At the time when gap between theory and practice seems to widen, if focused efforts are put together by creating a space for interaction between citizens and the government an effective outcome is never far. With this in mind, a citizen dialogue was arranged with KSPCB chairman and officials from KSPCB on a concerted issue of reusing excess treated wastewater.
Recent times Bengaluru has witnessed many of the big lakes turning into sewage pools, while a considerable number of lakes have turned to dry bed. Moreover, the Sarjapur-Bellandur area watershed boundary is dependent entirely on groundwater with hardly any recharge. Thus, continuous extraction of groundwater from deep aquifers, little or no recharge, blockages in the stormwater canals have all contributed to the lakes drying up.
Additionally, in areas with no underground drainage system, KSPCB has established zero discharge norms which applies to this watershed as well. It implies that sewage generated in the campus (of apartment, layout, institutions) should be re-used within the campus itself. However, even after using the treated water for gardening, flushing, there is still a significant amount of excess treated wastewater available.
Owing to the issues of depleting groundwater levels, lakes turning into sewage pools and some drying up, solutions like disposing excess treated water into lakes, using excess treated water for recharging shallow aquifers, and for other purposes like construction, etc. started taking place within the community.
This meeting, a dialogue with KSPCB was thus, with an intent of reviewing possible solutions for reusing excess treated water, understanding the challenges and responsibility of everyone in the process of reuse.
The meeting started with an introduction from BIOME on the facts, assumptions about the watershed area of 33 sq. km:
Highlights of the presentation:
1. Sarjapur-bellandur watershed is of 8000 acres
2. Total water spread area 428 acre totaling 15 lakes(excluding Bellandur lake of 892 acre.)
3. Total holding capacity 1731 million liter assuming 1 meter average depth.
4. Evaporation loss: 2597 million liter annually, Percolation estimated: 6231 million liter annually.
5. The capacity of total STPs in the area is approximately 8.5 million liter per day based on the information collected from KSCPCB regional offices.
The KSPCB Chairman Dr. Vaman Acharya, kick started the meeting saying, “If the question is whether the excess treated STP water can be discharged to lakes, given it abides the quality norm? the answer is YES. Because the secret of getting ahead is, getting started”.
The larger questions raised by the residents:
1. If I do have an STP, but no dual plumbing to use it for flushing what do I do with the excess treated water ? As lakes in the city are dry, isn’t it a good idea to let in treated STP water into lakes – to have a perennial source of water? What do the discharge norms really mean? Where do I discharge this treated water? It seems like a shame to put it back into sewer lines to mix this with other raw sewerage and that too for a price!(@Rs 100/- per month per home) when I have spent significant time and money to treat the water - in the first place.
2. I have an STP and dual plumbing. I am using the water for gardening and flushing. I still have excess treated water. I am told that I should not discharge any treated waste water outside my campus. What do I do? If I am sending water outside my campus am I breaking the law?
3. I know my treated water quality is good. Is it ok to let it into the shallow wells for shallow aquifer recharge?
4. It is possible to reuse the treated water for construction purpose?
The challenges that need to be addressed:
- How to maintain the quality of water?
- Who would be held responsible while ensuring the water quality?
- The efficiency, scientific validation and economic viability of the chosen solution.
- Legal Dos and Don’ts
Proposed recommendation on experimental basis:
After a thorough discussion between chairman, and participants below propositions evolved:
- Make a separate outlet/piping to bring the treated water directly to lake.
- Land use application norms would be applicable for comparing the treated water quality for letting into lake or into shallow recharge wells
- Setting up small unit treatment plant at the inlet of the lakes on lake bed (probably in the buffer zone) to ensure control on water quality.
- If the residents are sure of the quality with evidence and directing to lake is not a viable option (far off from the lake) then they may let it to shallow recharge wells.
- For areas with BWSSB connection and underground drainage network: Apartments/ layouts with in-house STP can allow the treated water into nearby lake
- For every initiative to do the above form a group of 5 individual (+/-1) from each authorities: Member of citizen's group, personnel from pollution control board, NGO, lake development authority/BWSSB/BBMP. To have the water quality tested weekly to see the persistent goodness level.
Go Ahead, Conditions applied!!
It has been advised and seeded to all the participants to come up with concrete proposals based on the alternatives proposed in the meeting.
The following data would have to go into the proposal
- Name of the apartment, number of flats/houses, STP capacity, daily treated volume, approximately amount of excess treated water generated daily
- The group that is willing to take responsibility for the lake/process
- Preferred way of disposal: Lake/recharge wells
- Current Depth/Volume/Quality/Other Details like distance of lake from the site (approximate) of Lake/Recharge structures
- Volume/Quality of water that is expected to be discharged
- The process of discharge - time of discharge/process for monitoring (what parameters will be tested, by who, at what frequency)
Documents that need to be submitted along with the proposal: CFE/CFO for STPs, water quality reports for the past 3 months at least to check the consistency
Submit the proposals to KSPCB regional office (BIOME would facilitate this) for getting the permissions.
KSPCB would also engage with LDA to discuss the issue along with the citizens as with the new amendment in the Lake development act, LDA would get more authority.
We would like to thank all the participants who attended the meeting and shared their experiences. We hope that the meeting was fruitful for everyone and assure that further steps would be soon initiated.
Dr.Vaman Acharya, Chairman , KSPCB,
Venkatesh Sekar, Senior Environmental officer, KSPCB
Mr. Shivlinge Gowda, Officer in charge-Apartments, KSPCB
And other environmental officers and staff from KSPCB
Engineers from Lake Development Authority,
Apartment representatives and
More pictures can be viewed here: https://plus.google.com/photos/111781758596840598341/albums/6129725615636884465