SHAKUNTHALA BAI and S.SRIKANTASWAMY Department of Studies in Environmental Science, Manasagangotri, Mysore

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1 Lake 2008 Conference, IISc, Bangalore 22-24,December 2008 WASTE WATER TREATMENT AND MANAGEMENT IN URBAN AREAS A CASE STUDY OF MYSORE CITY. SHAKUNTHALA BAI and S.SRIKANTASWAMY Department of Studies in Environmental Science, Manasagangotri, Mysore

2 Urban waste water components UWW means domestic waste water, consisting of blackwater - excreta, urine and associated sludge and greywater -kitchen and bathroom wastewater or the mixture of domestic wastewater from commercial establishments and institutions including hospitals with industrial wastewater and run-off rain water. Non point sources include silt from earth-moving activities; iti storm runoff from roads, home gardens, and industrial sites, infiltration from aquifers contaminated t with domestic waste water or industrial chemicals; and automobile emissions.

3 Heavy metal in Urban waste water The sources of metal pollution in the UWW system can be classified into three main categories: Domestic. Small scale industries (connected to the Waste Water Treatment System) and commercial. The other principal p sources of metals in UWW are body care products, pharmaceuticals, cleaning products, tanneries, metal smelting units, jewellery industry and liquid wastes. Wastewater e often contaminated with industrial effluent contains high levels of heavy metals.

4 Mysore According to the 2001 census of India, the population of Mysore is 7.86lakhs and it is estimated 12lakhs population by Mysore has adequate water supply resources due to the proximity of Rivers Cauvery and Kapila. a. The city has four pumping stations (source: KUWSDB) The quantity of domestic waste water generated has increased from 80 MLD during 2001 to 128 MLD during The area covered with sewer system is 100 Sq. kms and the total t length of sewer lines is 740 Kms. Only about 57% of the household are connected to under ground drainage system.

5 Waste water generation and treatment Mysore was one of the earliest cities in India to have underground drainage. In old parts of the city underground drainage was completed in The topography of the city is such that the entire city drains into three valleys viz., northern outfall into Kesare Valley, and other outfalls to the south one into Dalvai tank feeder valley and another to Malalavadi tank valley. Mysore city comprises of five drainage districts, namely, A, B, C, D and E During the year , 07, the quantity of UWW generated is 128 MLD and 95 MLD is treated. The untreated and treated UWW is largely used for irrigation. (Source: MCC).

6 Waste water treatment plants at Mysore: The city has been provided with three waste water treatment plants. All of them have facultative aerated lagoons and sedimentation basins with capacities as detailed in Table 1. Table 1: Waste water treatment plants and sampling stations Sl. No. Draina ge district s Location of WWTP 1 A&D Rayanakere, 2 B Sewage farm, Total capacity of the WW treatment plant in MLD Areas Rayanakere, RMP Quarters and Aravind Nagar, VV Mohalla and H.D. Kote road, Janatha Nagar Mysore Vidhyaranyapu arm, Mysore South, Mysore 3 C Kesare Village, Mysore Surrounding areas of Kabeer road, Ashokpuram, Dhanavanthri Road, CFTRI, Chamaraja Double Road, JSS, Kanakagirinagar and Gundu Rao Nagar Surrounding areas of Yadavagiri, Kumbara Koppalu, B.M.Shree Nagar, Metagalli, Pulikeshi road, C.V Road, Subash Nagar,Kesare, Hebbal 1st stage, Adhidravada Paurakarmika Colony, CFTRI Quarters, Rajivnangar 3rd stage, V.V.Mohalla, Gokulam, Gandhinagar, Sathyanagar, Hebbal

7 Missing Links The area covered with sewer system is 100 Sq. kms and the total length of sewer lines is 740 Kms. Only about 57% of the household h are connected to under ground drainage system The fifth drainage district i t E in the city covers an area around 16sq.kms. does not have a waste water treatment system. There are several missing links at each district and 30 MLD is discharged as such on land, in low lying areas, which joins water bodies. The total length of missing sewer line identified is about metre. (Source: MCC).

8 Table 2: Seasonal variation of Physico-chemical chemical characteristics Station No Parameter Summer Monsoon Untreated Treated Untreated Treated 1 p H E.Cond (ds/m) BOD(mg/l) SAR TDS(mg/l) p H E.Cond (ds/m) BOD(mg/l) SAR TDS p H E.Cond (ds/m) BOD(mg/l) SAR TDS The Seasonal variations of Physico-Chemical parameters indicated higher values during summer than during monsoon.

9 Table 3: Physico chemical Characteristics of UWW at waste water treatment e t plants of Mysore Sl No Location ph E.Cond (ds/m) BOD (mg/l) TDS (mg/l) SAR(meq/l) Raw Treated Raw Treate Raw Treate Raw Treate Raw Treate d d d d 1 Station No. 1 2 Station No. 2 3 Station No. 3 FAO (1985) irrigation standards (slight to moderate hazard) < (slight to Moderate 3-9 Hazard)

10 Physico-chemical chemical characteristics E.Cond (ds/m) Raw E.Cond (ds/m) treated 0 Station No. 1 Station No. 2 Station No. 3 ph in all the three Lagoons is within the limit as prescribed by the FAO irrigation water quality standards with slightly more at station No.3 ( ). The BOD in the inlet is high as of the organic content and in the city wastewater, it is usually high. After biological treatment in the Lagoons, it has been reduced. The EC value is obviously attributed to the salts used in the process of cooking and washings. EC values of untreated and treated waste water at all the three stations lie within the slight to moderate hazard range of the FAO irrigation water quality standards. At Station No. 3, EC is higher in the treated waste water, which is because of presence of suspended materials along with the salts, which are not settled completely

11 Station No. 1 Station No. 2 Station No. 3 TDS (mg/l) Raw TDS (mg/l) Trea ted TDS in all the three Stations is within slight to moderate hazard limits. Sodium Absorption Ratio(SAR) indicates the effect of relative cation concentration on Sodium accumulation in the soil. SAR in the untreated and treated waste water is within the slight to moderate hazard. Using water having higher SAR can lead to a breakdown in the physical structure of the soil.

12 Table 4: Heavy metal content of UWW(ppm) Stati on Nos. Metal Cu Fe Zn Pb Ni Cr Cd R T R T R T R T R T R T R T 1 TM 0.01 ND 0.40 ND ND ND ND ND DM 0.02 ND ND ND ND 2 TM 0.02 ND ND ND ND ND ND ND DM ND ND 0.82 ND 0.09 ND 0.07 ND ND ND ND 3 TM ND ND ND ND ND ND ND DM ND ND 0.67 ND 0.01 ND ND ND ND ND R- Untreated UWW. T- Treated UWW. TM-Total Total Metal DM-Dissolved Dissolved metal

13 Heavy metal content The practice of wastewater irrigation is widely adopted by poor farmers around urban area. These wastewater is often contaminated with industrial effluent that contains high levels of heavy metals. The concentration of heavy metals Cadmium, Chromium, Zinc, Copper, Nickel, Iron and Lead in both untreated and treated waste water was monitored. Cadmium, Nickel and Chromium were not detectable. The heavy metals like Copper, Iron, Zinc and dl Lead were decreased d at tth the treatment t t plant.

14 Types of Reuse of Waste Water The treated and untreated UWW is mainly used for Agricultural use For Irrigation of non-food and food Crops. Aquaculture use For fish cultivation Recreational impoundments such as ponds and lakes

15 CONCLUSION Total Dissolved Solids, Electrical Conductivity and heavy metal concentration and other water quality parameters are unfavorable, but we can observe the reduction of fbod BOD. The treatment process is not adequate as only primary treatment methods are carried out. Undesirable effects include that the entire quantity of urban waste water generated at Mysore city is not fully collected for treatment and most of the untreated t waste water finds its way into water bodies and on agricultural l land thus resulting contamination of water bodies and soil pollution. Application of untreated ed wastewater e for irrigation water may result in groundwater contamination. Determination of water quality of water bodies receiving urban waste water and post-irrigation impact of UWW on composition of soils, crops needs further studies.

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