roof Area Building Monsoon stored rainwater (Sq.M.) 1 Day* Yearly*** Season** 1) Academic 604 48.9 239 299 Groundwater recharge potential Block Catchment harvested for groundwater 2) Cafeteria & 845 69.17 338 423 recharge = 37462 sq m Recreation Co-efficient of runoff = 0.55 Total 1,458 118.07 577 732 Annual recharge potential =10,302 cu m IT TAKES MORE MONEY TO SUPPLY WATER, THE FURTHER...

City Source Distance Cost to supply (Rs/kl)

Aizawl River Tlwang 1,000 metres down the valley, 18 km away 53.90 Bengaluru River Cauvery 100 km from the city 12.70 Chennai Lakes, groundwater and Veeranam lake 60-235 km 11.60 of bad health: waterborne diseases remain the planning as well as spending. While building a Delhi River Yamuna and groundwater Across the city 8.70 Indore River Narmada 70 km 11.00 biggest burden on the country’s health system. sewage network is part of capital expenditure, Jodhpur Indira Gandhi Canal 205 km 8.70 Clearly, these costs are not imaginary and must the cost of its refurbishment is not. All costs, of MussoorieWater Springwater: Bhilaru, managers Jinsi, Khandighat, 6-7 kmmay down the valley not know 16.80where the The official leakage loss in is 40 per Murray, Mount Rose and Dhobighat be factored in. pumping and treatment, are combined and Mumbai‘missing’ Bhatsa, Vihar, Tulsi, Tansa,water Upper Vaitarna has 100-110 gone, km but they 10.70have Water agencies rarely havecent, a separate and budget as high as 44covered per within cent the in overall Jaipur costs where of operations. Hyderabad RiverCities Krishna 116 km and6.40-18 water supply kl: kilolitre head for this component of its work. It therefore It is, therefore, difficult to assess what these Source: Anon 2011, 71-City Water-Excreta Survey, 2005-06, Centre for Science and Environment, New Delhi 16 studiously defined its characteristics. Non-remains the most neglected, inas terms much of as 153 MLD waterare and will is belost in the in future. distribution revenue water comprises three components: Componentsinefficiencies. of Similarly,water supply in the desertin city of

■ Physical or real losses from leakagesChennai fromCOMPONENTS OF WATERdiffernt SUPPLYJodhpur, IN DIFFERENT cities where CITIES (In water (IN%) PER CENT)is sourced from the Indira 18km all parts Bengaluruof the system; Gandhi Canal at considerable cost to the city, ■ Commercial losses because235 of km faulty or losses amount to 20 per cent. non-existent billing and theft; Let’s understand how some 2cities deal with

■ Unbilled but100 km authorised consumption for their water-maths. 23 Dehradun 71-Cities 28 public purposes, such as firefighting. 2 1.4 Average In Indian cities nobody knows where the 10 22 24 54 71-CITY 33SURVEY: MISSING MILLIONS (IN MLD) water goes missing, for there is no billing, only Delhi 1.5 24

Waterhuge requirement leakages everywhere. at So these sums do not Jodhpur 52 0.5 3 1 Agra AAETI (in KLD) 5 really matter. Jaipur 5 ...AND FURTHER A CITY GOES IN SEARCH OF IT 0.38 Source: Anon 2011, 71-City Water-Excreta Survey, 2005-06, Centre for Science and Environment, New Delhi 17 0 25 8.7 77 46 224 | EXCRETA MATTERS Water requirement at Augmentation20 needed 2005-2011 6,151 54 Lost water = less water AAETI (in KLD) 37 4 Vadodara 2 4 0 1 It is this ‘lost’ water that leads to scarcity. In the 0 Indore 22 105km 20 71 cities CSE surveyed, the average distribution 60 74 Total17 water loss, 2005 6,877 80km water loss in 2005 touched 35 per cent, Mumbai 1 2 3 Aurangabad Srikakulam 9 11 translating to a staggering 6,877 MLD. ‘Staggering’ 17 5.4 19 4 7 67 59 27 because205 km these cities lost, in just one year, enough Pune Hyderabad 0 0In 2005,0 35%1 of30.5 the official water 5 31 water to take care of their requirements116km for 22 73 27 37 supply1 of 71 cities got ‘lost’ in augmentation till date (see Graph: 71-city survey: 9 35 140 km 14 60 Missing millions). transmission.16 1.3 Of the 71 cities, water20km supply in 35 per cent Bengaluru Chennai 12 Energy is in excess of demand, calculated on the basis The water52 ‘lost’23 in just one year is Salary of the CPHEEO water supply norm. But once the 10 more than all the extra waterRepairs these distribution losses, as estimated70km by different cities required by 2011. Chemical water supply agencies, are accounted for, less Others than 24 per cent cities have adequate water 32% of water supply was needed in Source:supply Anon 2011, 71-City Water-Excreta (see Survey, 2005-06 Table:, Centre for Science and71-city Environment, New Delhi survey: How leakage Source: Anon 2011, 71-City Water-Excreta Survey, 2005-06, Centre for Science and Environment, New Delhi lossesEnergy create costs the real shortfall...MakeFAECONOMICS COSTS: ELECTRIFYINGsupply). | 225 Water additionalWater is lostdemand in Water areThis highest means there is lessexpensive water in the system220 | EXCRETAhighway MATTERS distribution, But then inequity to distribute as well. In Agra, for instance, component of leaks at MLD:this Million water litres daily is distributed grows where there is as much Difficultas 171 LPCD toof water to Source: Anon 2011, 71-City Water-Excreta Survey, 2005-06, Centre for Science and Environment, New Delhi distribute,water supply after losses onlyreach 94 LPCDall remains. both ends to less people

71-CITY SURVEY: HOW LEAKAGE LOSSES CREATE THE REAL SHORTFALL IN WATER ACTUALLY SUPPLIED

Demand Supply Gap in Shortfall Leakage Supply Demand- Shortfall in 2005 2005 2005 in supply, loss after loss, actual supply actual supply, MLD MLD MLD 2005 (%) MLD 2005 (MLD) gap, 2005 (MLD) 2005 (%) Metro 17,987 16,591 1,396 8 6,150 10,441 7,546 42 Class I 2,879 2,775 104 4 706 2,069 811 28 Class II & III 129 123 7 6 21 101 28 22

Total 20,996 19,489 1,507 8 6,877 12,611 8,385 40

MLD: Million litres daily Source: Anon 2011, 71-City Water-Excreta Survey, 2005-06, Centre for Science and Environment, New Delhi

38 | EXCRETA MATTERS How to audit for rainwater harvesting?

Catchment details: Area, type and nature Calculation of the rooftop area Meteorological data: Get average annual rainfall, intensity and spatial distribution Geological and Hydrogeological data: Nature of rocks soil, aquifer and physiography User water profile: Total water requirements, proportion already available, source of availability Objective of the system and what are the uses (length = l; breadth = b); Budget available and tentative cost: Legislation and l x b = area incentives available

How much rainwater can be collected? Storage and recharge in Bhopal’s Deccan trap Total volume of water = area X four, consuming 540 litres/ run-off coefficient X rainfall day = 540 X 365 = 197,100 Area = length X breadth = 20m litres/year X 10m = 200sqm 3) Water demand, family of four, Run-off coefficient of roof = 0.8 the three driest months = Annual rainfall =500mm 540 X 90 = 48,600 litres 1) Rainwater harvesting 4) Water demand for toilet potential = 200 X 0.8 X 500 flushing and gardening = 80,000 litres (yearly) at 180 litres/day 2) Water demand, family of =180 X 365 = 65,700 litres

Standard site plan (before RWH) Run-off coefficient for different types of catchment Catchment Type of material Run-off coefficient Tiles 0.8-0.9 Roof Metal 0.7-0.9 Concrete 0.6-0.8 Paved area Driveway/courtyard, roads Brisk 0.5-0.6 10% sand 0.0-0.3 Unpaved area garden, playground Hard compact 0.2-0.5 Lawns 0.1

Hydro-geological conditions and type of structure Parameter Type/condition Recommended structure Impermeable, nonporous, non- Nature of aquifer Storage homogeneous, hard rock area Depth of groundwater More than 8 meters Recharge and Storage Site plan (after RWH) table Hilly, rocky or undulating Storage Nature of terrain Uniform or flat, alluvial and sedimentary Recharge and Storage Alluvial, sandy, loamy soils, gravel, silty, Recharge and Storage Nature of soil with boulders or small stones Clayey soil Storage Massive rocks (such as Deccan trap) Storage Nature of geological Fractured, faulted or folded rocks, or formation comprises of weathered, jointed or Recharge and Storage fissured rocks Number of rainy days are more, bimodal monsoon, not intensive, uniformly Storage Nature of rainfall and distributed monsoon Unimodal monsoon, rainfall available Recharge and Storage only for a few months Recharge techniques Characteristic for different recharge structures Recharge pit Recharge pit Recharge Pit Recharge well Recharge trench (with bore) Used in places Where the top layers From paved ground where soil is of soil/rock may not For large catchments catchments such as sandy be permeable near gates Shallow pit lined with Has a settlement tank, bricks on the sides. a sump filled with Large trench with Shallow pits Filled with filtering filtering materials and filtering materials Recharge pit with bore material and has a one or more recharge and recharge bores recharge bore-pipe bore-pipes No constructed No-constructed base. base, open Constructed base. Casing of tubewell (top), slotted pipe (below) Open to the soil to the soil Constructed base. Note Not open to the at bottom with a at bottom, open to the soil soil. Metal grill perforated cover on perforated cover top cover on top Design consideration: Design Design consideration: Recharge trench with bore Design Settlement tank to consideration: Availability of consideration: slow down the water Volume of trench permeable layer at permeability of flow. Length of bore- to exclude space relatively shallow soil pipe should be above occupied by filtering depths groundwater level material

Thumb Rule For Recharge Structures Do not recharge soils that toward the foundation. Recharge well with settlement tank Recharging in-use borewells and dugwells have a heavy content of Good soils for recharge clay, which expands when are sand, loan, loamy sand wet and shrinks when dry. and sandy loam. This can cause damage to Ensuring the quality building foundations of water recharge of Do not recharge if the water recharged is a very land slopes towards a important consideration for building. Water will run recharge systems.

Sizing of recharge structure Volume of water during most intense period of rainfall determines size Good practice Description Delhi Mumbai for recharge Catchment area 100 sq m 100 sq m The recharge bore should Duration of intense spell 15 minutes 30 minutes never reach the aquifer. It should terminate some way Average peak intensity of rainfall/hour (based on 25- 64 mm 100 mm above the water table. year average) Run-off co-efficient (average of different types of 0.6 0.6 This ensures that the water catchments) being recharged is further Volume of water generated x peak rainfall x co- 100 x 16 x 0.6 = 960 100 x 50 x 0.6 = 3,000 litres filtered through sufficient efficient litres thickness of soil before reaching the aquifer. Recharge pit volume: 2/3 of rain volume 640 litres 2,000 litres Dimensions of recharge pit (l) x (b) x (d) 1 m x 0.75 m x 1 m = 1 m x 1 m x 2.5 m = 2,500 litres As a thumb rule, the depth 750 litres of the bore should be above the postmonsoon level of Space for filter materials and the invert level* 750 – 640 = 110 litres 2,500 – 2,000 = 500 litres groundwater. *Note: The invert level is the depth at which the incoming pipe joins the recharge pit will have to be taken into account to calculate desired dimensions

Stages of construction of a recharge well, Delhi Gymkhana Club Recharge techniques Maintaining tips

Poorly maintained structures

Keep the catchment area clean

Rooftop covered over by leaves Cracked downtake pipe Downtake pipe not connected to the roof

Keep the outlets clean

Settlement chamber filled with debris (malba) Broken conduit system Cracked RCC cover of a recharge well

Step by step cleaning of recharge structures

Keep the gutter securely fixed

Remove parts of recharge trench for cleaning Remove silt from recharge bore Remove filter material (pebbles) from pit

The filtertannk needs to be kept clean

Wash the filter material Clean recharge bore and filter material Put back the parts of the recharge trench

Amrish Bhai Vaisav, Residence of Junagadh, Gujarat. Using the system for many generations The storage tank needs to be washed

First flush: The left outlet is plugged with cloth during the initial rains. The first flush of rainwater flows into the other outlet wich leads into a stormwater drain outside the house. Crystal clear water in the bucket drawn from the tanka Down the generations, grandmother and granddaughter Water is later diverted into the tanka drawing water from the tanka The trench has to be free of debris Monitoring Residence of R. Ramani Chennai System details Total rooftop area: 108 sq m Volume of storage tanks: 6,000 litres (3,500 overhead tank – civil) + 500 (Sintex) + 2,000 (GL sump) Filter media: 1-2 inch size pebbles (at bottom), charcoal, coarse sand and half-sieved river sand (on top). No of filter tanks: 5 (1 collection-cum-filtration tank; 2 Sintex tanks, 200 litres capacity each with charcoal, pebbles); 1 Sintex tank, 50 litre capacity each with charcoal, pebbles; 1 ground-level filtration tank) Recharge structures: Open well, 2 recharge wells, 2 percolation pits Cost: I60,000 in the year 1988 Designed and implemented by: R Ramani, Chennai

Water quality of stored water at Junagadh, Gujarat System details Microbiological test results Water quality of the tank Total area: 1,064 sq m Parameters Units Permissible 1994 1999 2012 Parameters Permissible limit (mg/l) Test results (mg/l) Storage system: 1 pH — 6.5 - 8.5 7 7.1 7.6 pH 6.5 – 8.5 7.33 Underground sump (volume): Turbidity NTU 10 5 2 2 Total dissolved solids (TDS) 2,000 500 100,000 litres Total dissolved solids mg/l 2,000 3,325 1,335 970 Total hardness (as CaCO3) 600 160 Recharge system: 1 Total hardness mg/l 600 900 540 370 Total alkalinity (as CaCO3) 600 120 Recharge well: 2.5 m x 2.0 m (as CaCO3) Calcium (as Ca) 200 32 x 3.0 m Total alkalinity mg/l 600 380 420 344 Magnesium (as Mg) 100 19 Recharge bore: 165 mm dia, (as CaCO ) 200 m deep 3 Chloride (as Cl) 1,000 160 Iron (as Fe) mg/l 0.3 NIL trace trace Cost: I4.73 lakh Sulphate as (SO4) 400 36 Note: Sample of 12.5.94 was tested in S & S Industries & Enterprises, Madras; Nitrate (as NO ) 45 34.3 Date implemented: 2005 Sample of 9.4.99 was tested in the water analyst’s lab of Chennai MetroWater; 3 Designed and implemented Sample of 6.1.2012 was tested in the water analyst’s lab of Chennai Fluoride (as Fl) 1.5 0.4 MetroWater by: Gujarat Water Supply and Notes: mg/l: milligrams per litre, CaCO3: calcium carbonate; tested: January 2012; Sanitation Board, Junagadh Source: Unit Manager, Coordination, Monitoring and Support Unit, WASMO, Junagadh

Harvesting rain in hard rock in individual residence Arunachalam, Madurai, Tamil Nadu

System details Roof area: 174 sq m Storage system: 1 Storage tank: 3.66 m x 1.22 m x 2.44 m (stores 10,895 litres) Recharge system: 1 recharge pit (90 cm dia, 3 m depth) Year implemented: 2006 Cost: I44,000 Designed and implemented by: N Arunachalam

Rainwater is used for drinking and cooking IMPACT: The family’s monthly cooking and for this family of four the year round. The drinking water demand is about 600 litres. municipality does not provide water and the The underground sump collects enough area is entirely dependent on groundwater water for the whole year. Monitoring Harvesting rain in colony East Nizamuddin Colony, New Delhi

Rainwater in the stormwater drains was tapped to recharge groundwater. This was an effective antidote to waterlogging

System details Total rooftop and surface area: 2.01 lakh sq m Collection chambers (1 per recharge structure): 0.45 m x 0.45 m x 0.5 m A waterlogged lane in the colony Recharge pits (11): 1 m x 1 m x 2 m Recharge bore: 10 m deep with 150 mm dia Cost: I1.79 lakh Designed by: Centre for Science and Environment, New Delhi; Implemented by: Resident Welfare Association, Nizamuddin (East)

IMPACT: The system was completed in 2004 and the residents could soon see

the results. Waterlogging has reduced Harvesting the rainwater from the stormwater drain greatly in the colony. has stopped flooding

Harvesting rain in hard rock in colony Rainbow Drive Colony, Bengaluru, Karnataka

Stormwater drain network was harnessed System details to initiate a rainwater Total area: 137,593 sq m harvesting system across (34 acres) Area of unpaved surfaces the colony (15 per cent of total area): This colony has thought beyond rainwater 20,639 sq m Number of houses: 240 harvesting. Its residents have optimised on the Recharge wells (20 in use of rainwater, through recharge, discounts stormwater drains, 51 in on water bills and a water tariff system that homes): 71 (3 ft dia, 20 ft accounts for costs of treatment, supply and deep) Volume of wells: 2.84 lakh sewage treatment. litres Designed by: Biome Environmental Solutions Quality water from sewage Pvt Ltd, Bengaluru In 2011, the colony residents approved a Implemented by: plan to set up a new sewage treatment plant Rainbow Drive Residents’ Welfare Association (STP) based on soil biotechnology, developed at IITMumbai. This technology will provide A recharge well in a stormwater drain. The jelly stones desilt the water before it river quality water for reuse as opposed to enters the well conventional methods which treat water for Innovative tariff to disposal. The colony intends to supply this discourage wastage of water water for non-potable use to all residents To enforce conservation, the as well as sell it for use in constructions to residents of Rainbow Drive have Table: Slab-based water tariff recover the cost of the STP. introduced a tariff system that Water consumption level Tariff (I/kl) charges users for the true cost of First 10,000 litres (0-10 kl) 10 water. Charges are based on cost IMPACT of treatment, supply and sewage Next 10,000 litres (10-20 kl) 15 The wells have a total volume of 2.16 lakh treatment. The slab-based tariff Next 10,000 litres (20-30 kl) 25 litres and hence can recharge multiples of 2.16 discourages wastage. Private Next 10,000 litres (30-40 kl) 40 lakh litres at the time of each rainfall. From a borewells have also been banned. Above 40 kl 60 situation where only one of six borewells was An incentive is also in place – Source: Rainbow Drive Residents’ Welfare Association yielding water, today water is pumped out residents with recharge systems from three borewells which have enough water get a discount of I100 on their even in summer months. water bills.