Perieri Lake Restoration

Ecology classes with PFC started up. Grade 7 is going through the Year 2 of the program. This year the focus will be to study human-environment impact in local areas and the work being done to minimize the damage.  The year started up with a visit to see the lake restoration work being done by PFC in Siruseri, in conjunction with TCS & IIT-Madras.  Here is a account written by the children after the trip:

Periari Lake, in Siruseri is being restored. The 100 acre lake which is actually an Eri, used to be used by the Siruseri locals. Till big buildings came up, it was unpolluted. There are actually two Eries connected by a waterway, next to each other, but when the big buildings  built, there were built on the waterway. 

When the floods came in 2015, the lake/Erie filled with water from other Eries and it started flowing through the waterway. The buildings go flooded because it was on the way to the other Erie. The buildings were damaged. Another outlet for the water was near the Siruseri village so they got flooded too.

Then the lake dried up.

What is restoration?

Restoration basically means getting something to what it actually was. In ecological restoration, the ecosystem is restored to its original status before human impact.

Who is involved in this?
The Pitchandikulum Forest Consultant team planned the lake to be ecologically restored. The Civil Engineering department from IIT Madras designed it. TCS is investing in it. The most important people are the Siruseri people themselves. They are the ones living there and know more about the Eri than anyone else.

Why is it getting restored?

This particular Eri, Perieri, is a water supplier to 1/4^th of Chennai. This comes in the Pallikarnai watershed. This eri used to be surrounded with agricultural lands and forests. But now there are only apartments and IT offices. The eri has dried up. The ecosystem there is ruined.

When agricultural lands were there, the eri was used for so many things:

·         Drinking water

·         Preventing landfills

·         Baths

·         Washing clothes

·         Wildlife

·         Swimming

·         Fishing

A respondent to the PFC survey among the locals who used to live near the Eri, said, “We used to swim there, but now our grandchildren don’t have a chance.”

 

How it is being restored

While restoring a lake, you clean it up and make it a sustainable home for organisms like fish, birds, and land organisms which live nearby. You can make islands and hills and plant with trees so birds can nest.  When water is there, algae come. If algae are there, fish come. If fish are there, birds come. If birds are there, land animals will come.

The eri is being desilted. Desilting is where you remove the sand from down which accumulates so that the lake doesn’t turn into a marshland.  The clay mud is being dug out and used to make 3 big hills – which are watchouts for the public on the side. 2-3 islands are being built for birds, plants etc.

The spillway, which is where the water exits the eri. Siruseri was flooded in the 2015 floods because, the eri was full and the spillway was towards the village.  During the restoration, the spillway is being moved.

 

The restoration will help not only wildlife and the earth, but the people living there too. There is so much waste that it just ends up in the landfills in todays world. But in the olden days, there used to be circular movement. Organic waste was thrown into the eri, the fishes would eat it and so on. The Eri restoration is going to help the circular movement come back and for wildlife preservation.  

By Shahana Shameer, Abdullah Ibrahim, Safwan Samsudeen Grade 7