Final 1998 Report on Unified Watershed Assessment, Watershed Prioritization and Plans for Restoration Action Strategies


Parris N. Glendening

Kathleen K. Townsend
Lieutenant Governor


Produced by: Clean Water Action Plan Technical Workgroup

Under the Guidance of:
 * Maryland Bay Cabinet,

 * Maryland State Conservationist,
 * Representatives of Local Governments, and
 * Maryland's Tributary Teams

Final version: December 31, 1998

President Clinton's national Clean Water Initiative to restore and protect the streams, rivers, lakes, estuaries, and coastal bays of the United States is an effort we in Maryland wholly endorse and support as it is, in many ways, patterned after our own initiatives to preserve and protect our precious Chesapeake Bay. Therefore, we have been very pleased to note the progress we Marylanders have made to implement this strategy. We commend those who have already invested their time and energy into this initiative and we encourage those who's task it will be to implement this plan to keep in mind, that as President Clinton said that we must act now to provide "new protections to give all our children the gift of clean, safe water in the 21st century."

Parris N. Glendening         Kathleen K. Townsend
Governor                             Lieutenant Governor

For further information regarding this report, contact Dr. Paul Massicot at:
   1-877-620-8367, extension 8682 or via e-mail.
For additional information about the Maryland Clean Water Action Plan visit the State's Internet sites:

j This is an electronic hypertext report of the Maryland Department of Natural Resources.









Appendix I - Relationship between State watersheds and federal basins
Appendix II - List of contacts sent requests for supplemental data
Appendix III - Summary of indicators selected to identify Category 1 and 3 watersheds
Appendix IV - Example watershed profile
Appendix V - Public outreach meetings


 1. Benchmarks/thresholds for Category 1 (Restoration) watersheds
 2. Category 1 data by Maryland watershed

 3. Benchmarks/thresholds for Category 3 (Protection) watersheds
 4. Category 3 data by Maryland watershed  5. Category 1 (Restoration) watersheds
 6. Category 3 (Protection) watersheds
 7. Federal Category 1 (Restoration) basins
 8. Category 1 Priority (Restoration) watersheds
 9. Watersheds sharing Category 1 Priority and Selected Category 3 characteristics
10. Federal Category 1 Priority basins


1. Federal basins in Maryland
2. State watersheds
3. Category 1 (Restoration) watersheds
4. Category 3 (Protection) watersheds
5. Selected Category 3 (Protection) watersheds
6. Federal Category 1 (Restoration) basins
7. Category 1 Priority (Restoration) watersheds
8. Watersheds sharing Category 1 Priority and Selected Category 3 characteristics
9. Federal Category 1 Priority basins


The Clean Water Action Plan was unveiled by President Clinton in February 1998. This Plan proposes a new collaborative effort by state, federal, and local governments, the private sector and the public to restore those watersheds not meeting clean water and other natural resource goals and to sustain healthy conditions in watersheds that currently meet these goals. The Clean Water Action Plan addresses all aspects of watershed condition: water quality, including public health issues; aquatic living resources; physical habitat and the landscape. The key steps in this national effort are:

This report describes Maryland's Unified Watershed Assessment, Watershed Restoration Priorities and process under development to identify and implement Watershed Restoration Action Strategies. It was prepared by the Maryland Clean Water Action Plan Technical Workgroup and subject to policy review by a group including Maryland's Chesapeake Bay Cabinet Secretaries and the Maryland Natural Resource Conservation Service State Conservationist. Comments received from other local governments, State and federal agencies, interest groups and the public based on draft reports produced in August and October 1998 were considered in this revision of the report. Also, public comments received through mid-October and comments received during six regional workshops held in cooperation with the Tributary Strategies Teams in September 1998 were considered. The Technical Workgroup established a committee focused on drinking water sources to review the CWAP information in these watersheds in response to comments received about the poor weighting given to these watersheds given their import as a human health issue.
Final recommendations on the Technical Committee's Priority Restoration watersheds and Selected Protection watersheds were forwarded to the Clean Water Action Plan Steering Committee on December 21, 1998. This report includes those final recommendations.



The purpose of the Unified Watershed Assessment is to assess the condition of Maryland's watersheds and, based on watershed condition, classify the watersheds into the following categories:

The Unified Watershed Assessment (UWA) provides the foundation for setting watershed restoration, protection, and preservation priorities. Accordingly, the UWA needs to consider all components of the watershed related to aquatic systems including biological, physical, and chemical characteristics and related landscape factors.

Watershed Scale

States are able to make assessments for watersheds at multiple scales under the Clean Water Action Plan, but the hydrologic unit "basins" established by the U.S. Geological Survey are to serve as the common scale for unified watershed assessments at the national level. There are portions of 20 of these federal basins in Maryland (Figure 1), with an average area in Maryland of about 500 square miles (for comparison, the average area of a Maryland county is about 400 square miles). The condition of the Maryland portion of these federal basins can be determined either directly or as a result of aggregation of assessments of smaller watersheds. Maryland has chosen the latter approach because information at smaller watershed scales will be invaluable when Watershed Restoration Action Strategies are prepared.

Figure 1 
Maryland has identified smaller watersheds (Figure 2) at scales that, for the most part, fall inside or "nest" within the larger federal basins. For this report, the State's assessment is focused on smaller watersheds. There are 138 of these State-defined "8-digit" watersheds in Maryland, each with an average area of about 75 square miles. The relationships between the State's Tributary Strategy watersheds, the State's "8-digit" watersheds and the federal hydrologic units are shown in Appendix I.
Figure 2 
Local governments and other agency studies may identify even smaller watersheds that nest within this Statewide system. Identifying intensive monitoring and restoration activities by state and local governments or non-governmental organizations within these sub-watersheds may be desirable when reviewing watershed priorities or establishing watershed restoration action strategies.

Overall Goals

Two overarching goals were considered in the assessment of Maryland watersheds:

Clean Water Goals

To evaluate clean water goals, the assessment generally examined single factors that result in, or cause, a violation of the numeric/narrative water quality standards described in the Code of Maryland Regulations (§26.08.02). The State's biennial water quality report, required by Section 305(b) of the Federal Water Pollution Control Act Amendments, is a primary source of information about water quality impairments in the State. This report provides a summary of violations of State water quality standards as well as information about defined use impairments such as shellfish harvesting closures, swimming and water contact bans, fish consumption advisories. Much of the summary data about impaired waters and violations of State water quality standards in the 305(b) report are used to develop the list of impaired waters required under Section 303(d) of the Act. The final, EPA-approved listing of impaired waters on the State's 303(d) list through 1998 was incorporated in this Unified Watershed Assessment report.

Other Natural Resource Goals

To evaluate other natural resource goals, multiple and cumulative impacts that prevent watersheds from achieving healthy watershed conditions were assessed using selected natural resource indicators (listed below). These indicators relate to the condition of water chemistry, aquatic living resources, physical habitat and landscape.

Initial assessments used existing data from state monitoring and assessment programs. These constitute the core data for the Unified Watershed Assessment. In addition, supplemental information was solicited from several hundred individuals and organizations, such as local governments and community watershed associations, encouraging them to submit available water quality and aquatic resource information (Appendix II). Some supplemental data was received and results were evaluated and applied to assessment and prioritization activities.

Watershed Assessment Methods

In this section, the term "indicator" is widely used. Assessing the condition of the State's water quality and natural resources is a difficult undertaking. Not only are these natural conditions complex, but various human activities and impacts adds to the level of complexity.

One way to present the condition of our watersheds is to develop understandable measures or indicators that provide information about these resources. Scientists, managers and the public can use this information to determine the status of these resources, determine information about the pressures that degrade environmental quality, evaluate programs or changes in behavior designed to improve the environment. Over time, indicators help us measure our progress towards meeting our goals.

Category 1 (Restoration) Watersheds

Both the violation of water quality standards, as reflected by inclusion on the 303(d) List, as well as poor values for other natural resource indicators, are used as criteria for determining whether a watershed is classified as a Category 1 watershed "in need of restoration":

Many data sets that could be used as natural resource indicators were examined. A minimal number of indicators were selected that would provide the most accurate, non-duplicative, and comprehensive assessment of watershed condition. These indicators could be grouped into several major "clusters" that focused on the key areas of watershed condition:

Water Chemistry

Aquatic Living Resources Instream physical habitat


Data sources and methods of calculation for these indicators are briefly discussed in Appendix III. More information about these indicators are available as "metadata" on the State's Clean Water Action Plan Internet site ( A set of "watershed profiles" for each of the State watersheds that summarizes these indicators is available in a separate report (Maryland Watershed Profiles, MD Dept. Natural Resources, 1998); an example is shown in Appendix IV of this report. Each profile includes a detailed map of the watershed, including sub-watershed boundaries, and a summary listing of data for the watershed).

To determine if a watershed does not meet a Natural Resource Goal, one of two decision-making criteria is used:

As an example of the first case, a Non-tidal Fish Index of Biotic Integrity score less than 6.0 indicates that fish communities in the watershed's streams are in poor condition, so the basin fails to meet that Natural Resource Goal. As an example of the second case, a watershed where the impervious surface coverage indicator was among the highest (i.e. worst) 25 percent among the State's watersheds would identify that basin as failing to meet that Natural Resource Goal.

Application of these criteria is described in Appendix III. Benchmarks or thresholds for each indicator are listed in Table 1 and the resulting data for each watershed are listed in Table 2.
Table 1. Benchmarks/thresholds for Category 1 (Restoration) watersheds

Condition of...     Indicator                                       Benchmark            
Water quality   Monitored Nutrient Concentrations:eutrophication lowest 25%
                Monitored Nutrient Concentrations:habitat        lowest 25%
                Modeled Nitrogen and Phosphorus Loading Rate     highest 25%

Aquatic Living  SAV Abundance                                    score = 1
  Resources     SAV Habitat Index                                score < 7
                Tidal Benthic Index of Biotic Integrity          score < 6
                Tidal Fish Index of Biotic Integrity             lowest 25%
                Anadromous Fish Index                            lowest 25%
                Non-Tidal Benthic Index of Biotic Integrity      score < 6 (sample n>=4)
                Non-Tidal Fish Index of Biotic Integrity         score < 6 (sample n>=4)
                Non-Tidal Instream Habitat Index                 lowest 25%

Landscape       Parameters Percent Impervious Surface            highest 25%
                Population Density                               highest 25%
                Historic Wetland Loss Density                    highest 25%
                Percent Unbuffered Streams                       highest 25%
                Soil Erodibility score ³ 0.275

Clean Water     303d List                                        presence

Category 2 (Preventative Action) Watersheds

To identify watersheds needing preventative actions to sustain water quality and aquatic life, the application of Category 1 indicators was modified to identify these watersheds. As such, any watershed that is not on the 303(d) List and meets all or all but one of the available Category 1 benchmarks in Table 1 was placed in Category 2.

Category 3 (Protection) Watersheds

Indicators selected to identify watersheds needing restoration (Category 1) are not necessarily the same indicators that might be used to identify pristine or high quality (Category 3) watersheds that might need additional levels of protection.

Many data sets were examined that would provide an accurate, unique and comprehensive assessment of desired, high quality water quality, natural resource or landscape conditions. Some of the selected Category 3 living resources indicators for pristine watersheds are the same as Category 1 indicators for watersheds needing restoration while others are not. For example, there are no tidal watersheds considered to have pristine or sensitive benthic communities, so the Tidal Benthic IBI used for Category 1 watersheds is not used to help identify Category 3 watersheds.

Other indicators appear useful only in assessing Category 3 watersheds. For example, trout spawning areas are an indicator of relatively pristine natural conditions and is used as a Category 3 indicator. This indicator would not be useful for Category 1 watersheds as the absence of trout spawning areas does not necessarily imply that a stream is degraded - it may never have had the natural conditions that are prerequisite for trout spawning. These indicators can be clustered under key living resource and landscape issues and others address special water use needs (i.e., drinking water and fish hatchery water supply):

Application of these indicators is described in Appendix III and results were compared to Category 3 indicators benchmarks that are listed in Table 3. Any watershed with two or more indicators meeting these criteria was placed in Category 3. As with Category 1 indicators, the results of Category 3 indicators are provided in the available "watershed profiles" (Maryland Watershed Profiles, MD Dept. Natural Resources, 1998 (see example in Appendix IV).

Table 3. Benchmarks/thresholds for Category 3 (Protection) watersheds

Condition of...         Indicator                                Benchmark          
Aquatic Living Tidal Benthic Index of Biotic Integrity         highest 25%
  Resources    Non-Tidal Instream Habitat Index                highest 25%
               Non-Tidal Fish Index of Biotic Integrity        score > 8 (sample n>=4)
               Imperiled Aquatic Species Indicator             score > 0
               Migratory Fish Spawning Area                    score > 0
               Anadromous Fish Index                           highest 25%
               Wetland-Dependent Species                       highest 25%
               Trout Spawning Area                             score > 0

Landscape      %Headwater Streams in Interior Forest           highest 25%
  Parameters   %Watershed Forested                             highest 25%
               Wildland Acres                                  presence

Special Water  Fish Hatchery Water Supply                      presence
  Quality      Number of Drinking Water Intakes                presence
The resulting Category 1 indicator data for each watershed are listed in Table 4.

Category 4 Watersheds (Insufficient Data)

The federal Clean Water Action Plan created another classification for watershed that do not have enough data to classify the watershed into Categories 1, 2 or 3; these are Category 4 - Insufficient Data. Although the data available for different watersheds varies, the Workgroup determined that there was sufficient data to classify all State watersheds as Category 1, 2 or 3.

Results - State Watershed Level

The assessment results are summarized below. Category 1 (Restoration) watersheds are shown in Figure 3 and listed in Table 5. Watersheds with, at most, one indicator exceeding goals and not being identified on the State's 303(d) list, were identified as Category 2 (Preventative Action) watersheds (clear areas in Figure 3). Category 3 (Protection) watersheds are listed in Table 6 and shown in Figure 4. Watersheds with four or more indicators meeting Category 3 goals were listed as "Selected Category 3 Watersheds" (Table 6 and shown in Figure 5). All watersheds had sufficient data to allocate them to Category 1, 2 or 3 - thus, there are no Category 4 watersheds.

Because the selection criteria used for Category 1 (Restoration) and Category 3 (Preservation) watersheds are not the same and because land use and related factors may vary considerably within such a large watershed, many of the State's watersheds are identified as both Category 1 and 3 watersheds. These watersheds show signs of stress or degradation but still contain pristine or sensitive natural resources. For example, a watershed may have undisturbed headwaters but be significantly developed at its mouth. Unless watersheds are assessed at a scale where the land use is relatively homogeneous, Category 1 and Category 3 classifications are not mutually exclusive.

Figure 3 
Members of the Technical Workgroup and others observing the process suggested that some watersheds with special characteristics should be considered for listing as Protection watersheds in addition to those identified using the selected indicators. After publication of the August 1998 draft report, the following was added to the Category 3 watershed list:

Additional comments received in public hearings held around the State in September 1998 to discuss the Plan, and comments received in writing or at other public forums where the Clean Water Action Plan was discussed were considered by the Technical Workgroup. Several additional watersheds with special characteristics in need of protection were added to the Selected Category 3 list after the October 1, 1998 draft report was produced:  
Table 5. Category 1 (Restoration) watersheds (NOTE: segments are ordered by watershed code)
MD 8-digit Code Watershed Name MD 8-digit Code Watershed Name
02050301 Conewago Creek 02130807 Middle River - Browns Creek
02120201 Lower Susquehanna River 02130901 Back River
02120202 Deer Creek 02130902 Bodkin Creek
02120204 Conowingo Dam-Susq. Run 02130903 Baltimore Harbor
02120205 Broad Creek 02130904 Jones Falls
02130102 Assawoman Bay 02130905 Gwynns Falls
02130103 Isle of Wight Bay 02130906 Patapsco River
02130104 Sinepuxent Bay 02130907 Liberty Reservoir
02130105 Newport Bay 02131001 Magothy River
02130106 Chincoteague Bay 02131002 Severn River
02130201 Pocomoke Sound 02131003 South River
02130202 Lower Pocomoke River 02131004 West River
02130203 Upper Pocomoke River 02131005 West Chesapeake Bay
02130204 Dividing Creek 02131101 Lower Patuxent River - tidal
02130205 Nassawango Creek 02131102 Middle Patuxent River - tidal
02130206 Tangier Sound 02131103 Western Branch
02130207 Big Annemessex River 02131104 Patuxent River upper
02130208 Manokin River 02131105 Little Patuxent River
02130301 Lower Wicomico River 02131106 Middle Patuxent River
02130302 Monie Bay 02131107 Rocky Gorge Dam
02130303 Wicomico Creek 02131108 Brighton Dam
02130304 Wicomico River Headwaters 02140101 Lower Potomac River -tidal
02130305 Nanticoke River 02140102 Middle Potomac River - tidal
02130306 Marshyhope Creek 02140103 St. Mary's River
02130307 Fishing Bay 02140104 Breton Bay
02130308 Transquaking River 02140105 St. Clement Bay
02130401 Honga River 02140106 Wicomico River
02130402 Little Choptank 02140107 Gilbert Swamp
02130403 Lower Choptank 02140108 Zekiah Swamp
02130404 Upper Choptank 02140109 Port Tobacco River
02130405 Tuckahoe Creek 02140110 Nanjemoy Creek
02130501 Eastern Bay 02140111 Mattawoman Creek
02130502 Miles River 02140201 Upper Potomac River - tidal
02130503 Wye River 02140202 Potomac River MO County
02130504 Kent Narrows 02140203 Piscataway Creek
02130505 Lower Chester River 02140204 Oxon Creek
02130506 Langford Creek 02140205 Anacostia River
02130507 Corsica River 02140206 Rock Creek
02130508 Southeast Creek 02140207 Cabin John Creek
02130509 Middle Chester River 02140208 Seneca Creek
02130510 Upper Chester River 02140301 Potomac River FR County
02130511 Kent Island Bay 02140302 Lower Monocacy River
02130601 Lower Elk River 02140303 Upper Monocacy River
02130602 Bohemia River 02140304 Double Pipe Creek
02130603 Upper Elk River 02140305 Catoctin Creek
02130604 Back Creek 02140501 Potomac River WA County
02130605 Little Elk Creek 02140502 Antietam Creek
02130608 Northeast River 02140503 Marsh Run
02130609 Furnace Bay 02140504 Conococheague Creek
02130610 Sassafras River 02140505 Little Conococheague
02130611 Stillpond-Fairlee 02140507 Tonoloway Creek
02130701 Bush River 02140512 Town Creek
02130702 Lower Winters Run 02141001 Potomac River Lower N Branch
02130703 Atkisson Reservoir 02141002 Evitts Creek
02130704 Bynum Run 02141003 Wills Creek
02130705 Aberdeen Proving Ground 02141004 Georges Creek
02130706 Swan Creek 02141005 Potomac River U N Branch
02130801 Gunpowder River 02141006 Savage River
02130802 Lower Gunpowder Falls 05020201 Youghiogheny River
02130803 Bird River 05020202 Little Youghiogheny R
02130804 Little Gunpowder Falls 05020203 Deep Creek Lake
02130805 Loch Raven Reservoir 05020204 Casselman River
02130806 Prettyboy Reservoir -- --

Members of the Technical Workgroup and some public comments received on the draft report suggested that watersheds that serve as part of significant public drinking water supplies also should be considered for restoration and protection. A committee of selected representatives of State and local government agencies examined these issues and recommended to the Workgroup that several watersheds be added to the Category 1 and 3 lists. The Workgroup reviewed this list and added one watershed to the Category 1 (Restoration) list:

The Technical Workgroup also listed three other water supply watersheds as Selected Category 3 (Protection) watersheds:  
Figure 4 

Table 6. Category 3 (Protection) watersheds.
(NOTE: Highlighted watersheds are "Selected Category 3" watersheds. Segments are ordered by watershed code)
MD 8-Digit Code
Watershed Name
MD 8-Digit Code
Watershed Name
Lower Susquehanna River
South River
02120202 Deer Creek 02131004 West River
02120203 Octoraro Creek 02131005 West Chesapeake Bay
02120204 Conowingo Dam Susq Run 02131101 Patuxent River Lower tidal
02120205 Broad Creek 02131102 Patuxent River Middle tidal
02130105 Newport Bay 02131103 Western Branch
02130106 Chincoteague Bay 02131105 Little Patuxent River
02130201 Pocomoke Sound 02131107 Rocky Gorge Dam
02130202 Lower Pocomoke River 02131108 Brighton Dam
02130203 Upper Pocomoke River 02140101 Potomac River Lower tidal
02130204 Dividing Creek 02140102 Potomac River Middle tidal
02130205 Nassawango Creek 02140103 St. Mary's River
02130206 Tangier Sound 02140104 Breton Bay
02130207 Big Annemessex River 02140105 St. Clements Bay
02130208 Manokin River 02140106 Wicomico River
02130301 Lower Wicomico River 02140107 Gilbert Swamp
02130302 Monie Bay 02140108 Zekiah Swamp
02130303 Wicomico Creek 02140109 Port Tobacco River
02130305 Nanticoke River 02140110 Nanjemoy Creek
02130306 Marshyhope Creek 02140111 Mattawoman Creek
02130307 Fishing Bay 02140201 Potomac River Upper tidal
02130308 Transquaking River 02140202 Potomac River MO County
02130401 Honga River 02140203 Piscataway Creek
02130404 Upper Choptank 02140205 Anacostia River
02130405 Tuckahoe Creek 02140206 Rock Creek
02130503 Wye River 02140208 Seneca Creek
02130506 Langford Creek 02140302 Lower Monocacy River
02130508 Southeast Creek 02140303 Upper Monocacy River
02130509 Middle Chester River 02140304 Double Pipe Creek
02130510 Upper Chester River 02140305 Catoctin Creek
02130601 Lower Elk River 02140501 Potomac River WA County
02130602 Bohemia River 02140502 Antietam Creek
02130603 Upper Elk River 02140503 Marsh Run
02130604 Back Creek 02140504 Conococheague Creek
02130606 Big Elk Creek 02140505 Little Conococheague
02130608 Northeast River 02140506 Licking Creek
02130609 Furnace Bay 02140507 Tonoloway Creek
02130702 Lower Winters Run 02140508 Potomac River AL County
02130703 Atkisson Reservoir 02140509 Little Tonoloway Creek
02130801 Gunpowder River 02140510 Sideling Hill Creek
02130802 Lower Gunpowder Falls 02140511 Fifteen Mile Creek
02130804 Little Gunpowder Falls 02140512 Town Creek
02130805 Loch Raven Reservoir 02141001 Potomac River Lower N Br.
02130806 Prettyboy Reservoir 02141002 Evitts Creek
02130901 Back River 02141003 Wills Creek
02130903 Baltimore Harbor 02141004 Georges Creek
02130905 Gwynns Falls 02141005 Potomac River Upper N Br.
02130906 Patapsco River 02141006 Savage River
02130907 Liberty Reservoir 05020201 Youghiogheny River
02130908 S Branch Patapsco 05020202 Little Youghiogheny River
02131001 Magothy River 05020203 Deep Creek Lake watershed
02131002 Severn River 05020204 Casselman River

Figure 5 

Results - Federal Basin Level

In aggregating information from the smaller Maryland watersheds to the larger federal basins, the Clean Water Action Plan guidance was followed. Thus, federal Category 1 basins include those where the area of component Maryland Category 1 watersheds comprise at least 15 percent of the area of the federal basin (in Maryland). In following this guidance, all of the federal basins in Maryland with any significant size are identified as Category 1 watersheds.

The State's interpretation of the Unified Watershed Assessment guidelines is that a federal basin can be placed in only one of the four Categories. If a federal basin has characteristics of both Category 1 and Category 3, it will be listed as Category 1 in the federal compilation. This same decision rule is applied to Category 2 watersheds as well as Category 4 watersheds (of which there are none in Maryland). Therefore, for purposes of reporting results aggregated to the level of the federal basins, we place each federal basin only in one category, Category 1 (Table 7; Figure 6).

Table 7. Federal Category 1 (Restoration) basins (NOTE: segments are ordered by watershed code)
Federal HUC
Basin Name
Federal HUC
Basin Name
02050301 Lower Susquehanna 02060006 Patuxent
02060010 Chincoteague 02070011 Lower Potomac
02060009 Pocomoke 02070010 Middle Potomac-Anacostia-Occoquan
02060007 Blackwater-Wicomico 02070008 Middle Potomac-Catoctin
02060008 Nanticoke 02070009 Monocacy
02060005 Choptank 02070004 Conococheague-Opequon
02060002 Chester-Sassafras 02070003 Cacapon-Town
02060003 Gunpowder-Patapsco 02070002 North Branch Potomac
02060004 Severn 05020006 Youghiogheny

Figure 6 


After identifying all watersheds that do not meet clean water or other natural resource goals (Category 1 Watersheds), the Clean Water Action Plan calls for the selection of the set of these watersheds that are most in need of restoration during the next two years. These are defined as Category 1 Priority Watersheds. Furthermore, the schedule for these restoration and protection actions must be coordinated with the State's schedule to determine Total Maximum Daily Loads for pollutants from watersheds on the Section 303(d) of the Clean Water Act.

Results - State Watershed Level

The Clean Water Action Plan Technical Workgroup reviewed a number of methods for identifying Priority Watersheds. As results generated for each method was examined, it was determined that the different methods produced similar results when selecting priority watersheds. This produced confidence that the overall approach actually reflects the condition of the watersheds (and their need for restoration) and not just the particular method selected.

Category 1 Priority Watersheds were defined as watersheds that failed to meet at least half of their goals; i.e., at least half of the indicators had values failing to meet Category 1 benchmarks listed in Table 1. This method gives full consideration of all watersheds (since it does not "penalize" regions for which fewer statewide data are available, such as the Coastal Bays) and it is simple to calculate. The principal drawback is that this method equally weighs all 17 indicators. As a result, if there are more indicators that relate to a particular aspect of watershed health; e.g. biological integrity, these areas could carry more weight in the ranking process.

The Technical Workgroup recognized that other factors also should be examined to see if they warrant including additional watersheds in the Category 1 Priority list. These included severity of impact (e.g. Pfiesteria outbreaks) and evaluation of new data. For these reasons, three additional watersheds were included in the Category 1 Priority list in the August draft report:

Information received from the Bureau of Mines after the August 1998 draft report was produced was evaluated by the Technical Workgroup. These data showed that some streams in Western Maryland have biological communities in exceptionally poor condition; the Workgroup added the Upper North Branch Potomac River to the list of Category 1 Priority watersheds.

Comments received at public hearings held in the State in September and in writing were considered by the Technical Workgroup. The Department of Agriculture had identified the Upper Choptank River watershed as a priority watershed for potential nutrient loading to Chesapeake Bay. As other priority watersheds already were identified as Category 1 Priority watersheds, the Workgroup added this watershed after the October 1 draft report was produced.

Members of the Technical Workgroup and some public comments received on the draft report suggested that watersheds that serve as part of significant public drinking water supplies also should be considered for restoration and protection. A committee of selected representatives of State and local government agencies examined these issues and recommended to the Workgroup that several watersheds be added to the Category 1 and 3 lists. The Workgroup reviewed this list and added five water supply watersheds as Category 1 Priority watersheds:

These Category 1 Priority watersheds (Table 8, Figure 7) are recommended for restoration actions during the next two years. It is important to remember that many other Category 1 watersheds also warrant restoration actions. On-going and planned restoration activities in these watersheds will continue and that future efforts, funded by federal, State and local funds, will address these watersheds.

Table 8. Category 1 Priority (Restoration) watersheds (NOTE: segments are ordered by watershed code)
MD 8-digit Code Watershed Name MD 8-digit Code Watershed Name
02130102 Assawoman Bay 02130902 Bodkin Creek
02130103 Isle of Wight Bay 02130903 Baltimore Harbor
02130105 Newport Bay 02130904 Jones Falls
02130202 Lower Pocomoke River 02130905 Gwynns Falls
02130203 Upper Pocomoke River 02130907 Liberty Reservoir
02130208 Manokin River 02131002 Severn River
02130301 Lower Wicomico River 02131003 South River
02130304 Wicomico River Headwaters 02131102 Middle Patuxent River - tidal
02130308 Transquaking River 02131103 Western Branch
02130404 Upper Choptank 02131104 Patuxent River upper
02130405 Tuckahoe Creek 02131105 Little Patuxent River
02130503 Wye River 02131107 Rocky Gorge Dam
02130506 Langford Creek 02131108 Brighton Dam
02130507 Corsica River 02140104 Breton Bay
02130509 Middle Chester River 02140111 Mattawoman Creek
02130511 Kent Island Bay 02140203 Piscataway Creek
02130603 Upper Elk River 02140204 Oxon Creek
02130604 Back Creek 02140205 Anacostia River
02130610 Sassafras River 02140206 Rock Creek
02130611 Stillpond-Fairlee 02140207 Cabin John Creek
02130701 Bush River 02140208 Seneca Creek
02130704 Bynum Run 02140302 Lower Monocacy River
02130706 Swan Creek 02140303 Upper Monocacy River
02130802 Lower Gunpowder Falls 02140305 Catoctin Creek
02130803 Bird River 02140502 Antietam Creek
02130805 Loch Raven Reservoir 02140504 Conococheague Creek
02130806 Prettyboy Reservoir 02141004 Georges Creek
02130807 Middle River-Browns Ck 02141005 Potomac River U N Branch
02130901 Back River 05020203 Deep Creek Lake watershed

Figure 7 

As discussed in a previous section, because of different criteria, some State watersheds qualify as both Restoration and Protection watersheds. Fewer watersheds are identified both as Category 1 Priority watersheds and Selected Category 3 watersheds (Table 9; Figure 8). The State considers that these watersheds deserve special attention in order to address degradation that already is experienced in some areas before the pristine resources in the watershed are lost.

Table 9. Watersheds sharing Category 1 Priority and Selected Category 3 characteristics
(NOTE: segments are ordered by watershed code)

MD 8-digit Code Watershed Name MD 8-digit Code Watershed Name
02130202 Lower Pocomoke River 02140111 Mattawoman Creek
02130503 Wye River 02140208 Seneca Creek
02130603 Upper Elk River 02140302 Lower Monocacy River
02130805 Loch Raven Reservoir 02140303 Upper Monocacy River
02130806 Prettyboy Reservoir 02140502 Antietam Creek
02130905 Gwynns Falls 02141004 Georges Creek
02130907 Liberty Reservoir 02141005 Upper N Branch Potomac River
02131107 Rocky Gorge Dam 05020203 Deep Creek Lake watershed
02131108 Brighton Dam

The committee reviewing proposals for Federal FY1999 and FY2000 Clean Water Action Plan funds will consider projects located in watersheds sharing both Category 1 Priority and Selected Category 3 listings identified in this report as a high priority. Projects located in a Category 1 Priority watersheds will be considered as a second priority for funding. There are other criteria that will be used to review projects for funding including: maximizing water quality, habitat protection/restoration and other natural resource goals; addressing locally defined geographic priorities at scales smaller than the 138 watersheds evaluated in the Unified Watershed Assessment; using Section 6217 (Coastal Zone Management) measures that are a required part of the coastal nonpoint source pollution program; addressing issues of statewide concern (e.g., nutrient management, habitat goals for wetlands, siting/operation of septic systems, acid mine drainage, growth management); help achieve water quality standards in areas listed on Maryland's 303(d) list; partnering (support/endorsement) with Tributary Teams; implement recommendations contained in an existing watershed restoration strategy; and located within or supporting an EQUIP priority area.

Figure 8 

Results - Federal Basin Level

In terms of identifying federal Category 1 Priority basins, the same procedure used to identify federal Category 1 basins was used to aggregate information from the smaller Maryland watersheds to the larger federal basins. In following the federal Clean Water Action Plan guidance federal Category 1 Priority basins include those where the area of the State's Category 1 Priority watersheds comprise at least 15 percent of the area of the federal basin (within Maryland). In following this guidance, nearly all of the federal basins in Maryland with any significant size are identified as Category 1 Priority basins (Table 10; Figure 9).

Table 10. Federal Category 1 Priority basins (NOTE: Segments are ordered by watershed code)

Federal HUC Watershed Name Federal HUC Watershed Name
02060010 Chincoteague 02060006 Patuxent
02060009 Pocomoke 02070010 Middle Potomac-Anacostia-Occoquan
02060007 Blackwater-Wicomico 02070008 Middle Potomac-Catoctin
02060005 Choptank 02070009 Monocacy
02060002 Chester-Sassafras 02070004 Conococheague-Opequon
02060003 Gunpowder-Patapsco 02070002 North Branch Potomac
02060004 Severn 02050006 Youghiogheny

Figure 9 
Results - Interstate Comparison

A review of draft Clean Water Action Plan assessment reports from most every adjoining State (Delaware, Pennsylvania and West Virginia) and the District of Columbia, showed that, in spite of differing assessment methods, many of the federal watersheds that Maryland shares with these States are consistently identified as Category 1 (Restoration) watersheds. Assessment information from Virginia's draft report, which would address nearly half of the seventeen interstate federal watersheds, was not provided for analysis. Differences between State interpretation of watershed assessment categories were principally related to the amount of assessment information available.

Identifying Category 1 Priority watersheds in these draft reports showed considerably more variability between States as a result of regional water quality issues, local priorities and different approaches to prioritization. Pennsylvania had not completed their prioritization process. Delaware's prioritization process is governed by a formal consent decree with the US Environmental Protection Agency rather than water quality and other natural resource goals. It is expected that the federal Clean Water Action Plan report to Congress will address interstate variability in the assessment.

An example of a potential impact of different assessments of interstate watersheds was demonstrated in comments received from the Susquehanna River Basin Commission on the Maryland's draft Unified Watershed Assessment report. The letter noted that Pennsylvania might identify the Lower Susquehanna River basin as a Category 1 Priority watershed while Maryland identified its portion of the watershed as a Category 1 (Protection) watershed but not as a Category 1 Priority watershed.

This difference is mainly due to watershed scale and differences in land use with Maryland's portion of the Lower Susquehanna River basin being one of the smallest in the State. Maryland does recognize the importance of upstream activities to Susquehanna River water quality conditions that affect Chesapeake Bay and would support designation of the Lower Susquehanna River basin as a federal Category 1 Priority basin if funding opportunities for activities and discharges in the larger upstream portion of the watershed in Pennsylvania and New York would be affected by this designation. The State would consider similar support for other interstate basins where State assessment categories differ.


A Steering Committee has been formed to guide the Clean Water Action Plan process in Maryland. The Committee - made up of representatives from the USDA Natural Resources Conservation Service, the Department of Natural Resources, the Department of Environment, the Department of Agriculture, the Office of Planning, river commissions, Tributary Teams and local governments - outlined the principles that are guiding the State's development of Watershed Restoration Action Strategies.

In addition, a Technical Workgroup was formed to review existing information on watershed conditions and draft the Unified Watershed Assessment. The workgroup included a diverse group of interests: State agencies, local governments, Tributary Teams, environmental and watershed organizations, the Farm Bureau and others.

Outreach included six regional public meetings (Appendix V), hosted by Maryland's Tributary Teams, held around the State that reached over 300 people, including representatives of local governments, soil conservation districts, watershed organizations, educators, and citizens. Press releases were sent out to local newspapers, and meeting notices were sent to every county library in the State. Briefings have also been provided to the Tributary Teams, the Chesapeake Bay Program, watershed organizations, and other groups upon request.

In addition, the executive summary of the report was sent out to approximately 500 people. The executive summary and the report, background material, summary of comments and links to other Clean Water Action Plan sites are available to the public on the Department of Natural Resources web site: A mirror site also will be available on the Department of the Environment's Internet site.

Public comments received to date have touched on a range of issues. Common concerns have included:
the future impacts of growth on watersheds;

Many of these comments relate to implementation, rather than assessment issues, and will be considered in the implementation phase. Public comments on this report were accepted through October 15, and were considered in final revisions to this report.


The State's long term objective is to have Watershed Restoration Action Strategies (WRAS) that are comprehensive, and address all aspects of watershed condition and water quality, including public health; aquatic living resources; physical habitat and the landscape.

A WRAS will provide information and guidance that will help the public, watershed organizations, and federal, state and local agencies focus their staff and monies in areas and on issues important to the public and that will result in measurable environmental improvement.

The strategies may be drawn from existing assessment and targeting efforts such as a county's comprehensive plan, stormwater and sewer plans, capital budgets, greenways and open space plans, watershed stewardship programs, site design standards/BMPs, erosion and sediment control plans, soil conservation district watershed work plans and other efforts.

A comprehensive strategy includes the following:

WRAS need to be developed for watersheds in need of protection and restoration. The State has a number of "strategies" at the state and local level that include recommendations for water quality and natural resource restoration or protection. These existing strategies can form the foundation for strengthened, more comprehensive strategies that will maximize benefits for water quality and natural resource goals in a more holistic, coordinated manner.

Many strategies contain recommended "on the ground" implementation efforts to improve water quality and meet other natural resource goals such as aquatic health and habitat. Strategy actions will be supported through new funds authorized by the Clean Water Action Plan and channeled through existing programs such as §319, as well as through other State and local programs.

Watershed restoration strategies will be encouraged to:

Over the longer term, the Steering Committee will also address such outstanding issues as the potential for targeting additional funds to the Priority watersheds, future revisions to the Priority watershed list and the need to further coordinate the State's watershed restoration and protection efforts.

Pilot Lower Eastern Shore Conservation and Action Strategy

The Lower Eastern Shore has been selected as a pilot area for the development of the State's first Clean Water Action Plan Strategy. The purpose of this strategy is to coordinate and help to focus both ongoing restoration and conservation activities and potential new restoration funding available under the federal program. The Lower Eastern Shore Action Strategy is being coordinated through the Lower Eastern Shore Tributary Team with the assistance of State agencies. Local governments, the Tributary Team, Delaware state agencies, and other interested citizens and organizations will also be involved in strategy development and implementation.

The initial phase the action strategy will take the analysis in the Unified Watershed Assessment to a more detailed scale, comparing watersheds within the region to identify those most in need of restoration action, those with the greatest conservation values, and opportunities for restoration and protection. Such opportunities might include economic development interests, tourism and recreation initiatives, or the presence of a watershed association already involved in related activities. Since specific local water quality problems require specific solutions, the second phase of strategy development will be to match appropriate tools and new federal funding to particular projects in the impacted watersheds.


The federal Clean Water Action Plan has stimulated a comprehensive statewide assessment of Maryland's watersheds including a diverse set of factors addressing all aspects of watershed condition. This assessment has involved a broad spectrum of participants from local, state and federal agencies and representatives of many private organizations.

Much additional work to refine our assessment procedures remains to be done, since the time provided to accomplish this initial assessment has been very brief, given the magnitude of the undertaking. As mentioned above, review and evaluation of the available data, some of which is preliminary, will continue. In addition, these data will be supplemented by comments and suggestions from the public workshops, additional local and regional watershed data, and data obtained through mutual exchange with surrounding jurisdictions for interstate watersheds. As a result, the findings and conclusions contained in this report, including watershed restoration priorities, can be expected to undergo modification in the future.

The potential benefits of this approach for Maryland's watersheds are significant. The results of this process will ultimately provide a comprehensive framework which other programs can utilize to conduct coordinated activities on individual watershed issues. These benefits will only increase with the further evolution of the Clean Water Action Plan's Watershed Approach.

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