• Stream Conditions
• Wetland Acres
  

Stream Conditions

Healthy and diverse aquatic biological communities, along with high quality in-stream and riparian habitat, are indicators of the condition of our streams and watersheds. The biological community living in a stream reflects the cumulative impacts of human activities and landscape processes in the watershed.  In 1998, the Countywide Stream Protection Strategy (CSPS) was published. This document uses information about the fish and aquatic macroinvertebrate communities as indicators of the condition of county streams. The CSPS provides stream condition maps for over 22 county watersheds as well as detailed habitat information. Table 1 summarizes stream conditions throughout the County. By the end of 2000, DEP will revise the CSPS, providing needed stream condition data for the 11% of the stream miles that had no available data in 1998. New stream condition maps will also be prepared for many of the county watersheds using monitoring data collected since 1998. All revised maps and information will be able to be downloaded from our web site.

A decline in the condition of our streams results in a reduction in biodiversity within our landscape, as more diverse fish and insect communities are reduced to a community with mostly pollutant and stress tolerant species. A decline in stream condition also generally reflects an increase in human induced impacts in a watershed that are not being adequately managed, such as increases in stormwater runoff, stream erosion and sedimentation, warming of stream temperatures from paved areas and inadequate forested buffers, pollutant loads and trash dumping. These watershed impacts reduce the aesthetic and recreational value of our natural resources, and contribute to the degradation of downstream resources such as the Potomac River and Chesapeake Bay, resulting in costly efforts to restore ecosystems and protect structural and non-structural economic goods, such as bridges, culverts, trails and fisheries.  Reduced stream quality, manifested in increased sediment, nutrient, or other pollutant loadings, also impacts water supply reservoirs and treatment costs of water withdrawn from other watersheds to support public water supply needs.

Table 1.  1998 Countywide Assessment of Stream Conditions

Water Quality: Wetland Acres

The existence of a well balanced non-tidal wetland complex is a sign of a healthy water flow ecosystem. Non-tidal wetlands help water systems to absorb stormwater during flood events, remove nutrients, sediments,and other pollutants from the water, and provide unique habitat for plants and animals which depend upon these areas, including many rare species of reptiles and amphibians.

Non-tidal wetlands are lost due to land development, highway building, and other projects that directly impact waterways. Indirect impacts also occur when upland and nearby development redirects drainage patterns, increases surface runoff, and reduces groundwater inflows to negatively impact the hydrologic regime critical to a viable wetland environment. When surface runoff and groundwater flows to wetlands are substantially altered, many vital wetland functions can be lost.

The County wetland table provides information about the amount of wetlands in Montgomery County and shows the four major wetland types; there are 79 different types (major = highest acreage totals) and a fifth category that sums the remaining wetland types.