Intro: What is a water basin? How does it affect you and your family or business?

A basin is a depression, or dip, in the Earth’s surface. Basins are shaped like bowls, with sides higher than the bottom. Some are filled with water. Others are empty.

Basins are formed by forces above the ground (like erosion) or below the ground (like earthquakes). They can be created over thousands of years or almost overnight.

Every town in Connecticut is part of a water basin (or two, or three). Water in a basin consists of many things like water in a lake or river, rainfall, groundwater, wastewater discharges to underground or surface water, and even water from onsite treatment systems (e.g. septic systems).

With a finite amount of water in a basin, it's important to manage it properly to ensure streams and wells don't run dry.


major water basins

Connecticut has eight major watershed basins:

1. Pawcatuck
2. Southeast Coast
3. Thames
4. Connecticut
5. South Central Coast
6. Housatonic
7. Southwest Coast
8. Hudson

Within these major basins are 44 regional basins, detailed maps below.

What is your basin?

Don't know the name of your basin?

Find your town and corresponding basin/s in the table below, then use the regional basin links to see the basin summary for the water in your area.

Find your town below to see what basin(s) it is in. Click the basin name above to see its basin summary from the Water Plan