CETPs in Ahmedabad

The city has six CETPs, the details of which are summarised in Table 8.2.

The CETPs in Ahmedabad differ from each other in terms of capacity, number of member units, type of effluent and the mode of transportation of the effluents to the respective CETP. GIDC Vatva, with 16 MLD⁴ capacity, is the largest CETP in Ahmedabad. This CETP treats heterogeneous effluents from industries manufacturing such things as dyes, dye-intermediates, chemicals, textiles and food products. The industries send their effluents to this CETP via an underground pipeline. The CETP is operated and managed by the Green Environment Services Cooperative Society Ltd., a society formed by all the

MAP 8.1 Ahmedabad with location of industries, CETPs and discharge points.

member units. CETP Naroda is the second largest CETP in Ahmedabad, with a capacity of 3 MLD. It is operated and managed by the Naroda Enviro Projects Ltd. (NEPL), a registered company under Section 25 of the Companies Act. There are 220 industrial units which are shareholders of the company. The CETP treats heterogeneous effluents from a mix of industries like dyes, chemicals, textiles and food. This CETP receives wastewater from industrial units by an underground pipeline. Dedicated tankers are also used to transfer effluents to the CETP from the parts of the estate where the pipeline has not been laid (Phase III of GIDC Naroda). The concentrated effluents (COD⁵ > 3000 mg/1) in Vatva and Naroda are received through tankers and are treated separately in a multi-effect evaporator (MEE). CETP Odhav Enviro Project Ltd. (OEPL), with

TABLE 8.2 CETPs in Ahmedabad City

Source: The table has been compiled from the data collected from different sources (GPCB Annual Reports; Discussions with the CETP Operators; Consent Orders of the CETPs).

Note: The treated effluents from all the CETPs are conveyed through pipeline for final discharge into the Sabarmati.

a capacity of 1.2 MLD, has 60 members and treats heterogeneous effluents from member units belonging to chemical manufacturers, dyes and dye-intermediates etc. CETP Odhav Green Enviro Project Association (OGEPA) has a designed capacity of 1 MLD, though the capacity being currently utilised is only half of that. It has only two members from the textile sector. CETP Gujarat Vepari Maha Mandal (GVMM) has mainly rolling mills as member units but as some of the members are engaged in the manufacture of dyes, dye-intermediates and chemicals, it treats heterogeneous effluents with a capacity of 1 MLD and the effluents get transported through pipelines. The capacity of CETP Narol, which is the smallest amongst all the CETPs studied in Ahmedabad, is only 0.1 MLD. The effluents to this CETP are mainly transported through pipelines, as well as tankers, for some units. Other textile units in Narol, about 125 in number, treat their effluents in individual effluent treatment plants. The planning process for another CETP for Narol, with a larger capacity, is in progress at the time of writing.

The treated effluents from all the CETPs are discharged into a mega pipeline for final discharge into the Sabarmati. This pipeline has a length of 27 km, with a carrying capacity of 90 MLD and has been operational since 2001. Before 2013, industries in Narol also used to discharge their treated effluents into this pipeline, but later, a separate pipeline of the Ahmedabad Textile Processors’ Association (ATPA) was laid, with a capacity of 100 MLD to carry the treated effluents from the textile units located in Narol. Currently, an average effluent load of 75 MLD is being conveyed by the ATPA pipeline for final discharge into the Sabarmati.