A.Strobridge-

Ashley Anne Strobridge GGS 307 – Sustainable Development Prof. Allison Richards Research Paper 5/11/2014

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The Impacts of Traditional Stormwater Management vs. Green

Infrastructure on the Chesapeake Bay Watershed; Especially

Concerning the Upper Potomac River Watershed and the Accotink

Creek Watershed

By: Ashley Anne Strobridge

Abstract:

Significant knowledge gaps exist on the variations in data between the impacts of

traditional stormwater management, vs. the impacts of green infrastructure on the

health of waterways. For the purpose of providing knowledge to fill in these gaps, this

research paper will explore articles containing data on water quality, land use, and

approaches to stormwater management in the Chesapeake Bay Watershed, as well as

flora and fauna species and economic factors affected by these variables, comparing the

results from the two above mentioned stormwater management techniques. Particular

attention will be paid to the water quality in Gunston Cove vs the water quality in the

upper Potomac River, both tributaries into the Chesapeake Bay , but with different

individual watersheds in Fairfax County and Montgomery County, respectively . Those

respective watersheds handle their stormwater in opposing ways, with Fairfax Co. using

a green infrastructure approach, and Montgomery Co. preferring a more traditional

method; this paper will look at the results of those approaches through studying water

quality assessments, land use maps, and stormwater management approaches of each of

these regions to assess which is most effective practice to preserve wildlife and the

ecosystem in an aquatic system: traditional stormwater management, or the installation

of green infrastructure.

Ashley Anne Strobridge

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Background:

The Chesapeake Bay Watershed extends across six U.S. states and the District of

Columbia. These states include New York, Pennsylvania, Delaware, West Virginia,

Maryland, and Virginia. According to the Chesapeake Bay Foundation (CBF), the

Chesapeake Bay is the largest coastal estuary in the world holding 18 trillion gallons of

water (CBF); this means that it is incredibly important to maintain its environmental

balance, as the National Wildlife Federation (NWF) states that it also supports over

3,600 individual species of flora and fauna (NWF), and many of these species are on the

threatened or endangered species list. According to the Federal Fish and Wildlife

Service’s Chesapeake Bay Field Office, in Maryland alone there are nine threatened

species, including the piping plover, and sixteen endangered species, including the

leatherback turtle and six mammals, four of which are whales (FWS), and this is only in

one state of the six states covered by the Chesapeake Bay Watershed.

Contributing to the problem of endangered and threatened species is the fact that

according to the Chesapeake Bay Foundation, Chesapeake Bay and its tidal rivers are on

the Clean Water Act's list of impaired waters. The impact of this listing is compounded

when one takes into account that the Chesapeake Bay produces over 500 million pounds

of seafood per year, adding not only to the amount of over-fished populations (the

Menhaden keystone species in particular), but to the health problems of the residents

who eat this seafood coming out of the impaired Chesapeake. For example, according to

the Virginia Dept. of Health, for fish caught in the entire Chesapeake Bay, there is

currently a PCB Fish Consumption Advisory (VDH). The health effects from PCBs are

nothing to dismiss easily, as a 1999 article by A. Brouwer states that the health effects


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from PCBs include endocrine disruption, and neurodevelopmental and reproductive

effects (Brouwer). Also, according to the Chesapeake Bay Foundation, “in the

Chesapeake region, governments have issued statewide fish-consumption advisories for

mercury for all lakes and rivers in Pennsylvania and Maryland, and for many rivers in

Virginia” (CBF). Yet people continue to fish from the Chesapeake and its tributaries

every year, in fact, fishing is one of Virginia and Maryland’s biggest tourist attractions.

However, if this industry is threatened much more from over-fishing and pollution, it

will impact the two states’ economies drastically, so there is definitely an incentive to

keep the Bay clean and the Bay’s fish populations healthy. So how can this be achieved?

Well partly, through proper storm-water management.

Earlier it was mentioned that the Bay holds 18 trillion gallons of water, and it

seems only natural to assume that much of the water comes from the Atlantic Ocean,

but as it turns out, only half of the water in the Bay comes from the ocean, the rest

comes from the 64,000 square mile, six-state watershed. That means that keeping the

watershed healthy is of utmost importance to the health of the Bay, and the one good

way to do that is to maintain healthy stormwater management techniques. But there are

many techniques utilized by the various regions throughout the Chesapeake Bay

Watershed; which ways are best? Well this paper will decipher the answer to that

question by surveying the different techniques, and the ecological impacts from each

region using the different approaches.

Every four years in the Chesapeake Bay Watershed, an area of land the size of

Washington, D.C. is converted from green filter to grey funnel. The landscape can be a

green filter, or a grey funnel. With a green filter, water that falls during rain-showers or


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storms is filtered naturally through the ground, through tree roots, dirt, other plant

roots, rocks, and pumice, which all filter out impurities from pollution. A green filter

would mean having natural plant life and non-paved ground available to water

filtration, and this is one of the things that green infrastructure provides. With a grey

funnel, however, the land is paved over, providing no way for toxins and pollution to be

naturally filtered through the ground. This paved-over land area feeds into the sewer

system, which frequently runs directly into waterways, which washes that pollution,

including trash and debris, into places like the Chesapeake Bay, furthering the pollution

issue, and making the Bay even more of an impaired waterway.

According to saveitlancaster.org and their Lancaster Green Infrastructure Plan

video posted to Youtube in 2012, Lancaster Pennsylvania, and many other cities in the

Chesapeake Bay Watershed, including Richmond, have a stormwater management

system that is very outdated. Currently, in these cities, there is a partially combined

sewer system, where most of the time, waste water from toilets is diverted to water

treatment plants, and grey water is sent directly into rivers and streams, using the grey

funnel system. This may seem alright, but as mentioned previously, when you have

water running directly into the waterways off of pavement, there is a lot of pollution that

doesn’t get filtered, and ends up in the waterways, which will be explored further in the

next paragraph. Also, with a partially combined sewer system, when there is a massive

storm and influx of rainwater into that system, it also washes untreated sewer waste into

the rivers, because the sewer system just can’t handle all that water at one time.

There are many negative effects from having a grey funnel system for storm water

management, and one of these is dead zones from the polluted stormwater run-off.


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Dead zones occur when excesses of nitrogen and phosphorous pollution from human

activities such as farming, lawns, and pest control end up in the water ways and cause

massive fish kills. According the Chesapeake Bay Foundation, “Both nitrogen and

phosphorus feed algal blooms that block sunlight to underwater grasses and suck up life

supporting oxygen when they die and decompose” (CBF). The implications of this are

that the water is then oxygen deprived, meaning that fish and other sea creatures can’ t

survive in the water. Also because the sunlight is blocked from the grasses, the grasses

die off too, further depleting the water of oxygen due to the lack of photosynthesis

occurring, and removing habitat for spawning fish, crabs, and other sea-life. Sediment

deposits also kill off grasses, and this is caused by lack of natural buffers like trees and

plant life along riparian zones. This also means that when stormwater run-off from the

grey funnels of cities is rushed at break-neck speed by paved tributaries into the more

natural areas, and there is massive erosion of the stream and river banks, causing

sediment to be rushed into the Bay.

These issues currently facing the Bay are caused by over-development of the land,

and lack of proper stormwater management. According to the Chesapeake Bay

Foundation, over the past 15 to 20 years, development has been the largest cause of

forestland loss in the Bay Watershed. Between 1982 and 1997, 750,00 acres of

forestland were developed – a rate of about 100 acres per day. This loss leads to the loss

of air and water filters, wildlife habitat, and other significant functions that forests

provide. Development also causes more sediment pollution to run into and muddy our

waters and the Bay throughout the initial construction phase, the same sediment that


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kills off grasses in the Bay, creating fish kills, and disrupting the food web for birds that

eat the young fish that would have spawned in those grasses.

But it is not just the initial construction phase that causes this disruption. For the

last few decades, construction has mainly meant creating more impermeable surfaces,

or pavement and grey funnels, which means not just more sediment in the water, but

pollution as well. As was discussed earlier, nitrogen and phosphorous ends up in the

waterways through run-off from lawns and farms, but other things also end up in the

Bay from run-off that doesn’t get filtered through green funnels. Many of these come

from non-point sources such as E. coli from pet waste, and toxins and oil leaked from

cars onto the pavement, which then washes in to the rivers, and ends up in the Bay.

According to the phillywatersheds.org video, Green City, Clean Waters, just one inch of

rain falling on one acre of paved surface equals 27,000 gallons of polluted runoff.

According to the Environmental Protection Agency, urban and suburban

stormwater is the source of about 15 percent of the total nitrogen entering the Bay, and

is the only source that is still increasing (EPA). This means that polluted urban and

suburban run-off is still a growing problem. According to the Chesapeake Bay Program,

in 2011, 40 million lbs. of polluted runoff from urban and suburban sources ended up in

the Bay. But there is hope to reduce that number by 2025 by implementing green

infrastructure in the Chesapeake Bay Watershed region.

As was mentioned earlier in this paper, green infrastructure includes planting

trees in riparian zones, and having unpaved surfaces where water can filter naturally

through the ground to cleanse it of pollutants. But there are many ways to create green

infrastructure. These include paving sidewalks, roads, parking lots, and basketball


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courts with permeable pavement to filter water through a series of layers of stone and

pumice before the water is returned to the streams, or installing rain-barrels to catch

water coming off of roofs in order to hold it to water lawns or gardens. Another way to

deal with water on one’s roof through green infrastructure is to install green roofs, or

rooftop gardens, which will use water falling on the roof to feed the plants that grow

there in a thin layer of soil; this technique also helps to insulate the building, which can

be a money saver. According to the Chesapeake Bay Foundation, things that individual

citizens can do more easily are to create pervious walkways and driveways of crushed

stone, mulch, or other materials that return rainwater to the ground. Citizens can also

reconfigure yard space to create rain gardens in low-lying areas, and replace grass turf

with native plants (CBF), which don’t need the fertilizer or pesticide, avoiding nutrient

problems for the Bay.

Some may ask, what is the financial cost of installing all this green infrastructure,

and is it worth it? Well this paper also explores the financial benefit of having a clean

Bay, and the costs of not having a healthy Chesapeake Bay. According to the Chesapeake

Bay Foundation’s study “What is the Value of the Chesapeake Bay and Virginia’s

Waterways?”, a 2006 study compared the 1996 water quality of the Bay with what it

would have been without the Clean Water Act, and with the Act there were benefits of

$357.9 million to $1.8 billion in recreation and tourist income to just Virginia due to

cleaner water to recreate in. The Virginia Institue of Marine Science estimated that in

2004 recreational and commercial fishing in the Bay contributed $1.23 billion in sales,

$717 million in income, and more than 13,000 jobs in Virginia alone. And there are

other benefits such as increased property value from cleaner waterways. One of the


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points of this paper is to draw a line of causation between these benefits and improved

stormwater management techniques and green infrastructure in the Chesapeake Bay

Region.

Green infrastructure has many positive implications, but according to the EPA, as

of Nov. 2013, the government was still looking for a database that would bring together

information on the effects of green infrastructure and stormwater management on

watershed health in specific regions. There is very little hard data with numbers like that

for specific regions. However, the rest of this paper will fill in that data for at least the

Chesapeake Bay region by looking at the literature on the health of the Chesapeake Bay

waters in the Gunston Cove watershed (mainly from green-infrastrured Fairfax County),

and the Upper Potomac River watershed (mainly from paved-over Montgomery County

and DC).

The following literature review will focus mainly on literature pertaining to

Gunston Cove and the Upper Potomac, and how their watersheds handle stormwater

management. It is meant to highlight items of interest and bring them together to

formulate a conclusion that perhaps has not yet been reached by others in the field.

Literature Review:

The first item under review is a press release by Raviya Ismail of Earthjustice

that discusses a court case where the Maryland Department of the Environment and

Montgomery County were sued by the Anacostia River Keeper organization, among

other petitioners, over the county’s lax approach to stormwater management. According

to the article, Montgomery County Circuit Court Judge Ronald B. Rubin ruled that a


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permit issued for the Montgomery County storm sewer system by the Maryland

Department of Environment was in violation of the Clean Water Act law, as it allowed

for too much pollution to be dumped into the Bay from Montgomery County. According

to the article, Montgomery County has a 499 square-mile storm water sewer system,

and according to the Maryland Department of Energy’s own report, Montgomery

County would have to reduce sediment discharge by 46%, nitrogen and phosphorous by

79%, and fecal bacteria by 96% or order to meet Maryland State requirements for water

quality.

The second item under review looks at the water quality of two different areas in

the Chesapeake Bay. The literature under review is the report, “The Ongoing Aquatic

Monitoring Program for the Gunston Cove Area of the Tidal Freshwater Potomac River ,”

by the Potomac Environmental Research and Education Center of George Mason

University under R. Christian Jones, final report published in September of 2013. The

report states that two stations in the Chesapeake Bay were monitored for water quality,

one in Gunston Cover (station 7) and one in the Upper Potomac (station 9). They

sampled for various elements at each station, but the most telling result was the amount

of nitrogen at each station, as the Gunston Cove Station had the smaller amount of

nitrogen than the Upper Potomac region. This particular literature is lacking a

conclusion as to why this was the case.

Through further research it was found on the fairfaxcounty.gov webpage that the

main tributary into Gunston Cover is the Accotink Creek, and that the Accotink Creek

Watershed is within Fairfax County, and that it encompasses the City of Fairfax.

According to fairfaxcounty.gov, the county has implemented no less than 5 green


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stormwater management initiatives since January 2014, including restoration of river

and stream banks, and the creation of wetland environments in stormwater

management facilities. Also, according to Stephanie Kupka, the Sustainability

Coordinator for the City of Fairfax, the city is dedicated to outreach to the public about

the importance of proper stormwater management techniques like installing rain-

barrels and permeable pavement, and they have a strong campaign to fight citizens’

water pollution with no-dumping signs near many storm drains and sewers.

Findings:

A number of factors need to be considered to come to a conclusion from this

information, including the fact that Fairfax city and county have such strong green

infrastructure and stormwater management plans, and that Montgomery County is

doing so poorly on its measure of stormwater sustainability. Also one must considers the

location of the two sampling sites (site 7 in Gunston Cove, the let out of Accotink Creek

running through Fairfax, and site 9 in the Upper Potomac, a point north where

Montgomery County’s water flows through), and what the results were of those

samplings (that Gunston Cove has less Nitrogen than the Upper Potomac). With all this

information, it can be at least hypothesized, if not concluded, that the installation of

green infrastructure has a positive impact on the levels of nitrogen in the waters of the

Chesapeake Bay. One might argue that correlation does not mean causation, so further

research would need to be done to prove this conclusively, but this at least begins to fill

in the gaps of research into the value of green infrastructure in comparison to traditional

infrastructure on the health of an aquatic ecosystem.

Methodology:


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In order to reach my findings, I reviewed literature pertaining to stormwater

management techniques, water sampling, ecology, and economics, among others. The

literature came in the form of scientific water sampling reports, court documents, press

releases, and government and non-profit webpages and documents. I conducted all of

my research through online searches, including library/academic search engines,

government and non-profit webpage searches, and through google searches. To

compare the nitrogen levels in Gunston Cove vs. the Upper Potomac, I looked at the

various nitrogen-sampling charts in the article, “The Ongoing Aquatic Monitoring

Program for the Gunston Cove Area of the Tidal Freshwater Potomac River,” and

compared the two levels, and each time the Upper Potomac had more Nitrogen levels.

Conclusion:

The Chesapeake Bay is a precious resource, whether because of the financial

gains to the area due to public recreation in its waters, or because of its biodiversity, or

simply for its beauty; the Chesapeake Bay is a treasure to America. But this resource is

threatened from pollution and sediment from overdevelopment and outdated

stormwater management techniques. But citizens can do their part to help alleviate this

situation by installing green infrastructure, such as rain barrels, permeable walkways,

and rain gardens, and by demanding that the government install green infrastructure in

their municipalities as well, through green roofs and permeable pavement roads and

parking lots. Much can be done to help the Bay, and many municipalities are already

well on the way to becoming green cities, including Fairfax, VA, but more must be done

in order to continue to restore the Bay to a clean and un-impaired waterway.


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Works Cited

Brouwer, Abraham, et.al. “Characterization of Potential Endocrine-Related Health

Effects at Low-Dose Levels of Exposure to PCBs.” Environmental Health

Perspectives 107.4 (1999): 1. Web. 12 May 2014.

Chesapeake Bay Foundation. CBF, 2014. Web. 29 Apr 2014.

Chesapeake Bay Foundation. “Polluted Runoff: How Investing in Runoff Pollution

Control Systems Improves the Chesapeake Bay Region’s Ecology, Economy, and

Health.” CBF. Jan 2014. Web. 29 Apr 2014.

Chesapeake Bay Foundation. “What is the “Value” of the Chesapeake Bay and Virginia’s

Waterways?” CBF. 10 Apr 2014. Web. 29 Apr 2014.

Chesapeake Bay Program. “Polluted Runoff Is Increasing in the Chesapeake Day

Watershed.” Chesapeake Bay Program 2011 Model. Chart. Web. 29 Apr 2014.

EPA. Environmental Protection Agency, 2014. Web. 12 May 2014.

EPA. “Using Smart Growth Strategies to Create More Resilient Communities in the

Washington, D.C. Region.” Nov 2013. Web. Apr 29 2014.

http://www.epa.gov/smartgrowth/pdf/mwcog-guidebook-final-508-111313.pdf

http://www.epa.gov/smartgrowth/pdf/mwcog-guidebook-final-508-111313.pdf


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Fairfax County Virginia. “Stormwater Projects Under Construction.” 2013. Web. 13 May

2014. http://www.fairfaxcounty.gov/dpwes/construction/bids/stw_current.htm

Green City Clean Waters. Philadelphia Water Department. Film. Web. 18 Apr 2014.

www.phillywatersheds.org

Ismail, Raviya. “Montgomery County Circuit Court Judge Sends Stormwater Permit

Back to Maryland Department of Environment.” Earthjustice.com. Earthjustice,

21 Nov 2013. Web. 13 May 2014.

Jones, R. Christian & Kim de Mutsert. “The Ongoing Aquatic Monitoring Program for

the Gunston Cove Area of the Tidal Freshwater Potomac River.” Potomac

Environmental Research and Education Center - George Mason University. 2013.

Web. 10 May 2014.

Lancaster Green Infrastructure Plan. Saveitlancaster.org. Youtube.com. Natural Light

Films, Inc, 2012. Film. Web. 29 Apr 2014.

National Wildlife Federation. “Chesapeake Bay,” 2014. NWF. Web. 29 Apr 2014.

U.S. Fish and Wildlife Service – Chesapeake Bay Field Office. “Federally Listed

Endangered and Threatened Species – Maryland.” 28 Jan 2011. Web. 1 May

2014.

Virginia Department of Health. Virginia.gov, 29 Mar 2013. Web. 13 May 2014.

http://www.fairfaxcounty.gov/dpwes/construction/bids/stw_current.htm

http://www.phillywatersheds.org/

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