WATER QUALITY SUMMARY

BAUNEG BEG Lake, North Berwick (York County)

MIDAS: 3992, Sample Station # 1

Introduction: The Maine Department of Environmental Protection (Maine DEP) and the Volunteer Lake Monitoring Program (Maine VLMP) have collaborated in the collection of lake data to evaluate water quality, track algal blooms, and determine historical water quality trends. This dataset does not include bacteria, mercury, or nutrients other than total phosphorus (TP).

Water quality monitoring datasets for Bauneg Beg Lake have been collected since 1975. During this period, 8 years of basic chemical information was collected along with 18 years of Secchi disk transparency (SDT) measures. In summary, the water quality of Bauneg Beg Lake is considered below average based on measures of SDT, total phosphorus and chlorophyll-a (Chla). The potential for nuisance summertime algal blooms on Bauneg Beg Lake is high.

Water quality measures: Bauneg Beg Lake is a colored lake (average color 62 SPU) with an average SDT of 3 meters (9.8 feet). The range of upper water column TP for Bauneg Beg Lake is 13 - 21 parts per billion (ppb) with an average of 17 ppb. Chla ranges from 1.8 - 17.8 ppb with an average of 5.5 ppb. Recent dissolved oxygen (DO) profiles show substantial DO depletion in deep areas of the lake. The potential for phosphorus to leave the bottom sediments and become available to algae in the water column (internal loading) is high.

Comments: The flushing rate of Bauneg Beg Lake (8.8 times per year) is higher than the average flushing rate for Maine lakes. This high flushing rate is due to the Great Works River draining into the lake. Rivers often carry high phosphorus levels, and the Great Works River drains the urbanized area of Sanford, which increases the phosphorus input to Bauneg Beg Lake. The natural color of the water tends to reduce the tendency of the lake to produce high algae growth. However, several blooms have been recorded (1979 and 1988) and the lake shows high phosphorus in its deeper, low oxygen water, making it susceptible to future water quality problems.

See the Maine DEP Explanation of Lake Water Quality Monitoring Report for measured variable explanations. Additional lake information can be obtained by contacting Maine DEP at 207-287-3901 or VLMP at 207-783-7733, and at these Websites: http://www.lakesofmaine.org and http://www.maine.gov/dep/water/lakes/index.html and http://www.mainevolunteerlakemonitors.org .

Filename: BAUN3992.doc, Revised: 12/06, By dbh