Modak Sagar is a lake located in Thane district on the Vaitarna River. It has an overflow level of 163.15 meters, making it the second largest of the lakes supplying water to the city of Mumbai.
The Dam premises are protected by the state government. Access is only for officials from the BMC, however if you wish to see the dam you need to take permission from their head office at VT(now CST). 
The lake is home to crocodiles that inhabit the shallow waters near its coast