A NEW MEANING TO THE COLLEGE “GREEN”

18 12 2009

Green Roof Dashboard
from Davis Center at University of Vermont

With a son who is a sophomore in college and a daughter as a high school senior, I have managed to spend a lot of time visiting college campuses over the past few years. One of the things that I have paid particular attention to (and seen an huge increase in during the past two years) is the focus on sustainability. My strong hunch is that schools are incorporating sustainable technologies because this generation of smart, college age youth demand it.

Many college campuses now sport LEED certification on at least one building – my son’s dorm at the University of Richmond (Lakeview Hall) is LEED registered and undergoing certification. It is one of nine buildings at the University which is either certified, or in process of being certified as LEED with the USGBC. Locally, Vanderbilt University completed the LEED certified The Commons at Vanderbilt residential housing complex in 2008. As I have traversed the country and seen what must be dozens of (mostly) smaller liberal arts colleges, I have seen organic gardens and solar panels at Whitman College, windmills and biomass generators at Middlebury, local and organic foods at Skidmore, a unique “homestead” intentional environmental community at Denison, beautiful rain gardens at Emory and the list goes on.

I also found a interesting resource online called the College Sustainability Report Card for 2010 (www.greenreportcard.org), This report card basically looks at environmental sustainability at over 325 colleges and universities in the United States and Canada based on 48 indicators used to evaluate performance within four categories.

One of those categories is “green building”. It was heartening to see that 44% of the schools have had at least one LEED-certified green building or are in process of constructing one and a whopping three-quarters of all of the schools have adopted green building policies that specify minimum performance levels such as LEED certification for new construction.

I was particularly interested in taking a closer look at some of the successes that I have witnessed at several of the schools that I have visited especially as they relate to green infrastructure. I found some additional information on Emory, Allegheny, Middlebury, University of Vermont and Macalester.

WATER CONSERVATION

As a part of Emory University in Atlanta’s overall commitment to sustainability (with over 1 million square feet in LEED certified buildings), Emory has incorporated many innovative water-conservation technologies.. Particularly impressive to me was their implementation of rainwater harvesting and condensate recovery, especially in light of the fact that Atlanta suffered an historic drought event in the summer of 2007. On Emory’s whole campus they have to date included 6 cisterns with a collective size of over 350,000 gallons for both toilet flushing and for irrigation as well as a condensate recovery technology for over 4 million gallons of water per year.

In their new freshman residence complex including Ignatius Few Hall and Lettie Pate Whitehead Evans Hall, rainwater and condensate collection is diverted to an 89,000 gallon reservoir underground which can provide adequate volume to provide 2170 gallons per day needed to flush all toilets int eh buildings. The rainwater is collected form the roof, then filtered and slowed through a bioswale system outsde of the building and then into the below grade cistern. The condensate harvest provides a reliable source of water to supplement rainfall during those months from May through September. It is estimated that the condensate harvests is adding 300,000 gallons per year to the system.

At the nearby Whitehead Biomedical Research Facility Building, completed in 2001, the engineers devised a system of piping condensate back into nearby cooling towers to use as make-up water. This system conserves water AND diverts 2.5 million (that’s 2,500,000) gallons a year from the sanitary sewer system.

Video About Emory University’s Sustainability Efforts

GREEN ROOFS

It seems to me that many, many schools are incorporating green roofs as that technology provides one of the most visible elements to show-off sustainable design. In every school we visited, if there WAS a green roof, it was highlighted on the student led campus tours. The green roof were touted for their well-documented benefits such as longer roof life, reduced cost of heating and cooling, stormwater runoff reduction and habitat.

Allegheny College in Meadville, Pennsylvania impressed me with the well designed green roof on the Vukovich Center for Communication Arts. It is located within the topography of the campus site allowing for a fully accessible roof (entering the building at the green roof on the high side and entering on a lower level to the main campus commons or quad –type area. The roof includes extensive and semi-intensive depths and features lawn space as well as sedums and native grasses with an interesting incorporation of stones and cedar decking through the rooftop.

University of Vermont, just on the edge of downtown Burlington, Vermont, recently completed the 186,000 s.f. Dudley H. Davis Center. The Center features a 19,000 s.f. green roof.

Middlebury College, also in Vermont, provided a sloped green roof above the Atwater Dining Hall. I was interested in seeing their notation that in addition to the traditional green roof benefits that I have seen listed in may locations, Middlebury includes improved acoustical insulation, noting that green roof systems can reduce airborne sound levels by 40 to 50 decibels.

Macalester College in St. Paul, Minnesota impressed me, not in size but in determination. The two green roofs on campus were the result of student designs and even some student labor! The first green roof at Macalester was a 300 s.f. tray system installed above a walkway between tow residence halls and the newer 1350 s.f. green roof on Kagin Commons. I happened to be on campus the day the Kagin Commons green roof was unveiled.

I believe the influence of these campuses and so many others will influence the bright minds of our next generation of decision makers and leaders.


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Categories : Green roof, LEED, Sustainable Site Strategies, Uncategorized, Water Harvesting

Green Infrastructure for Clean Water Act of 2009

16 12 2009

Photo Credit: istockphoto/ericfoltz

On December 4th, Representatives Donna F. Edwards (D-MD), Russ Carnahan (D-MO), and Steve Driehaus (D-OH) introduced the Green Infrastructure for Clean Water Act of 2009 to Congress. The legislation is expected to be referred to the House Transportation and Infrastructure Water Resources & Environment Subcommittee, as well as the House Science and Technology Committee on which Edwards and Carnahan serve. The bill seeks to establish five research centers across the country. One of the centers will be designated as the national electronic clearinghouse that would develop, operate, and maintain an on-line resource for green infrastructure information. Each of center would be required to do the following (excerpt from bill):

(A) conduct research on green infrastructure that is relevant to the geographic region in which the center is located, including stormwater and sewer overflow reduction, other approaches to water resource enhancement, and other environmental, economic, and social benefits;

(B) develop manuals and set industry standards on best management practices relating to State, local, and commercial green infrastructure for use by State and local governments and the private sector;

(C) provide information about research conducted under subparagraph (A) and manuals produced under subparagraph (B) to the national electronic clearinghouse center for publication on the Web site created pursuant to subsection (C) to inform the Federal Government and State and local governments and the private sector about green infrastructure;

(D) provide technical assistance to State and local governments to assist with green infrastructure projects;

(E) collaborate with institutions of higher education and private and public organizations in the geographic region in which the center is located on green infrastructure research and technical assistance projects;

(F) assist institutions of higher education, secondary schools, and vocational schools to develop green infrastructure curricula;

(G) provide training about green infrastructure to institutions of higher education and professional schools;

(H) evaluate regulatory and policy issues about green infrastructure; and

(I) coordinate with the other centers to avoid duplication of efforts.

In addition, the bill would create a $300 million grant program that could be used for planning, development, and implementation. As much as $100 million could be given to selected planning and development initiatives and a total of $200 million would be designated for implementation projects. The cap for individual projects would be $200,000 for planning and development projects and $3 million for implementation.

As this bill progresses, we will keep you up-to-date.

-Brian Phelps


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Sustainability Resource Guides from ASLA

14 12 2009

The website for ASLA (American Society of Landscape Architects) has a fairly new section devoted to resources for sustainable design and planning. If you haven’t wandered across it already you should take a minute to see what it has to offer. It is aimed at national and local policymakers, government agencies, design professionals, planners and students. Resources include hundreds of project case studies, research papers, organizations and other government resources on sustainable design.

The following description of the five resource categories is taken from an announcement by ASLA, they include:

  • Green Infrastructure (www.asla.org/greeninfrastructure) covers park systems, wildlife habitat and corridors, urban forestry and green roofs.
  • Sustainable Transportation (www.asla.org/sustainabletransport) covers sustainable transportation planning, siting sustainable transportation infrastructure, designing safe and visually appealing transportation infrastructure, green streets and reducing the urban heat island effect.
  • Sustainable Urban Development (www.asla.org/sustainableurban) covers fighting sprawl, sustainable zoning, reusing brownfields, investing in downtowns, open spaces and sustainable urban design.
  • Livable Communities (www.asla.org/livable) covers sustainable land use, place making, green schools, sustainable housing, sustainable employment growth and health, safety and security.
  • Combating Climate Change with Landscape Architecture (www.asla.org/climatechange) covers site planning, open spaces, plant selection, stormwater management and other areas.

While the site is a little hard to navigate, (if you like what you see, I suggest you bookmark the above links to be able to find them again) this is a good resource that pulls a lot of varied information together into one area. It has potential to be not only helpful for designers, planners and people who speak the sustainability language, but also to be useful to vastly wider audience. I understand they are also always looking for new projects, research, case studies, etc. to highlight, if you want to contribute you can contact ASLA @ info@alsa.org

-Sara Putney


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Tennessee Ranks in the bottom ten…again

2 12 2009

In the list of healthiest and least healthiest states releases from Forbes this month the southern region of the country is once again lagging behind. All in all eight of the bottom 10 were states from the south, including Tennessee which ranked number 44 overall and number 49 in obesity.

Why does this relate to green infrastructure you might ask? There are in fact many ways to relate green infrastructure to our health. (Check out the numbers from the earlier post ‘Triple Bottom Line of Green Infrastructure) Some are the obvious reasons such as cleaner streams and rivers, cleaner air, etc, that often create a more desirable environment to become engaged in and interact both physically and socially. But take a step back and consider green infrastructure planning; in brief planning amongst, preserving and restoring our natural infrastructure systems, such as river corridors, woodland networks and open spaces. This type of planning allows us to integrate greenway trails, bikeways and neighborhood trails into our built environment in a responsible way. The more access communities have to resources such as these allows them more opportunities to get the recommended 30 minutes of physical activity per day, increasing the overall heath of the community. There is a strong link between lack of physical activity and chronic diseases such as heart disease and diabetes.

Other more indirect regional health benefits stem from increasing the amount of land for natural storm water retention which in turns allows communities to become more resistant to natural disasters. Green infrastructure also can reduce the erosion of precious top soil, which aids local farms. The entire region benefits when a collection of local farms can provide healthy food. Working farms—and forests—also have a significant impact on local economies by providing jobs, aiding tourism and supporting local manufacturing.

So in the end, green infrastructure benefits extend beyond immediate storm water benefits and reducing our carbon footprint. By integrating the green infrastructure planning principles we can also provide opportunities to make our communities healthier, reduce overall healthcare costs and hopefully move Tennessee up in the ranks of healthiest states.

-Sara Putney

Shelby Bottoms Greenway in the Cumberland River Corridor


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Opportunity Delayed?

23 11 2009

Over the past decade, cities have utilized a variety of methods to encourage and/or require sustainable building practices within their jurisdictions. All across the country green building incentives were enacted. According to a recent AIA Survey, 138 cities have some form of green building programs. Methods that rely on density bonuses or tax increment financing to reward/incentivize developers were predicated on growth. Unfortunately, the building boom over the last three to five years has fizzled (for the time being at least). It is no secret the development landscape has changed. Obviously, fewer projects being built equals less opportunities to incorporate green infrastructure within our landscapes. This really isn’t a problem if a project was being built in a greenfield. In fact, on a number levels especially in regards to stormwater management and water quality, it is preferable. But for the greyfields and brownfield sites that comprise much of our urban landscape, it is opportunity delayed. The opportunity being to convert these sites to better use and mitigate their negative impact. The old parking lots and retail centers continue to absorb and radiate heat while directing polluted stormwater into overburdened infrastructure and streams. This is particularly acute in areas that were built prior to modern stormwater standards.

So what are cities doing to encourage the incorporation of green infrastructure under these new market realities?

Stormwater Fees. Realizing that general funds can no longer meet the demands imposed on cities by the Federal Government and State Agencies, many cities have or are relying heavily on stormwater fees. Typically these fees are applied to everyone’s property based on impervious surfaces. It is common under these programs for property owners to receive discounts through the use of various stormwater management strategies. These often include green infrastructure related tools (i.e. green roofs, bioretention areas, pervious pavements). Depending on the significance of the fees, this can be a deciding factor for property owners to retrofit their properties. However, in most cases they are not high enough to warrant major investments.

Dedicated Funding. The City of Portland has taken a page from the art world and have enacted a “One Percent for Green” program that works similar to the more common “Percent for Art” programs. It is funded by allocating one percent of the city’s construction budget for the purpose of building green streets both on public and private property as long as it treats public stormwater. It also includes any new and retrofit projects that wouldn’t trigger the Stormwater Management Manual.

Economy of Scale. The unique double functioning nature and triple bottom line benefits of green infrastructure has prompted cities to combine stormwater management with other projects such as parks, streetscapes, road improvements, and other capital projects. The economy of scale allows them to stretch their dollars further to meet the needs of the city.

Direct Reimbursement. As mentioned in an earlier post about Chicago’s green roof program, cities are offering direct reimbursement of installing green infrastructure. This has manifested itself mainly for constructing green roofs. These reimbursements typically run around $5 per sf. Depending on the situation this can reduce the square foot cost for a green roof by as much as 30%.

Clean Water State Revolving Fund (CWSRF). CWSR Funds are another useful tool offered by each individual state that municipalities are utilizing to fund green infrastructure projects. Funding is provided by a combination of EPA grants and State matching funds. The basic premise is the fund provides low interest loans to municipalities for wastewater treatment, stormwater management, nonpoint source abatement and estuary protection projects. The payments toward the loan are reincorporated back into the fund where they can be loaned again. This method is increasingly becoming popular as a means of implementing green infrastructure projects across the country. The 2009 Stimulus Plan (American Recovery and Reinvestment Act, ARRA) gave a considerable boost to these programs. It includes $4 billion for Clean Water State Revolving Fund projects and $2 billion for Drinking Water State Revolving Fund projects.

Together programs like these have enabled municipalities to continue investment in their stormwater infrastructure. As cities grapple with the current market conditions, we should expect to see new creative funding ideas and a continued commitment toward increasing the use of green infrastructure throughout our cities.

-Brian Phelps


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Hill Center Green Hills receives Middle Tennessee ASLA Honor Award

20 11 2009

Streetscape

Underground Rainwater Harvesting Tanks

No Curbs with Filter Strips

The Middle Tennessee Chapter of the American Society of Landscape Architecture recently presented Hawkins Partners, Inc. a 2009 Honor Award in the environmental/urban design category for its work on the Hill Center in Green Hills.

Hollie Cummings, executive director of ASLA Tennessee Chapter, was quoted in an article in the Tennessean (Hill Center wins architecture award for urban design) saying, “The jury appreciated the use of details that served to unify the development and resulted in a cohesive design solution.”

HPI was involved in the planning, design, and construction of this infill redevelopment project located in Green Hills. The 220,000 s.f. mixed-use development consists of retail, restaurant, and office space. Site design elements include a pedestrian activated streetscape, which consists of wide sidewalks for shoppers, places for people to sit and relax or visit with friends, and outdoor dining along a tree-lined boulevard.

Sustainability played a big role in the design process. HPI collaborated with the design team to provide 100% improvement in the stormwater treatment over the previous site conditions. The site captures rainwater in a 25,000 gallon underground tank for use in irrigating the landscape (comprised primarily of native plants), and also utilizes new bioretention areas, which slow and reduce runoff – ultimately helping lower the temperature of runoff into the nearby Sugartree Creek. Some other items include a white roof on the Whole Foods store, over 60% of the parking is provided by covered structures and all the site lighting utilizes cut-off luminaires to reduce light pollution.

This project also won the Excellence in Development Award presented by Urban Land Institute (ULI).

– Kelly Copeland


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Chicago Green Roofs: Seven Million Square Feet and Growing

13 11 2009

green_roof_sedum

I got the chance to spend a little bit of time last week with Chicago’s firecracker Commissioner of Environment, Suzanne Malec-McKenna while she was in Nashville for the Nashville Civic Design Centers annual Plan of Nashville event. Suzanne has been in the middle of an astonishing number of Chicago’s environmental bright spots, including the ambitious Chicago Climate Action Plan released in 2008, Chicago Trees Initiative and the very cool Chicago Offset Fund. But what has impressed me the most (and has for a long time) is Chicago’s tremendous growth in green roofs.

It all started in 2001 with the now well-known Chicago City Hall roof weighing in at a modest 20,000 s.f. In June 2008, a short seven years later, Chicago boasted 4,000,000 s.f. of green roof and today, they report that they have hit 7 million s.f. and they are still going. I wanted to find out more about how such an explosion occurs and one of the pieces and parts is related to the success of the green roofs is a Green Roof Grant Program begun in 2005 which has been continued and expanded. An interesting side note is that the popularity and volume of the green roofs across Chicago has also reduced the average installation price of extensive green roof in Chicago has dropped from $25/s.f. to $15/s.f.

As if the incentives of grant incentives aren’t enough, I also noticed that in August 2009, the Illinois Energy Plan provides ARRA funds toward cost-effective energy projects, including green roofs, which meet certain criteria. Illinois has recognized that green roofs provide economic development, carbon capture and energy and maintenance cost savings.

As I looked around at other cities, I found a few more that were engaged in similar incentive programs introduced within the last year: Portland, New York City and Washington DC (List of green roof incentive programs) . Through tax abatement or grants, each of these cities provide an incentive of about $5.00 per square foot through a green roof review process. Portland expects their Grey to Green Program to their current nine acres of green roofs on about 90 buildings to increase over the next five years by another 43 acres. Portland is committing $300,000 in grants in its first fiscal year of the program and is committed to keeping the program going for at least the next five years.

In our neighbor to the north, Toronto started the green roof incentives in 2006 starting with a $10 per square meter subsidy, then raised the subsidy amount to $50 per square meter in order to be more effective. Reports are that funding of $2.4 million dollars for green roof subsidies have been approved for the first five years of the program.

So hats off, Chicago! You are serving as a great example for the rest of North America – in fact, Chicago topped the Green Roofs for Healthy Cities list of top ten cities for both the United States and North America for the past five years.

-Kim Hawkins


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Making Green Infrastructure Common Place

6 11 2009

Philly_Green_City1

Getting more for less is an approach almost everyone can appreciate. Why wouldn’t you want to get the most out of your investments? Appropriately applying green infrastructure in ways that effectively addresses critical stormwater issues while creating a more beautiful and economically vibrant community is common sense. Unfortunately, it isn’t common place. As the use of the available sustainable site tools and technologies continues to grow, it may not be long before green infrastructure is the conventional approach to stormwater management.

With the Release of their “Green Cities Clean Waters Plan”, Philadelphia joins a handful of cities across the Country that have committed to green infrastructure and seek to institutionalizing it throughout the city. Philadelphia’s plan published last September sets forth a bold plan to invest $1.6 billion. Of this total 62% ($1 billion) of it will allocated directly to green stormwater infrastructure. Another 18% ($290M) will directed to stream corridor restoration and preservation and 20%($320M) will address wet weather treatment plant upgrades.

Over the next few weeks we will take a closer look at Philadelphia’s plan. At over 3,000 pages, there is a lot of information to sift through. In addition, we will also look at Pennsylvania Environmental Council released a report titled “Implementing Green Infrastructure: Developing a Winning Strategy to Fund Philadelphia’s Ambitious Plan” that looks at the economic benefits of the plan and how other cities across the country are funding their stormwater initiatives. Together they are an impressive step forward for the City of Philadelphia and the Nation.

-Brian Phelps


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A Different Kind of Green Roof

4 11 2009

Research has begun on a light weight alternative to extensive green roofs (the least intense form of a green roof) for when structural loads or costs might otherwise deter a client from choosing to pursue a green roof. It is being referred to as a ‘green cloak’ and uses fast growing vine species that attach to a trellis suspended above the roof. Laura Schumann, a graduate student at the University of Maryland completed her thesis on the cost benefits for temperature and stormwater using green cloaks. More complete information on temperature and stormwater reduction can be found on the University’s website.

While green cloaks will likely never provide near the benefits of an actual green roof system, a major potential is that they are probably a less expensive option when installing a green roof is just too cost prohibitive and a client is still looking for a way to save on energy costs. In addition to reducing cooling costs and slowing the runoff of stormwater from roofs, one of the most intriguing facets may be the potential for using vine and trellis systems on sloped roofs where it is currently challenging to implement traditional green roof systems. Another aspect is that vines have the potential to provide cover for vertical surfaces and may help provide even greater temperature benefits when combined to cloak walls as well.

The vine species researched in the study included 5 different species: cross vine (Bignonia capreolata), kudzu (Pueraria lobata), Japanese Honeysuckle (Lonicera japonica), porcelain berry (Ampelopsis brevipedunculata), and Virginia creeper (Parthenocissus quinquefolia).

Virginia Creeper

Testing Virgina Creeper's effects on Building Temperature (Photo from Univerisity of Maryland's website)

One drawback may be that green cloaks might not be as aesthetically pleasing to the masses as green roofs and could be a hard sell for more refined urban or retail areas. And it may also be difficult to provide full coverage for large roofs, however even partial coverage could provide huge cost savings in cooling costs for big box retailers or manufacturer’s with large warehouses where load bearing capacities for roofs are low and aesthetics are not as much of a concern. Either way, this is another potential option available for designers to help reduce energy costs, the urban heat island, and reduce stormwater runoff.

– Sara Putney

GreenCloakTilley.ppt

Inspiration (photo from 'Green Cloak' Presentation, David R. Tilley, University of Maryland)


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Green Roofs Address D.C.’s Environmental Problems

30 10 2009

asla green roofPhoto Source: ASLA

It has been three years since the American Society of Landscape Architects (ASLA) finished the 3,000sf green roof on top of the their headquarters building in Washington D.C. The green roof is unusual in that it is sloped to cover the mechanical units on the roof. An informative video (link to video) was posted on Youtube this month highlighting the stormwater benefits of the ASLA roof. Nancy Somerville, ASLA’s CEO was interviewed during the video and she stressed the important role green roofs could play in helping address Washington D.C.’s and the nation’s difficult stormwater issues (i.e. water pollution, Combined Sewer Overflows). An EPA report estimated 850 billion gallons of untreated sewage and stormwater are discharged nationally each year as combined sewer overflows. (EPA Fact Sheet [pdf]) As Ms. Somerville points out, green roofs can filter the stormwater falling on the roof as well as act as a sponge and significantly reduce the amount of stormwater coming off of the roof. A green roof with 4″ deep planting media has been shown to retain 63% of the rain fall hitting the roof.

During the first year, ASLA conducted a study (link to ASLA green roof website) to quantify the specific benefits of the their green roof. The data showed that 74% of the water was retained on the roof. Interestingly, the water quality of the stormwater discharge leaving the roof included an increase in pH and temperature as compared to the rain fall. In addition, the test results showed a significant increase over the concentration originally present in rain water for Chemical Oxygen Demand (COD), phosphate, total phosphorus, total suspended solids, and total dissolved solids. According to the report most of these contaminants were within the allowed freshwater chronic concentration values established by the E.P.A. and none of the concentrations were above the acute level. Unfortunately, the study did not compare the green roof with a conventional roof. The report concluded that “Green roofs have significant potential for reducing stormwater carried pollutants in major metropolitan areas such as Washington DC. However, more comprehensive and extensive monitoring studies are needed to evaluate specific performance measures of specific designs and develop accurate predictive tools.” The following are a few specific findings highlighted in their press release (.doc):

  • The roof typically retained 100 percent of a one-inch rainfall.
  • The heaviest rainfall during the monitored period was March 16, 2007. A total of 2.48 inches of rain fell during the 24-hour period with the roof retaining 51 percent, the equivalent of 1.3 inches of rain.
  • The green roof did not add any nitrogen to the runoff. Because of the amount of water retained, the roof provided a significant reduction in the amount of nitrogen introduced back into the watershed.
  • Typical of “young” green roofs, the analysis showed higher amounts of some other nutrients such as phosphorus, as well as heavy metals in the runoff—all below EPA standards and below levels expected from street runoff. Based on other green roof research, nutrient levels are expected to decrease in a few years. The heavy metals may be coming from the roof materials or from settled particulate matter/pollutants.
  • It is important to note that this study did not look at runoff from a conventional roof compared to the green roof runoff—and the results would be expected to look different. Water quality testing will be repeated in two years to see how the results change over time with a goal of comparing the green roof runoff to conventional roof runoff.
  • The green roof has been as much as 32 degrees cooler than conventional black roofs on neighboring buildings.
  • Engineering analysis showed that the green roof created a 10 percent reduction in building energy use during winter months and negligible difference in the summer.

On a city wide level, the Casey Tree, a non-profit dedicated to restoring, enhancing and protecting the tree canopy of the Nation’s Capital, conducted a study (link to study) of the Washington D.C. area that examined the impact of green roofs and tree plantings. They concluded that if 55 million square feet of green roofs were installed throughout the Washington D.C. area, they would reduce the reduce CSO discharges by 435 million gallons or 19% each year.

These studies illustrate the effectiveness of including green infrastructure within the overall strategy for cleaning up our nation’s stormwater.

-Brian Phelps


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