Watershed Surveys

Watersheds

Watershed Surveys look at the impact that human and natural activities have on the watershed. Watersheds are areas of land that catch rain or snow and then drain into bodies of water such as marshes, wetlands, rivers, streams, lakes, or to underground sources. Howard County lies within the watersheds of the Patapsco and the Patuxent Rivers, which flow toward the Chesapeake Bay. The Patuxent River drains three quarters of the county, while the Patapsco drains the remaining one quarter. To better assess the conditions in the County's streams, the Stormwater Management Division is collecting information on the physical, biological, and chemical conditions of the county's watersheds.

Stream Corridor Assessment

A physical assessment provides information on erosion sites, fish blockages, channelized stream sections, in- or near-stream construction, inadequate stream buffers, exposed or discharging pipes, trash dumping sites, and unusual conditions found in a stream. Information is collected in order to determine the severity of each problem. The Stormwater Management Division, with the assistance of the Department of Natural Resources (DNR) and the Maryland Conservation Corps, has performed Stream Corridor Assessment Surveys in following watersheds:

The Main Patuxent Watershed is located in the western portion of Howard County. This watershed is particularly important because water flowing over this area of land contributes drinking water to the Rocky Gorge and Brighton Dam reservoirs. It is very important that residents in this watershed keep pollutants such as fertilizers and pesticides from entering the water supply.

The Little Patuxent Watershed is located in the central eastern portion of Howard County. The Little Patuxent watershed is currently the most impacted watershed in Howard County due to its high population density. Howard County is currently working on developing strategies that are designed to remediate erosion and lack of tree buffers; the two largest problems within this watershed.

Little Patuxent Stream Corridor Assessment

Appendices

Maps

The Middle Patuxent Watershed is located in the central portion of Howard County. It is the only watershed whose boundaries are completely located within the County.

Middle Patuxent Stream Corridor Assessment

The Patapsco Watershed is located in the northern portion of Howard County. A watershed restoration plan is currently being designed for this watershed.

Patapsco Stream Corridor Assessment

In addition, a more detailed stream corridor assessment was conducted in 2005 in the Patapsco and Deep Run subwatersheds for the Patapsco WRAS.

Deep Run and Patapsco River Stream Corridor Survey

Biological Monitoring Survey

In addition to the physical stream survey, the Stormwater Management Division conducts biological assessments of the streams in Howard County's watersheds. The biological assessment will study the benthic macro invertebrates (bottom dwelling organisms) that live in our streams. Bottom dwelling organisms are a good indicator of water quality and can be used to determine stream health. The surveys use methods similar to those used by the Department of Natural Resources (DNR) in their Maryland Biological Stream Survey (MBSS). Howard County's biological assessments of the entire County are conducted over a course of five years and we are currently in our third round:

First Round

Little Patuxent, Upper and Lower Brighton Dam, and Cattail Creek Watersheds

The Little Patuxent biological assessment assessed the benthic population to be "poor" and the habitat environment to be "nonsupporting." The biological assessment for Upper Brighton Dam found the benthic population to be "fair" and the habitat environment "partially supporting." While the biological assessment for Lower Brighton Dam found the benthic to be "fair" and "non-supporting."

Little Patuxent, Upper and Lower Brighton Dam, and Cattail Creek Watersheds

Appendices

Middle Patuxent Watershed

The biological assessment has found the benthic population to be "fair" and the habitat environment to be "nonsupporting."

Middle Patuxent Watershed

Appendices

Rocky Gorge, Hammond Branch, and Dorsey Run Watersheds

The biological assessment for Rocky Gorge rated the benthic population "fair" and the habitat environment "nonsupporting." While the benthic score for Hammond Branch and Dorsey Run was "poor" and the habitat score was "non-supporting."

Rocky Gorge, Hammond Branch, and Dorsey Run Watersheds

Appendices

Patapsco Watersheds

The biological assessment for the Patapsco Watersheds rated the benthic population "poor" and the habitat environment "partially supporting." (Note: The Patapsco biomonitoring report includes a comparison summary of the watersheds surveyed in the first round biomonitoring program.)

Patapsco Watersheds and Appendices

Second Round

Cattail Creek and Brighton Dam

In 2005, Howard County began its second round of biomonitoring, which was conducted in the Cattail Creek and Brighton Dam watersheds. Click on the link below to view this report and its appendices.

Cattail Creek and Brighton Dam

Appendices

Little Patuxent Watershed

In 2006 the County finished the Little Patuxent Biomonitoring Survey. Click on the link below to view this report and its appendices.

2006 Little Patuxent Biomonitoring Survey

2007 Middle Patuxent Biomonitoring Survey

2008 Patapsco Biomonitoring Survey

2009 Rocky Gorge, Hammond Branch and Dorsey Run Biomonitoring Survey

Third Round

In 2012, Howard County began its second round of biomonitoring, which was conducted in the Cattail Creek and Brighton Dam watersheds. Click on the link below to view this report.

Cattail Creek and Brighton Dam

For more information on the stream surveys conducted by the Stormwater Management Division, please call: Angela Morales at (410) 313-6586.