> ROUTINE FIXED-SITE NETWORK

> BED SEDIMENT AND FISH TISSUE STUDY

> MERCURY IN WATER, SEDIMENT, AND FISH

> URBAN LAND-USE GRADIENT STUDY

> NUTRIENT-CHLOROPHYLL STUDY

Overview

Surface water studies of the NAWQA Program use three interrelated components — water column studies, streambed sediment and fish tissue studies, and ecological studies — to assess the quality of important streams in a study unit. These study components rely on both routine or repetitive monitoring at similar sites over a period of years and limited time (termed "synoptic") sampling. Monitoring is conducted at streams that represent major rivers or hydrologic areas, important environmental settings and land uses, and for characterizing specific water-quality issues. For more information on the design of the National Program, go to the section Design Components in "What is NAWQA?"

Rivers of the New England Coastal Basins Study Unit

The NECB study unit contains a number of major coastal drainages in eastern New England. The largest river basins in the NECB study unit are the Kennebec (drainage area of 5,890 mi²), Merrimack (5,010 mi²), Androscoggin (3,520 mi²), and Saco Rivers (1,700 mi²). Important, but smaller, coastal drainages include the Charles (321 mi²), Blackstone (335 mi²), and Taunton Rivers (530 mi²). These rivers and their drainages are used extensively for drinking water, industry, power generation, wastewater discharges, and recreation.

Determining the effects of new and old urbanization on the quality of streams in the NECB study unit was a primary design feature for the surface-water studies. To assist in understanding the effects of urbanization, natural variability in stream quality was minimized by focusing, to a large extent, on streams in the Northeastern Coastal Zone ecoregion as defined by Omernik (1987) and revised in 1999.

Five surface-water studies were conducted as part of the NECB study from 1998 through 2001:

• Routine fixed-site monitoring for water chemistry and ecological assessments
• Occurrence survey of trace elements and organic compounds in streambed sediment and fish tissue
• Presence of mercury in water, sediment, and fish tissue
• Urban land-use gradient study
• Relations between nutrients and chlorophyll