Officials from Westport, Fairfield and Easton gathered Friday at Southport Beach to hail the signing of a regional conservation plan for the Sasco Brook watershed.

Created by the volunteer Sasco Brook Pollution Abatement Committee, the "Watershed Vision Management Plan for the Sasco Brook Watershed" outlines 10 objectives that focus on protecting and improving surface water quality by reducing runoff pollution in the 10-square-mile watershed -- encompassing parts of Westport, Fairfield and Easton. Westport's Board of Selectmen last week approved a memorandum of agreement that endorsed the new watercourse protection.

"My vision is -- it's more like a prayer -- that maybe in the future we won't need a plan," said Westport Conservation Director Alicia Mozian. "It'll just become part of people's mindsets and behavior that they connect themselves to the environment and that they are naturally good stewards of the land."

The Watershed Vision was developed as part of the Sasco Brook Watershed-Based Plan, which was produced by the committee in 2011.

The Sasco Brook plan recommends initiatives to reduce runoff pollution, which occurs when water picks up contaminants as it runs off roads, parking lots, driveways, lawns and other surfaces. That runoff is occasionally carried by stormwater into the brook, its tributaries and eventually into Long Island Sound.

Poorly functioning septic systems that leak bacteria, fertilizer nutrients and bacteria from animal waste also produce runoff pollution. To better understand the impact of those sources, the Sasco Brook Pollution Abatement Committee hopes to launch later this year a federally funded study that would include DNA analysis of bacteria sources in the watershed.

"The connection between watersheds and water bodies is critical," said Mark Tedesco, director of the Long Island Sound Study, an initiative that aims to restore and protect the Sound and includes the Environmental Protection Agency and state agencies from Connecticut and New York. "The work that you're doing in thinking about the quality of your local watersheds is going to make a difference in terms of the quality of Long Island Sound."

Officials noted that local conservation initiatives have already improved the brook's water quality compared to its condition in the early 1990s when the Pollution Abatement Committee was established. While shellfish beds at the mouth of the brook at Southport Beach are still closed, the brook is open for fishing and may eventually be swimmable.

Shellfish, nonetheless, live in the brook and can be transferred for harvesting farther south into other parts of Long Island Sound, said Kristin DeRosia-Banick, an environmental analyst at the state Department of Agriculture's Bureau of Aquaculture and Laboratory. They cannot be harvested in the brook, however, because they absorb high levels of bacteria.

De Rosia-Banick did not rule, though, the Bureau of Aquaculture eventually re-opening of the shellfish beds in the brook.

"Some incredible changes have been made over the last 10 years," she said. "We take samples year-round under all conditions and we re-evaluate those every year. If we need to make classification changes, we can do that."

About 20 percent of the watershed lies in Westport, about 80 percent is within Fairfield and a small part is in Easton.

"Easton has dedicated itself as a community to the protection of the watershed," said Easton First Selectman Thomas Herrmann. "The protection of the watershed, the watercourses and the water supply is what we see as our purpose and our mission for this region."

The Sasco Brook Pollution Abatement Committee includes Mozian and other representatives from municipal, state and federal government agencies, as well as private citizens.

Among a variety of roles, the committee advises local land-use boards when they review cases affecting water quality and natural habitats in the watershed.

pschott@bcnnew.com; 203-255-4561, ext. 118; twitter.com/paulschott