Landowners along the Lamprey responding to the LRAC’s landowners’ survey identified water quality as the single most important attribute to protect on the river. Because of its clean water, the river now supports a healthy diversity of aquatic life, provides public drinking water (after treatment), and supports swimming, fishing, boating, and other water-based recreation.
The Lamprey is legislatively classified as a Class B (swimmable, fishable) river, and is thus managed by the State under the federal Clean Water Act to maintain “fishable and swimmable” conditions. Water quality in the LRAC study area is generally high. During the summer, however, because it is warm, slow moving, characterized by low flows, and has several ponded areas, the river is vulnerable to pollution. Water quality occasionally suffers from excessive algae growth from nutrients entering the water, and dissolved oxygen and bacteria levels occasionally fall short of standards for a Class B river. During periods of extreme low flow, copper and zinc concentrations also occasionally have reached levels considered harmful to aquatic life. (For a summary of water quality data see the Resource Assessment and Lamprey River Water Quality Report for the Nonpoint Source Program, 1994, prepared by the NH Department of Environmental Services.)
Pollution problems are categorized in general terms as either originating from “point” sources or “nonpoint” sources. Point sources are discharges from pipes, such as pipes leading from sewage treatment plants, industrial plants, and stormwater culverts. A nonpoint source is any site from which polluted runoff can occur, such as a construction site, a pasture, or a heavily fertilized lawn. Difficult to locate and correct, nonpoint pollution currently is recognized as the greatest problem in maintaining high water quality nationally and locally.
The Clean Water Act of 1972 focused on the clean-up of point source pollution. Its initial success revealed the importance of addressing the additional impacts of nonpoint source pollution on rivers and lakes. Today, pollution prevention must also focus on appropriate stormwater, septic system, and land management practices by public and private landowners. Maintaining buffer areas of natural vegetation along the river may be the most single important means of preventing nonpoint source pollution from reaching the river. Both enforcement of local and state regulations and the cooperation of informed landowners are needed to deal effectively with this issue.