VACO/VML Meeting

Center for Watershed Protection

VACO/VML Meeting

June 2, 2010

David J. HirschmanProgram Director



• Non-profit 501(c)3, non-advocacy organization founded in 1992• Work with watershed groups, local, state and federal

governments• Provide tools to communities to protect lakes, rivers, streams,

and estuaries• 20 staff in Ellicott City, MD; Field Offices in Charlottesville, VA &

Ithaca, NY

www.cwp.org



$20K per acre



Stormwater Program Trade-Offs

Lots of Land Covered

Low Cost Uncertain Outcomes

Moderate Land Covered

Moderate Cost

Fairly Certain Outcomes

Small Areas Covered

High Cost Excellent Outcomes


Menu of Practices

• Green Roof*• Impervious

Disconnection*• Raintanks &

Cisterns*• Permeable

Pavement*• Grass Channels• Bioretention• Water Quality Swale

• Infiltration• Extended Detention

Pond• Soil Amendments*• Filtering Devices• Stormwater

Wetland• Wet Pond• Sheet Flow/Open

Space*


Hirschman’s Heroes

1. Watershed Forestry2. Rainwater Harvesting3. Bioretention4. Turf/Nutrient Management5. Nutrient Trading


1. Watershed Forestry


save energy improve air quality provide habitat better quality of life neighborhood stability aesthetic values increase property

value reduce noise good for business

Trees are the original “multi-taskers”


American Forests’ Urban Ecosystem Analysis

• The Washington, DC metropolitan area has 187,767 acres of tree canopy

• Stormwater retention capacity of the urban forest is 949 million cubic feet in avoided storage of water

• This storage capacity is valued at $4.7 billion (based on cost of $5/cubic foot to build equivalent retention facilities)

Source: American Forests (2002)


Influence of Forests and Impervious Cover on the Health of Streams

• Impervious cover

• Watershed tree cover

• Riparian buffer tree cover

Excellent good fair poorExcellent good fair poor

80-80-

70-70-

60-60-

50-50-

40-40-

30-30-

20-20-

10-10-

00

Stream health rating

perc

en

t

(Goetz, et.al, 2003)

For 245 watershedsFor 245 watersheds

Recommendations:Recommendations:

No more than 6% ICNo more than 6% ICAt least 65% riparian At least 65% riparian forest cover for Excellent forest cover for Excellent scorescore

No more than 10% ICNo more than 10% ICAt least 60% riparian At least 60% riparian forest over for Good score forest over for Good score


Identify forest conservation and reforestation priorities


Promote conservation of existing forests

Photo courtesy of Harford County DPW

Photo courtesy of Randall Arendt


Preserve/Restore aquatic buffers


Protect trees during construction


Require trees along new streets

More shade means more time between repaving. 20% shade on a street improves pavement condition by 11%, which is a 60% savings for

resurfacing over 30 years.


Plant trees in stormwater practices


Frederick County, MD SchoolsFrederick County, MD Schools

Since 2005, more than 4,500 trees have been planted.

By spring 2010, we will have planted more than 15 acres of new trees.

Slide Credit: Frederick Co, MD


2. Rainwater Harvesting


Source: Sanitation District No. 1 of Northern

Kentucky


3. Bioretention


Year 1

Year 3

Year 10

Improve with Age


4. Turf/Nutrient Management


5. Nutrient Trading – Watershed Based Program


Stormwater Accounting

•Real World

•Model World


The thatched roof for this building dripped rainwater into the stone carved channel in the foreground

Source: Wright Paleohydrological Institute


During medieval times, vegetated roofs were used in Scandinavia to improve insulationSource: http://www.roofgreening.ca/section/view?fnode=30


Hotel Atlantic View was established in 1928 as Hatteras Island's first hotel. It was built to provide accommodations for wealthy businessmen and industrialists of the era who traveled to the island for its renowned game hunting and sport fishing. Notice the cistern to the right of the building with the downspouts feeding it rain water from the roof.

Source: Hatteras Village – Then and Now (http://www.hatteras.biz)

Cistern


Conclusions

• Consider practices with multiple/local benefits

• Participate in process to advocate for preferred practices

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