Teacher's Colony Kulam
Teachers Colony Kulam has been chosen for restoration by CMWSSB as part of the Sustainable Water Mission.It is located in Teachers Colony, 4th Main Road at Tiruneermalai. Now the pond is fully restored under the Chennai Smart City project funds.
Area, Zone, Division
AREA :2428.116 Sq.mtrs. , ZONE : 3, Division : 32
This pond is located in Division 32 of Zone – 3 and is on the Teachers Colony 4th Main Road. The pond is located at North Latitude 13° 7'47.12" and East Longitude 80°12'13.28".
Field Observation and Inferences
The pond is rectangular in shape. There is water in the pond during the time of survey. The bund in the pond is not provided with revetment. There is an openwell inside the pond was used as part of panchayat water supply in the past. At present the well is not in use. It is filled with waste water being diverted from the neighbouring houses. A storm water drain that is diverted to the pond, carries sullage water, polluting the pond. It is also dumped with solid waste extensively. The pond is covered on all sides with compound wall of the residences and hence it does not requires a compound wall. There are two gates provided to the pond one each in Western and Eastern side. At present, there is no specific catchment to the pond but for its own in-situ catchment. Based on the interaction with the community, it is inferred that the pond water got polluted due to sullage diversion which inturn has also polluted the groundwater that is tapped through openwells in the neighbourhoods.
Based on the Total Station Survey output, it is inferred that the total area of the pond is 2,401.2356 sq.m and the total length of the bund is 196.669m. The average depth of the pond is about 2m.
Impact of Urbanisation
The imagery extracted from google earth on 21.03.2016 and 26.06.2010 is presented below shows no major change on the water spread area of the pond. But the impact of urbanisation is reflected in rampant domestic sullage diversion and solid waste dumping in the pond.
Google Image of the pond as on 21.03.2016 (LEFT) and 26.06.2010 (RIGHT)
Pond Storage Estimation
The actual volume stored in the tank during 1987 – a normal rainfall year - after losses due to evaporation and recharge is given in the following graph
The total storage of the tank in its present condition is estimated at 3481.798 cu.m Based on this estimate, there will be water available in the pond for almost 119 days in a year. At no point of time, the pond overflows in a normal rainfall year. The total inflow to the tank in a normal rainfall year is estimated at 3778.25 cu.m; the total groundwater recharge will be 2661.67 cu.m. The estimate was made in an excess rainfall year to see the inflow and outflow status. The actual volume stored in the tank after losses due to evaporation and recharge is given in the following graph.
Based on this estimate, there will be water available in the pond for 268 days. The pond in its present volume does not over flows even in an excess rainfall period for the assumed catchment. The total inflow to the tank in an excess normal rainfall year is estimated at 6048.50 cu.m; the total groundwater recharge is 2080.3 cu.m.
Based on the field observations and inferences, followed by the data analysis, following were the list of activities proposed for renovating the pond.
To start with, the sullage diversion into the pond should be stopped. As the sewage line (UGD) has already been laid, it would be an easy task to check and divert the sullage flow from the inlet channel. The outfalls from the individual houses should be stopped by providing soak pits at the house hold level.
The existing water should be dewatered and disposed.
The pond should be desilted and water hyacinth removed.
The bushes all around the bund should be removed and the bund strengthened; as the pond is fully fenced with two gates, it does not require neither fencing nor gate.
Dumping of solid waste should be stopped.
The roof top pipes from the surrounding houses can be diverted into the pond.
After completing the above tasks it is better to retain the water body as such for 1 – 2years after which the water body can be converted into a surface run off water harvesting and recharge system. Introducing recharge system at this stage would lead to the pollution of groundwater and hence it is not recommended.