Watershed Management
Studies & Assessments

Tiber and Plumtree Watersheds

For more details, please visit our Tiber and Plumtree Watersheds webpage.

Centennial Lake and Wilde Lake Watershed Studies

In 2004 – 2005 the County’s Stormwater Management Division conducted a watershed assessment and developed a watershed restoration plan for the Centennial Lake and Wilde Lake watersheds. Wilde Lake is a 1.9 square mile watershed, which is highly developed and is predominated by low, medium, and high density residential development Centennial Lake is a 3.6 square mile watershed, which is less densely developed and contains mostly low density residential development and low intensity agriculture.

The purpose of the studies was to assess the water quality in the lakes as well as the streams draining to the lakes, and then to propose strategies and projects for the restoration and protection of the lakes and their tributaries.

Two public meetings were held to discuss the findings of the study and to solicit stakeholder input on the assessment and proposed restoration strategies. The results of the studies are contained in the Centennial and Wilde Lake Watershed Restoration Plan (September 1, 2005). The Plan contains specific locations and recommendations for projects and actions that can be taken to improve the health of the lakes and the streams that drain to them. To view the study, click on the links below:

For more information please contact Mark Richmond at 410-313-6413 or msrichmond@howardcountymd.gov

Font Hill Tributary Stream Restoration – Centennial Lane West

Howard County performs watershed restoration projects to help in meeting its National Pollutant Discharge Elimination System (NPDES) permit conditions and Total Maximum Daily Load (TMDL) goals and has selected the Font Hill Tributary Stream Restoration Project as part of its watershed restoration efforts. This tributary was identified in the Little Patuxent Watershed Study completed in February 2016. The project limits consist of the existing stream starting approximately 6,000 linear feet upstream from Centennial Lane to the downstream limit at Centennial Lane. The proposed project limits are completely contained within Howard County owned open space. This project is being completed by a design/build team comprised of Johnson, Mirmiran and Thompson, Inc. and Environmental Quality Resources, LLC. The document links below were presented at the initial project public meeting on November 30, 2017. The Font Hill Tributary Stream Restoration Project Construction Phase is anticipated to begin Fall 2018 and continue through to the beginning of Fall 2020.

Font Hill Presentation
Location Map
Meeting Agenda and Stream Restoration FAQ

Little Patuxent and Middle Patuxent Watershed Assessment

The Howard County Department of Public Works has undertaken a comprehensive watershed assessment within the Middle Patuxent River and the Little Patuxent River watersheds. The watershed assessment was performed to create an inventory of the natural resources as well as existing problems (erosion, trash, lack of wooded stream buffers, etc.) within these watersheds. Another result of the assessment is a list of potential projects that can be done to protect and restore these resources, address the problems, and ultimately improve water quality in our County streams and water bodies.

This assessment measured current environmental conditions and identified opportunities for restoration projects to be included in the capital budget. These projects will improve water quality in the County’s streams and rivers as well as the Chesapeake Bay. Potential projects investigated include stream restoration, adding water quality treatment to existing stormwater management ponds, constructing new stormwater management facilities, performing reforestation, and stabilizing existing storm drain pipe outfalls.

Due to the large overall study area, the field work was conducted in four distinct areas -- Northern Little Patuxent, Southern Little Patuxent, Northern Middle Patuxent, and Southern Middle Patuxent watersheds as depicted on the Little and Middle Patuxent Watershed Map. The County conducted a public meeting in each of the four study areas to report on the findings of field work results, to describe the next steps in the assessment study, to review possible restoration techniques, and to discuss the status of its countywide plan for meeting Chesapeake Bay Total Maximum Daily Load (TMDL) goals. Crews of two or three County employees or consultants conducted the field assessments, which entailed performing visual observations, taking photos, preparing sketches, and entering the data into handheld field tablets.

The results of the field assessments were used to score and rank the potential project sites, and concept plans were developed for the highest rated 148 sites. A report was generated for both the Little Patuxent and Middle Patuxent watersheds, which includes the study methodology, results, and the concept plans. Some concept plans are on private properties; however, these potential projects will only move forward with the permission of the property owners. These reports are available through the following links:

Little Patuxent Watershed Report
Middle Patuxent Watershed Report

If you have any specific questions or concerns or would like additional information regarding the watershed assessment, please contact the County by emailing Christine Lowe at cslowe@howardcountymd.gov or calling 410-313-6444.

Past meeting presentations:

June 17, 2015 - Southerm Middle Patuxent Watershed
June 22, 2015 - Northern Little Patuxent Watershed
June 24, 2015 - Southern Little Patuxent Watershed
June 30, 2015 - Northern Middle Patuxent Watershed
December 2, 2015 - Northern Middle Patuxent Watershed
December 3, 2015 - Southern Little Patuxent Watershed
December 9, 2015 - Southern Middle Patuxent Watershed
December 10, 2015 - Northern Little Patuxent Watershed

Patapsco and Mainstem Patuxent Watershed Assessment

Having completed the Little Patuxent and Middle Patuxent Watershed Assessment as noted above, the County has begun another watershed study for the remainder of the County. This study includes the Patapsco River and Mainstem of the Patuxent River watersheds. The study purpose and methodology are the same as the Little Patuxent and Middle Patuxent watershed assessment. Due to the large overall study area, the field work is being conducted in five distinct areas – South Branch Patapsco River, Lower North Branch Patapsco River, Brighton Dam/Triadelphia Reservoir, Rocky Gorge Reservoir, and Patuxent River Upper watersheds. Field assessments for this study were completed in April through May 2016.

(Click on the map for a larger image)

The County welcomes public participation in the development of the watershed study. The County conducted public meetings in Summer 2016 and January 2017 to report on the findings of field work results, to describe the next steps in the assessment study, to review possible restoration techniques, and to discuss its countywide plan for meeting local and Chesapeake Bay Total Maximum Daily Load (TMDL) goals.

The results of the field assessments were used to score and rank the potential project sites, and concept plans were developed for the highest rated 180 sites. A report was generated for both the Patuxent River and the Patapsco River watersheds, which includes the study methodology, results, and the concept plans. Some concept plans are on private properties; however, these potential projects will only move forward with the permission of the property owners. These reports are available through the following links:

Patuxent River Watershed Assessment Report
Patapsco River Watershed Assessment Report

 

A public review period for the watershed assessment reports is available until March 1, 2017. If you have any comments on the reports, any specific questions or concerns, or would like additional information regarding the watershed assessment, please contact the County by emailing Christine Lowe at cslowe@howardcountymd.gov or by calling 410-313-6444.

 

Past Meeting Presentations:

June 21, 2016Rocky Gorge Reservoir and Upper Patuxent River Watersheds
June 23, 2016 - Lower North Branch Patapsco River Watershed
June 28, 2016South Branch Patapsco River and Brighton Dam/Triadelphia Reservoir Watersheds
January 23, 2017Brighton Dam/Triadelphia Reservoir, Rocky Gorge Reservoir and Upper Patuxent River Watersheds
January 26, 2017South Branch Patapsco River and Lower North Branch Patapsco River Watersheds
Small-Scale Programs – How You Can Help

Upper Little Patuxent Watershed Management Plan

In 2007, the County's Stormwater Management Division began work on the Upper Little Patuxent River Management Plan. The Upper Little Patuxent River Study area is 17.3 square miles and contains approximately 44 miles of streams. The purpose of the plan is to identify problem areas in the watershed that may affect water quality and to develop a watershed restoration plan to address the problems.

The first of two planned public meetings was held on June 3, 2008, to report on the findings of the County's initial stream corridor assessment, which assesses the conditions of the County's stream. The purpose of the meeting was to discuss what citizens can do to help improve water quality in the watershed and to solicit input. The meeting presentation and maps are available below:


June 2008 Presentation

Upper Little Patuxent Public Meeting Presentation

Stream Corridor Assessment Results

Impervious Cover Maps

Typical Pollutant Loading Model Results Map

The second public meeting was held March 24, 2009 to review the results of the study. Overall watershed recommendations and specific projects were presented at the meeting as were actions that can be implemented to help the health of the Little Patuxent River and its tributaries. The meeting presentation and maps are available below:


March 2009 Presentation

Upper Little Patuxent Public Meeting #2 Presentation

(Note: If a potential project has a concept plan, you can view the concept plan by clicking on the site label on the Watershed Study Results Map.)

The final report and watershed results map for the Upper Little Patuxent Watershed Management Plan is available below:

Final Report

Watershed Study Results Map

For additional information, please contact Mark Richmond at 410-313-6413 or msrichmond@howardcountymd.gov.

Watershed Assessment Mapping

South Branch Patapsco River

Patapsco River Lower North Branch – Upstream

Patapsco River Lower North Branch – Midstream

Patapsco River Lower North Branch – Downstream

Brighton Dam/Triadelphia Reservoir

Rocky Gorge Reservoir

Patuxent River Upper

Watershed Surveys

What is a watershed survey?

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

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).


First Round

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

Middle Patuxent Watershed
Middle Patuxent Watershed

Rocky Gorge, Hammond Branch, and Dorsey Run Watersheds
Rocky Gorge, Hammond Branch, and Dorsey Run Watersheds

Patapsco Watersheds
Patapsco Watersheds and Appendices


Second Round

Cattail Creek and Brighton Dam
2005 Cattail Creek and Brighton Dam

Little Patuxent Watershed
2006 Little Patuxent Biomonitoring Survey

Middle Patuxent Watershed
2007 Middle Patuxent Biomonitoring Survey

Patapsco
2008 Patapsco Biomonitoring Survey

Rocky Gorge, Hammond Branch and Dorsey Run
2009 Rocky Gorge, Hammond Branch and Dorsey Run Biomonitoring Survey


Third Round

There were no Biomonitoring Surveys performed for 2010 and 2011.

Cattail Creek and Brighton Dam
Cattail Creek and Brighton Dam

Upper, Middle, Lower Little Patuxent
2013 Upper, Middle, Lower Little Patuxent Watershed

Upper, Middle, Middle Middle, and Lower Middle Patuxent
2014 Upper Middle, Middle Middle, and Lower Middle Patuxent Watershed

South Branch Patapsco, Patapsco River Lower Branch A and B
2015 South Branch Patapsco, Patapsco River Lower Branch A and B

Dorsey Run, Hammond Branch, and Rocky Gorge
2016 Dorsey Run. Hammond Branch, and Rocky Gorge Watersheds


Fourth Round

Cattail Creek and Brighton Dam
2017 Cattail Creek and Brighton Dam

 

For more information on the stream surveys conducted by the Stormwater Management Division, please call Max Anthony at 410-313-6432.

Watershed Implementation Plan

Watershed Implementation Plan

The WIP II has now been developed for Howard County and can be viewed by clicking on this link. Contact Mark Richmond at 410-313-6413 or msrichmond@howardcountymd.gov or 410-313-6444 for further questions about the WIP II plan.


Watershed Restoration Action Strategy (WRAS)

Little Patuxent WRAS

In 2001, The Stormwater Management Division was awarded a $45,000 grant by the Department of Natural Resources, to study and improve the water quality in the streams of Little Patuxent River Watershed. The purpose of the grant was to develop a Watershed Restoration Action Strategy (WRAS) that would restore and protect water quality and habitat, and answer the need for community environmental education. The scope of the work involved developing a watershed restoration plan that identified and prioritized actions and strategies. The results of the plan included:

    • collecting existing information on the watershed, from County and State sources;
    • adding research results from a planned bio-monitoring study in selected areas of the watershed to look closely at water quality indicators, including examination of stream creatures and their tolerance to pollution;
    • conducting a forest assessment that documented the location, acreage and condition of existing forest cover throughout the watershed. The assessment also indicated areas in need of riparian (along river or stream) buffers; and
    • implementing a public outreach and education campaign for community involvement, including residential, business, and farm interests.

    In 2002, Howard County received a $35,000 grant to implement the Little Patuxent Watershed Restoration Action Strategy. The grant's objective was to plant trees along stream edges in order to protect the stream. The trees were planted on County parkland in the Fall of 2002. The County is also working on a public outreach project to plant trees on private land within the Little Patuxent. Residents who live near a stream in the Little Patuxent may be eligible for free trees.

    Click on the link to read the Little Patuxent WRAS Report

Patapsco WRAS

In 2005, Howard County was awarded a $40,000 grant to conduct a WRAS in the Patapsco watershed. The first year of the WRAS involved analyzing data collected by the Department of Natural Resources and determining what restoration work will be done in the watershed. Click on the link to read the Lower Patapsco WRAS Final Report.