Here's how Bengaluru can look beyond Cauvery for water
http://www.newindianexpress.com/cities/bengaluru/Heres-how-Bengaluru-can-look-beyond-Cauvery-for-water/2016/09/17/article3622989.ece1
BENGALURU: Bengaluru is once again facing the prospect of shortage of drinking water, highlighting our heavy dependence on Cauvery river water for drinking. Amidst the emotional scenes witnessed over the past few days over sharing of Cauvery waters, is our own unwillingness to adopt even minimal measures to conserve and recycle water.
At present, Bengaluru requires 1,450 million litres per day (mld) and about 19 tmcft of water per year from Cauvery alone. As population expands, it is difficult to sustain drinking water supply to the city, which is already facing a shortfall.
It is estimated that Bengaluru has the potential to harness 22 tmcft per year from its sewage and storm water drains. Every water conservation technique that is implemented can cut down the use of piped water considerably.
“Any city, in the future, cannot depend on rivers or dams alone for water supply. There has to be better planning. About 50 per cent of it can come from dams and rivers, 20 per cent from rain water harvesting (RWH), 20 per cent from recharged borewells and 10 per cent should be recycled water. This is the only way we can sustain our supply,” says A R Shivakumar, a scientist at the Karnataka State council for Science and Technology at the Indian Institute of Science.
Despite Bangalore Water Supply and Sewerage Board (BWSSB) making it mandatory for building constructed in 30x40ft and bigger dimension sites to have RWH mechanisms, there are only a few takers. Also, there has been no punitive action against those who have failed to implement it.
Shivakumar says that around 1,00,000 homes in Bengaluru have adopted RWH. “It is not a big number compared to more than 20 lakh properties in Bengaluru. But it is a good effort and hopefully will catch on,” he said.
Water recycling in bigger complexes is now catching up in new buildings, but the old ones are hesitant. Recycled water can be used for secondary purposes like gardens, construction and washing vehicles. “A place like Cubbon Park has a state-of-the-art recycling plant and the water is used for gardens. The results are there for all to see. It will not hurt the government to set up treatment plants to recycle the waste generated around its office buildings like M S Building and Vidhana Soudha. This sets a good example and will encourage people to follow suit,” Shivakumar said.
He also blames the unaccounted water that comes via pipelines and then just disappears. According to BWSSB’s own admission, these losses are between 40-45 per cent. “Norms specify that these losses should be around 15 per cent. But, despite the civic agency’s best efforts, these levels have not fallen to below 40 per cent,” says former Chief Secretary A Ravindra.
He also said that protection of groundwater resources is one of the major tasks to be undertaken to improve the situation in the city.
“RWH needs more compliance. The government can also encourage people by constructing large ponds to collect rainwater. Restoration of tanks and lakes and groundwater recharging can help meet the drinking needs of the population to a large extent,” he adds.
Message on BWSSB website
A message on BWSSB website reads: “Since there have been drought conditions prevailing in Cauvery basin which have resulted in minimal flow into the reservoirs in the month of August and September, enough Cauvery water may not be available in the coming months. As the rainfall prediction is meager, the BWSSB requests all its consumers to consume and use water judiciously.”
5 ways to save water
Water conservation experts say that by following these simple steps, the city can save a lot of water over time
Rainwater Harvesting
It could be as simple as placing a bucket below the pipe that channels the rainwater in your house, but BWSSB rules make it a little more comprehensive and mandatory. It is the simplest and most essential form of conservation residents can adopt and works on the premise that there should be 20 litres or more tank capacity per square metre of roof area. Unfortunately, at present, there are only an estimated 1 lakh homes which have implemented this but wider application can easily solve our water woes. We can save around 23 tmcft per year this way.
Recharging lakes and groundwater
Recharging lakes is a crucial component of ensuring self-reliance in terms of water supply. Not only do we manage to fill our lakes, but we can also recharge the groundwater and aquifers. However, the city’s lakes are composed of silt consisting of sewage, waste chemicals, organic waste, dead vegetation and heavy metals turning the bottom of the lake into a cement-like impermeable layer. Even if the water permeates, it will poison the underground water table. Stopping sewage inflow into lakes and clearing out catchment areas is very essential.
Sewage Treatment Plants
Almost every lake in the city has copious amounts of sewage flowing into them, turning them into a frothy nightmare. Not only are STPs necessary to stop this, they can be adopted on a smaller scale in apartments, commercial and government buildings. Even if people are not comfortable using this recycled water for domestic purposes, there are plenty of uses like watering gardens, washing vehicles and reusing them for flushing toilets.
Unaccounted losses
According to BWSSB, around 40-45 per cent of the Cauvery water is lost and pegged as ‘unaccountable losses’. That is around 650 mld. The water lost due to leakage in pipes is negligible. Most of this water is pilfered, which means illegal water connections are drawn right from localities to large industries and hotels. Efforts to control this form of losses are lukewarm. Politicians do not want to upset their vote banks and only strong political will can bring this under control.
Tariffs and incentives
At the lowest slab, water supply from BWSSB means that a house gets 1,000 litres of water for a measly `8. The higher slabs are not much of a deterrent either. An expert on water conservation techniques says that the government should take the bold step of providing around 10,000 litres per month (going by WHO’s recommendation of 100 litres/person/day) at a low rate and then hike the tariffs exorbitantly. That would make everyone sit up and take notice and consequently choose water conservation methods to avoid paying a higher tariff.
