Safe Beaches

We are seeking volunteers to help us monitor the Lowell and Lawrence beach houses for the 2012 season!

If interested, please contact MRWC at 978-655-4742 or email us at

Please click here to learn more about the Safe Beaches Project, or here for historical data from the 2011 and 2010 seasons.

Water quality data are collected for the Merrimack River Safe Beaches Project in Lowell and Lawrence. Flags indicating water quality are posted at the Lowell Heritage State Park Beach, UMass Lowell Bellegarde Boathouse and Abe Bashara Boathouse at Riverfront State Park in Lawrence.

Water quality advisories are based on E. coli bacteria (Escherichia coli) counts. Results from these samples are available approximately 24 hours after samples are taken.

Other data, including water temperature, conductivity, total dissolved solids, salinity, dissolved oxygen, pH, ammonium, ammonia, nitrate, turbidity, chloride, and recent precipitation, are also collected. In the future, we plan to use these additional data to generate a model that will enable us to predict water quality. This model may allow us to collect fewer parameters and then predict bacteria levels, thereby allowing a timely posting of water quality.

What it Means for You:

Good water quality, signaled with a Blue Flag, is determined by low bacteria counts, less than 126 colony forming units (cfu) per 100 mL.  Contact with the water from boating or swimming is not likely to cause illness.
Questionable water quality, signaled with a Yellow Flag is determined by moderate bacteria counts, between 126 and 235 cfu/100mL.  Contact with the water may cause illness.  Swimmers and boaters should be cautious and wash after contact with the water.
Poor water quality, signaled with a Red Flag, is determined by high bacteria counts, above 235 cfu/100mL.  Contact with the water may cause illness.  Swimming is not advised on days with poor water quality.  Boaters should be cautious and wash after contact with the water.