BIS’ Draft Standard For Drinking Water Supply
The Bureau of Indian Standards (BIS) has prepared a draft standard for the supply system of piped drinking water and has invited comments from water utilities, including the Delhi Jal Board (DJB), on it.
- Labelled ‘Drinking water supply quality management system — requirements for piped drinking water supply service’, the draft has been prepared by the BIS’ Public Drinking Water Supply Services Sectional Committee.
- It outlines the process of water supply, from raw water sources to household taps, and has been developed keeping in view the Centre’s Jal Jeevan Mission for providing safe and adequate drinking water to all rural households by 2024 through tap connections.
- The standard holds importance as it is expected to make the process of piped water supply more uniform, especially in rural and underdeveloped areas of the country where the system runs on various government orders and circulars.
- At present the standard is not expected to be made mandatory. After the draft is notified, states or water utilities planning to implement the standard can approach BIS for a license.
What does the draft say?
- The draft outlines the requirements for a water supplier or a water utility on how they should establish, operate, maintain and improve their piped drinking water supply service.
- The process begins with identification of a water source, which can either be groundwater or surface water sources such as rivers, streams or reservoirs. It doesn’t mention how water utilities should treat the water, but states that the process should be planned in such a manner that after treatment the drinking water should conform to the Indian Standard (IS) 10500 developed by the BIS.
- The IS 10500 outlines the acceptable limit of various substances in drinking water, including heavy metals such as arsenic, and other parameters like the pH value of water, its turbidity, the total dissolved solids in it, and the colour and odour.
- The draft standard also contains guidelines for top management of the water utility, in terms of accountability and customer focus, establishing a quality policy for their service, monitoring the quality of water released to people, and conducting a water audit.
What is the water supply process?
- The supply system as outlined in the draft should begin with the identification of a raw water source. Water should then be pumped into the treatment plant and treated to achieve the acceptable drinking standards.
- After the water is released from the plant, there should be reservoirs in the distribution system for storage of this water, and disinfection facilities to get rid of contamination at any stage of distribution.
- “Pumping stations or boosters, if necessary, should be provided to maintain adequate pressure throughout the distribution system. Valves and meters and other appurtenances shall be installed throughout the distribution system as control devices and for water audit. Emphasis should be given to operate the systems on automation mode,” the draft reads.
- The document also states that the concept of district metering area (DMA) should be adopted where possible. DMA is a concept for controlling leakages in the water network, which is essentially divided into a number of sectors, called the DMAs, and where flow meters are installed to detect leaks.
- “The water supplier/utility may provide bulk water meters in the water distribution system to ensure water audit, however the provisions should be made for domestic meters also. The water supplier/utility shall ensure that the consumers do not have direct access to the meters to avoid possible tampering of the meters. Provision should also be made to have automatic meters at household level which shall support in water audit,” the document reads.
- The draft also mentions that water should be sampled at the treatment plant every four hours against quality parameters. In the distribution system, the sampling should be done every eight hours at the water reservoirs.
- Random sampling should also be done at household levels.