Anywhere shellfish are harvested, Maine’s Department of Marine Resources regularly tests bacterial levels to make sure the shellfish are safe for eating. While it’s critical to determine whether bacterial contamination is present, this sampling is limited to certain areas, and may not provide information about the source of any contamination.

A new water quality lab at Damariscotta River Association (DRA), however, will make it much easier and less expensive to analyze water samples from any location. The lab procedure measures a particular type of bacteria called Enterococci with a high level of precision at a low cost.

Enterococci are bacteria originating in the guts of all warm-blooded animals. It is common to find low levels in the river and its tributaries. However, if high levels are found, it can be an indicator of bacterial pollution and diseases associated with sewage.

The water quality lab will be especially valuable in pinpointing sources of bacterial contamination. If a shellfish harvesting area is closed due to contamination, for example, the local shellfish commission can move ahead with targeted water sampling in the immediate area and have its samples tested in the new lab.

Groups can either process samples themselves or have DRA staff do it for them. DRA can also provide technical support with how to manage the data and what to do with the resulting information.

Using a traditional method of analysis, samples are incubated in an open dish, and analysts look at the samples under a microscope and count colonies of bacteria. This method is time-consuming, results are variable, and lab technicians risk exposure to bacterial contamination.

The test procedure in DRA’s lab, by contrast, is simpler, faster, and safer. Media, or food for bacteria, is added to a water sample. This media will make any bacteria fluoresce, or glow, under ultraviolet light. The sample is poured into a well and sealed. The sealed well is incubated for up to 28 hours to give bacteria time to feed and grow. When the sample is then examined under ultraviolet light, any wells containing elevated levels of bacteria will glow bright blue.

The lab equipment includes sample trays, a sealing device, an incubator, and an optical reader. Purchase was made possible by a small seed grant from Sustainable Ecological Aquaculture Network (SEANET), along with support from DRA membership.

The new water quality lab at DRA is already in use, with Lincoln Academy students the primary technicians. Not only are the students benefitting from lab experience, but they are also able to gaining an understanding of the direct relationship between activities on land and water quality.

With the lab, DRA hopes to learn more about the Damariscotta River and its tributaries. This understanding will in turn guide land conservation efforts.

For more information call 207-563-1393, email dra@damariscottariver.org, or visit the website at www.damariscottariver.org.