Image credit: John Stetson
Featured Lake
Sebago Lake
About Sebago Lake
- Sebago Lake is located in the towns of Casco, Naples, Raymond, Sebago, Standish and Windham. It is the deepest and second-largest lake in Maine at 96.3 meters (316 feet) and 12,137 hectares (29,992 acres), respectively. The perimeter of Sebago -- 158 kilometers (98.2 miles) -- is substantially developed and about 90% of the watershed is privately owned. Despite this, significant eutrophication (caused primarily by phosphorus runoff) has been limited. This is vitally important as it is the primary water supply for the Portland Water District (PWD) which serves nearly 15% of Maine’s population. The reason for the limited eutrophication is due to the large and heavily-forested nature of the watershed and the fantastic work of PWD, Sebago Clean Waters, and many lake stewards. Two other factors that may play a role are that areas of its watershed -- notably the Long Lake region -- are naturally high in aluminum and are at greater elevation. Generally, higher elevations have less marine-derived clay soils which are typically high in phosphorus. A last note, the oldest recorded ice-out, taken in 1807 CE, comes from Sebago.
What's New?
A Half-Century of Maine Lakes Data!
Last year, Scott Williams (long-time LSM Executive Director) wrote a short article about the early years of VLMP and the treasure trove of Secchi data produced by volunteers.
As we close out the 51st year of VLMP/LSM, it is worth taking another look at some stats on the lake water quality data collected over the years. Here are some tallies *:
- Secchi: 141,141 measurements from 1,066 lakes
- Phosphorus: 67,402 measurements from 936 lakes
- Temp/DO: 42,633 profiles from 944 lakes
- pH: 38,442 measurements from 874 lakes
- Conductivity: 31,733 measurements from 891 lakes
- Chlorophyll: 25,006 measurements from 908 lakes
- Color: 24,929 measurements from 910 lakes
- Alkalinity: 20,093 measurements from 887 lakes
Here are 3 interactive visualizations exploring these data:
(* These totals refer to data through 2018; as of the end of 2022, DEP had not released the more recent data for upload to this website. Totals include data from all lake stations and dates.)
Click here for previous What's New stories
Did You Know?
Maine Ice Data
Did you know that you can participate in collecting community science data? Lake Stewards of Maine tracks ice-in and ice-out on lakes throughout the state. This does not require special equipment or certification, just your time, thoughtfulness, and willingness to help! To get involved you can go to Lake Stewards of Maine’s Ice Data Page and read more about the program.
Sebago 5786 Photo by Claudia & Phil Lowe
Lake Stewards of Maine monitors, ice-in (the time when ice covers the lake surface), partial ice cover (a transitory stage on the lake, either ice has melted on a warm winter day or ice has developed on an especially cold autumn or spring day), and ice-out (when ice no longer covers ~90% of the lake, or is insubstantial). Click here to see the data collected this year. To see historical ice data please contact stewards@lakestewardsme.org.
Submit data here and thank you!
Click here for previous Did You Know? stories
Current Conditions
Click here to view current water quality conditions on a representative sample of Maine lakes during summer, or view which lakes have experienced ice-cover in the fall and ice-out in the spring.
Get Involved
The majority of data on lakesofmaine.org comes from certified volunteer citizen scientists. If you are interested in finding a monitoring opportunity, please visit Lake Stewards of Maine or contact our office at 207-783-7733. Email is stewards@LakeStewardsME.org
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