Calvert County, MD

1. Subwatershed Planning
in Calvert County Maryland
Prepared for the
1st Annual Choose Clean Water –
Chesapeake Bay Restoration
Conference

2. A Clean‐up for the Bay – What to
Expect from the Bay TMDLs at the local level
• TMDL effect on the planning process
• TMDL integration with WRE of Comp
Plans
• Engaging stakeholders
• Eventual implementation of pollution
reduction measures

3. HB 1141: Water Resources
Water Resource Element
A. Analyze long‐term water needs
and supplies
B. Analyze the impact of sewer
treatment plants 15, 2008
September
C. Analyze the impact of stormwater
(diffuse sources)
3

4. But first of all,
where are we?

5. Calvert CountyWatersheds

6. Entire Watershed –Selected Data
Land Use Zoning 6

7. Patuxent Tributary
Goals
7
Maryland Tributary Strategy Patuxent River Basin, Summary Report for 1985-2005 Data, August 2007

8. HB 1141: Water Resources
Water Quality:
Patuxent River Basin
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9. 9
Maryland Tributary Strategy Patuxent River Basin, Summary Report for 1985-2005 Data, August 2007

10. 10
Maryland Tributary Strategy Patuxent River Basin, Summary Report for 1985-2005 Data, August 2007

11. 11
Maryland Tributary Strategy Patuxent River Basin, Summary Report for 1985-2005 Data, August 2007

12. HB 1141: Water Resources
Water Quality: Fresh
Water Stream Survey
12

13. Maryland Biological Stream Survey 2000-2004 County Results
Riparian Buffers
13

14. Maryland Biological Stream Survey 2000-2004 County Results
Physical Habitat
Index
14

15. Maryland Biological Stream Survey 2000-2004 County Results
Nitrate-Nitrogen
15

16. Maryland Biological Stream Survey 2000-2004 County Results
Total
Phosphorus
16

17. HB 1141: Water Resources
Water Quality: Based on
Land Use and Pollutant
Loads
17

19. Impervious
Surfaces
Most of our
subwatersheds have
less than 5%
impervious surfaces.
Two subwatersheds
would be considered
‘urban’ (more than
10% impervious
surfaces.)
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20. Forest canopy is
56-58%.
60% is
considered good.
20

21. HB 1141: Water Resources
So what can we conclude
from the data?
• Our nutrient loads are higher than we want.
• Erosion has caused significant stream damage
in places.
• There are opportunities for good water quality
• Impervious surfaces are still low and forest
cover is still high in most watersheds.
21

22. Smart Growth
• Priority
Preservation Areas
• Priority Funding
Areas
• Transition areas

23. HB 1141: Water Resources
Best Management Practices (BMPs)
and Projected Growth -Nitrogen
Total Nitrogen Load
1,200,000
1,000,000
800,000
Lbs/Yr
Total Septic Load
600,000
Total Terrestrial Load
400,000
200,000
0
2007 LU, 2007 LU, Scenario Scenario
2002 Trib Strat 1 Trib 2 Trib
BMPs BMPs Strat Strat
BMPs BMPs 23

24. HB 1141: Water Resources
Best Management Practices (BMPs)
and Projected Growth -Phosphorus
Total Phosphorus Load
70,000
60,000
50,000
Lbs/Yr
40,000
Total Phosphorus Load
30,000
20,000
10,000
0
2007 LU, 2007 LU, Scenario Scenario
2002 Trib Strat 1 Trib 2 Trib
BMPs BMPs Strat Strat
BMPs BMPs 24

25. Best Management Practices
include: Cover Crops . . . .

27. Non-structural
stormwater
management

28. Non-structural
stormwater
management

29. HB 1141: Water Resources
Best Management Practices BMPs and
Projected Growth –Impervious Cover
Total Impervious Cover
12,000
10,000
8,000
Acres
6,000 Total Impervious Cover
4,000
2,000
0
2007 LU, 2007 LU, Scenario Scenario
2002 Trib Strat 1 Trib 2 Trib
BMPs BMPs Strat Strat
BMPs BMPs 29

30. HB 1141: Water Resources
Best Management Practices BMPs and
Projected Growth –Forest and Agriculture
Forest and Agriculture
90,000
80,000
70,000
60,000
Acres
50,000 Forest
40,000 Agriculture
30,000
20,000
10,000
0
2007 LU, 2007 LU, Scenario 1 Scenario 2
2002 BMPs Trib Strat Trib Strat Trib Strat
BMPs BMPs BMPs 30

31. HB 1141: Water Resources
Proposed Stormwater
Actions
(diffuse sources)
31

32. HB 1141: Water Resources
Include the following:
•Set water quality goals.
•Prepare subwatershed plans.
•Continue to monitor water quality.
•Include tree ordinances, with tree canopy
goals, in all town center ordinances.
•Update the stormwater management
ordinance.
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33. By what standards should we
measure water quality?
Draft goals for fresh water:
• <0.71 milligrams of nitrogen per liter
• <0.031 milligrams of phosphorus per liter
• <10 TNUs of turbidity
Draft goals for tidal water:
• Chlorophyll <10 micrograms per liter of water
• Secchi Depth measurements > 1 meter
•Oxygen levels: 4 mg/l for deep waters and 6 mg/l
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for surface waters.

35. Draft goals for urban
subwatersheds > 10% impervious:
•Maintain swimmable/ fishable
water quality;
•Improve water clarity by reducing
sedimentation;
•Restore aquatic diversity in
freshwater streams;
•Increase groundwater recharge;
•Enhance waterfront access.
35

36. Draft goals for rural subwatersheds
< 10% impervious:
Achieve the goals of the urban
subwatersheds, plus the following:
•Maintain or restore anadromous (fish
spawning) streams
•Develop and maintain shellfish beds,
both sanctuary and open to
harvesting.
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37. Subwatershed Master Plans
• Build Partnerships
• Characterize Subwatershed
• Finalize Goals and Identify
Solutions
• Design Implementation
Program
• Implement Watershed Plans
• Measure Progress and make
adjustments.

38. Mill Creek:
One of two urban
subwatersheds in
Calvert County

39. Town Centers:
Stormwater from
two town centers
flow toward Mill
Creek

40. Zoning
-Town Center
-Residential
-Employment Center

41. Land Use
-Commercial
-Residential
-Public
-Undeveloped

42. Contour Map
The upper reaches
of the subwatershed
contain steep slopes

43. Tree Coverage
Approximately
40% of the
subwatershed has
tree coverage

44. Sewer vs. Septic
-Served by
Solomons Sewer
System
-Served by
traditional septic
systems
-Served by nitrogen-
removing system

45. Test sites
Annual harbor
study and the
Lower Restoration
Action Strategy

46. First Five
Subwatershed
Plans
• Hall Creek
• Fishing Creek
• Parker’s Creek
• Gray’s Creek
• Mill Creek

47. Building connections with
citizens
We have been:
• Collecting email addresses at public
presentations
• Collecting email addresses at community
meetings
• Notifying citizens of meetings via email
• Posting PowerPoints and videos on the web.

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49. Challenges
• Creating walkable communities while protecting
water quality.
• Developing mitigation strategies.
• Paying for infrastructure needed for smart growth.
• Determining the most cost effective tools to achieve
nutrient reduction.
• What to do first?