Kadodara Creek

This creek receives treated effluent from CETP PEPL (Palsana Enviro Protection Ltd.) having a capacity of 150 MLD and also joins the Koyli creek before meeting the estuary (Figure 9.1). From the list of parameters for assessing the quality of water, DO and TCOL are not measured for this creek and only pH and BOD have been assessed for a few months between 2008 and 2013. After that, monitoring has been discontinued by the GPCB. The analysis of the quality of water in this creek is presented in Table 9.4. Here it is clear that water quality does not meet the desired levels downstream of the CETP discharge, as the values of the BOD are very high. Only the pH is seen to be within limits. However, at the upstream of the CETP discharge point, the values of the BOD are below the permissible level of 3.0 mg/1. The pollution in the creek can thus be attributed to the discharge from CETP PEPL. Since the observed values for the BOD are above the

TABLE 9.4 Water quality in the Kadodara Creek

Kadodara Creek at causeway on Jolva—Parab Road (Upstream of the CETP)

Source: Unpublished data from GPCB.

permissible value of 30 mg/1 for treated effluents from the CETP, it raises a question mark over the performance of the CETP in meeting the prescribed standards.

Koyli Creek

The Bhedwad creek and the Kadodara creek flow into the Koyli creek. The monitoring point for this creek is on the Sachin—Magdalla road as shown in Figure 9.1. The analysis represents water quality after discharge from two large

TABLE 9.5 Water quality in the Koyli Creek

Source: Unpublished data from GPCB.

CETPs—Pandesara (100 MLD) and PEPL (100 MLD)—and most of the STPs in Surat. In spite of the fact that this creek receives major industrial and sewage discharge from the city, the quality of water in this creek is not monitored. The analysis details are available only for a few months in 2008 and 2013. From the list of parameters included in the designated best use criteria, only pH and BOD are measured, and the details are presented in Table 9.5. The values for the BOD show that this creek is highly polluted and the values for pollution levels are comparable to those in the Sabarmati in Ahmedabad. This raises a serious question mark on the effectiveness of the STPs and CETPs in treating domestic and industrial pollution respectively.

Unn Creek

This creek receives the treated effluent from two CETPs, both located in GIDC Sachin—CETP SIEL (Sachin Infra Environment Ltd.), which is designed for the treatment of industrial effluents from textile units and CETP GECL (Globe Enviro Care Ltd.), designed for treating industrial effluents from chemical units. It does not receive discharge from any STP. The creek was being regularly monitored during the period from 2008 to 2010, but it was later discontinued by the GPCB. The pH is found to be within the permissible limits. The details of the analysis for the BOD is presented in Figure 9.2. The average BOD value is 9 mg/1 and is not very high when compared to the quality of water in the other creeks. This is quite surprising as the other creeks, e.g. the Koyli creek, which receives the industrial and domestic discharges, show high levels of pollution. This raises a doubt as to whether there is illegal discharge from industries located in this area to another water body/bodies.

FIGURE 9.2 BOD in the Unn Creek. Source: Unpublished data from GPCB.