Green Infrastructure Practice – Overview of Green Infrastructure and descriptions of various practices.
Technical Analysis of Green Infrastructure – Analysis of the CSS area with respect to green roofs, three kinds of infiltration practices, tree planting, and rainfall harvesting (cisterns and rain barrels) and its potential impacts on the CSS.
Green Infrastructure Projects – Brief overview of the preliminary design concepts for six projects.
Green Infrastructure Incentives and Financing – Summary of various potentially applicable incentive practices that have been applied in other cities to encourage the use of Green Infrastructure.
Click here to download the entire plan in PDF format
I know this video has been out a while (since 2007). I recently ran across it again on Youtube and thought it would be worth sharing. The video is a 90-second public service commercial that promotes urban rainwater harvesting in India. It was created for/or by The Centre for Science and Environment (CSE), a public interest research and advocacy organisation based in New Delhi. It is a simple but powerful message. Enjoy.
Staying with the Olympic theme from last week’s post on the Vancouver Convention Centre, the Southeast False Creek Olympic Village is another spectacular example of sustainable building in Vancouver. The Olympic Village will house the athletes throughout the games. Afterward, it will become the home of over 16,000 residents. The following is a link to the diversity of uses that will be or are already included in the development.
A website called “The Challenge Series” has been set up to help educate the public about the Olympic Village’s sustainable features. A well-designed booklet describing the sustainable features of the development is available on the site in pdf format. One that particularly caught my attention was the Water + Building Landscape section (See Cover Above). It explains many sustainable water strategies employed throughout. Some highlights include:
The design team recognized the size was not large enough to handle all of the stormwater in the constructed wetland incorporated into Hinge Park. As a result, the team prioritized the water into a two-tier system. The first tier was considered the “cleaner” water that came from the rooftops and podium sections of the building. This water was directed to the cisterns in the basements of each building. The water was then used to flush toilets, supply water features, or irrigate the landscape. Additional water overflowed the cisterns and entered the South False Creek. The second tier included “dirtier” water. This water came from the roadways and other areas. The water from these areas was directed into the constructed wetland or underground gravel/sand infiltration cells.
The development reduced potable water use by 40 percent.
The site plan incorporates a number of water features that utilize the water collected on the site. The circulation through the water features provides a means of making what would otherwise be invisible visible, while at the same time improving the quality of the water.
287,000 s.f. of green roof covers the development. The roofs include both extensive and intensive green roofs. This was in part because the City of Vancouver mandated that 50% of the roofs be green roofs.
The City also mandated the inclusion of urban agriculture at a rate of 24sf for 30% of the units whose balconies were less than 100sf.
The development has received LEED-ND Platinum certification. I look forward to seeing it one day when I return to Vancouver. There have been a number of articles on the development, but I highly recommend reading the information found on The Challenge Series website.
The winter Olympics just kicked off with the opening ceremonies from BC Place Stadium in Vancouver. But serving as the International Broadcasting hub for the games is the Vancouver Convention Centre— the world’s first LEED Canada Platinum rated convention building. The 1.2 million SF center boasts a 6-acre green roof, which also now makes it the largest green roof in North America.
The roof is planted with over 400,000 native plants and collects rainwater for irrigation which contributes to the buildings stormwater credits as well. Other interesting sustainable features include marine and shoreline habitat restoration. Fish habitat was actually built into the buildings foundations. The building also uses seawater for heating and cooling and incorporates on-site water treatment.
The following video “Vancouver’s 6 Acre Living Green Roof”, posted on You Tube gives a great sense of the scale and context of the green roof. The landscape architect who worked on the project, Bruce Hemstock, discusses the plants used, soil media and the idea behind habitat linking into urban centers that is beginning to be made possible with the inclusion of more green roof in our cities. Interestingly enough he says one of the biggest challenges of the project was initially convincing people that it was the right thing to do.
How much water can you harvest from fog? I hadn’t really thought about it until, I recently came across the work of FogQuest. FogQuest is a small Canadian all-volunteer organization founded in 2000 that constructs fog collection systems in areas where conventional sources such as wells, rivers and pipelines are not available.
While not as applicable in most of the United States as a primary source of water harvesting (where we use approximately 100gals of water per person per day), the technology is still fascinating and has been effective in developing countries. The system is comprised of a series of screens made of polyethylene or polypropylene erected on poles in areas that frequently experience fog events. According to FogQuest’s website, a 40m2 system can on average collect approximately 200L per day (53 gallons). Like rain harvesting, there are days where no water is harvested, but on some days the system has been reported to collect up to 1000L (264 gallons). FogQuest estimates that a 40m2 system cost between $1,000-$1,500. They have a number of videos on their site that describe the system in more detail (Link to Videos). Andrew R. Parker, a zoologist at the University of Oxford, and Chris R. Lawrence, an investigator at QinetiQ, have developed another fog collection technology based on the Namib Desert Beetle’s wings. They have been able to mimic the beetle’s process for collecting water. It is an interesting application of biomimicry. As the name suggest, the Namib Desert Beetle (see photo) lives in the Namib Desert where only a half-inch of rain falls annually. In response, the beetle has developed a unique survival mechanism. It is able to use its wings to collect water from fog that forms in the early morning and blows across the desert. The researchers discovered that this is accomplished through a series of small bumps on the surface of the beetle’s wings. When the beetle positions its body at 45 degrees the fog collects on its back and runs down the wings to its mouth. Here is a link to a website with more information about the process (link).
In places with high winds, it is thought that this new fog collecting material may be more efficient than the open polyethylene mesh used by FogQuest because the water cannot be blown through it. Other applications being considered for the material include using it to reclaim water vapor from cooling towers to developing tents that would capture fog for drinking water. This material has even been envisioned to reduce or eliminate fog that can disrupt transportation systems (i.e. airports, roads).
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.
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.
This year Kansas City embarked on a massive $2.3 billion stormwater overflow control plan to address sewer overflows throughout the city. Its inclusion of a major $28 million green infrastructure pilot project has gained a lot of attention. The project has been recognized as the largest green infrastructure project in the United States. The Marlborough Neighborhood Pilot Project, as it is called, is located in the Middle Blue River Basin, one of the four major watersheds addressed by the plan. The entire pilot project encompasses nearly 100 acres of primarily residential neighborhoods. This program is anticipated to be expanded over a larger 744 acre area that will eventually include over 25 acres of mixed green infrastructure strategies (i.e. rain gardens, bioswales, permeable pavement, and green roofs) that have the capacity to sequester 3.5 million gallons of water. The green infrastructure strategies employed are designed to replace two underground tanks of similar capacity. In total the pilot project and its expansion are budgeted to cost $68 million.
Video of compiled images from Mark O’Hara’s Greenbuild Presentation about the Kansas City Plan. The video shows various Green Infrastructure Strategies recommended in the plan. Video compiled by Hawkins Partners Images provided by BNIM (Click here to see it if video is not present)
In addition to the Marlborough Neighborhood Pilot Project, the plan also recommends the enhancement of the area’s highly acclaimed 10,000 Rain Garden Program. Over the past two years, the initiative is reported to have installed several hundred rain gardens, bioswales, and rain barrels. The purpose of the expansion it to develop an incentive program to accelerate the program’s progress and complement the public investments being made.
Wet retention basin projects have been identified as an appropriate strategy for treating stormwater downstream from six separated sewer system (SSS). The plan acknowledges that green infrastructure is beneficial and should be included where it is practical. The plan states:
“Every decision should be viewed as an opportunity to incorporate a green-solutions approach. The City has adopted an “every drop counts” philosophy, meaning it is important to reduce stormwater entering the system wherever practicable. This will be accomplished through changing the way the community develops and redevelops its sewer and stormwater infrastructure, educating citizens regarding steps they can take to reduce the amount of stormwater entering the sewer system, enabling citizens to take those steps, incorporating green infrastructure in the design of public infrastructure, and making targeted public investments in green infrastructure projects early in the Plan implementation.”
Areas identified that should be considered for green infrastructure projects include those meeting the following criteria:
Areas for which no or minimal conventional structural controls are proposed.
Areas in which widespread implementation of green solutions by the community at large offer the greatest opportunities for reducing the size and cost of conventional structural controls included in the Plan.
Areas for which it would be particularly desirable to further reduce the projected overflow
activation frequency following completion of recommended controls.
Areas in which sewer separation is proposed but where no Water Services Department (WSD) investment in treating the separate stormwater runoff has been included in the Plan.
The plan’s ambitious Marlborough Neighborhood Pilot Project is very encouraging, particularly as a stand alone project. It is very significant and the City should be commended for their efforts. However based on the $2.3 billion budget established by the plan, it is evident that green infrastructure will play a supporting role. The plan was developed during the recent significant shift in the way we address stormwater management across the country over the last few years. It is not surprise to see this. What is encouraging is the magnitude of the pilot project and the extensive monitoring that will be conducted.
The monitoring component will provide valuable data for the City and others across the country. In addition to understanding green infrastructure’s effectiveness to control Combined Sewer Overflows (CSOs) and improving water quality, monitoring it will provide insight into conflicts with local codes and ordinance, social-economic benefits, construction techniques, associated cost, and maintenance practices.
The plan stresses that it is an evolutionary document, referring to it as an “adaptive management” approach. The approach involves evaluation of the strategy throughout the life of the project based on their experiences and data gathered through the monitoring efforts. While green infrastructure may not be the predominant tool of choice at this point, the longer-term nature of the plan provides the opportunity to adjust its course as confidence increases in green infrastructure. The City’s plan can become more green overtime as it builds upon its successes.
Fairly or unfairly, like many pilot projects much rests on the success of the Marlborough Neighborhood Pilot Project. Many, both locally and nationally will be watching it with great interest. Failure of such a high profile project could significantly set back the growth of green infrastructure as the stormwater management tool of choice. Therefore, it is critical it is done to the highest standards possible. The project will serve as an example for those involved in stormwater planning and design to have full confidence and understanding of the complexities of utilizing natural systems. Natural processes are complex making them more difficult to quantify. A paper prepared in 2007 by the Center for Neighborhood Technology titled “Managing Urban Stormwater with Green Infrastructure: Case Studies of Five U.S. Local Governments”, identified the lack of performance data as a barrier to green infrastructure implementation. The more research we do and data we collect the better off we will all be.
I anticipate this will be a successful demonstration of green infrastructure. It is exciting to see another city embrace green infrastructure on such a large scale. We will all eagerly await the results and follow its realization. Construction is expected to start soon.
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.
The recent transformation of Deaderick Street recalls the historic importance of the street and enhance the corridor’s prominence as an important civic axis. Prior to the renovations, the street had become most widely known as the central transfer point for the Metro bus system. In the Fall of 2008 the bus system’s hub was relocated one block over to the ambitious Music City Central, presenting an opportunity to re-envision the street itself
The renovations to the street primarily focused on addressing stormwater issues and urban trees. The existing streetscape was home to an assortment of unhealthy trees ranging in sizes from 2” caliper up to 24”+. Each and every one of them were shoehorned into a 4’x4’ planting zone and struggling to adapt to urban conditions. The renovations included removing those trees and providing larger and deeper planting areas that would not only give a larger volume of soil for the tree roots, but also provide many areas in which the stormwater could travel to, thus reducing the loads into the storm system. Bioretention zones were implemented in pedestrian bulbs at the intersections and in relation to the existing catch basins. These planting areas were also excavated to a depth that would accept enough engineered soils to allow infiltration and planted with plants that can adapt to the extremes of wet and dry conditions. Pervious area within the corridor was increased by over 700%.
Many other elements of sustainability were included, such as:
Crushed and recycled concrete used for the pavement subbase,
Fly ash utilized in the concrete mix,
Porous concrete,
LED light fixtures,
Native and drought tolerant plant materials,
Solar powered parking meters,
Water efficient irrigation system,
Many local vendors and fabricators,
The addition of bike racks to help encourage a healthier way to travel, and
The addition of recycling receptacles along the street.
We’re hoping that in the near future, permanent retail kiosks that were proposed in the master plan will be added to the street, further enlivening the corridor. Those kiosks are proposed to have an extensive greenroof on each. In addition, the master plan identified areas for future free standing retail buildings and liner buildings that could be added on the blank facades.
Source: 
Streetscape
Underground Rainwater Harvesting Tanks
No Curbs with Filter Strips
Green Infrastructure Digest 
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