Invasive Species in the News

15 01 2010

When we plan and design for projects, within our trade, we try to use native species whenever possible. This is especially important when designing green infrastructure projects that tie so closely to our natural resources, in particular our waterways. Oftentimes people wonder why this is so important and how can it really affect them anyway? Whether it’s plant materials or animals, all invasive species are eventually extremely damaging to our native ecosystems. And also extremely costly; “The UN Convention on Biological Diversity says the spread of invasives costs 1.4 trillion dollars a year globally in damages and control measures. The U.S. alone loses 138 billion dollars a year in the fight.”

Image from ‘The Dirt’ website.

In ASLA’s blog ‘The Dirt’, a recent posts highlights the efforts for the State of Michigan to protect Lake Michigan and the entire Great Lakes Region from the Asian Carp. Like all invasive species these fish take over an ecosystem by consuming resources that would otherwise be used by the native species. Michigan is suing the State of Illinois in order that they shut down the waterways leading into Lake Michigan. According to the New York Times article Minnesota, Ohio, Wisconsin, and Indiana are all in support. This came to light due to recent evidence of the carp within 6 miles of Lake Michigan in the Chicago area waterway system that links the Mississippi River to the Great Lakes. And while the City of Chicago realizes that the carp overtaking Lake Michigan would be devastating they are wrestling with their own economic concerns over what closing the waterways would really mean. There is more detailed information in ‘The Dirt’ post and the New York Times Article.

Another item in the light recently is the efforts of the Chicago Botanic Garden and the Morton Arboretum to gather native seeds from around the Midwest. “Scientists from the botanic garden are sending teams out across the Midwest and West to the Rocky Mountains and Great Basin to collect seeds from different populations of 1,500 prairie species by 2010, and from 3,000 species by 2020. The goal is to preserve the species and, depending on changes in climate, perhaps even help species that generally grow near one another to migrate to a new range.” The idea is to catalogue, store and preserve native plants in the event that climate change or invasive species may require the migration of native plant materials to other areas. There is still much debate about the project and more detailed information can be found in the New York Times article.

These are just two examples in a long list of invasive species problems that continue to threaten the ecosystems of the US. Not only do invasives disrupt plants, animals and other natural resources, but as noted above they also can have huge negative economic impacts. This coming on the tails of National Invasive Species Awareness Week, (January 10-14th), to learn more visit the National Invasive Species Information Center’s website.

– Sara Putney


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Categories : Plans and studies, Sustainable Site Strategies, Uncategorized, water issues

Getting More: Multi-Functioning Facilities

13 01 2010

When it comes to adding more park space, communities are increasingly looking at getting more bang for their buck. Budgets are tight and cities are having to pool their resources from a variety of sources to get projects built. Two recent projects, one that is under construction in Los Angeles and another just announced in New York City, seek to create a park and nature area for their citizens while also constructing wetlands to address stormwater management issues within the immediate neighborhood and the community at-large.

The first is the South Los Angeles Wetland Park. The 9-acre park under construction five miles south of downtown Los Angeles on a former transit maintenance facility that is nearly 100% paved. The City recognized that more recreational open space was needed in the area while also needing to improve the quality of the stormwater runoff that ultimately was polluting the city’s beaches. The park transforms the site into a extensive wetland that comprises most of the park. It includes a series of trails, an observation area, and public gathering areas.

The park is estimated to cost $24 million. The funding was cobbled together from a variety of sources, including money generated from Proposition O. Proposition O passes in 2004, authorized the city to issue up to $500 million in bonds for cleaning up polluted storm water and bacteria in the City’s rivers, lakes, beaches and ocean. Stormwater Magazine has a thorough article about the genesis of the park and its design. Also, more detailed information can be found on Proposition O’s website.

South Los Angeles Wetland Park Site Prior to Construction
Source: Google Map

South Los Angeles Wetland Park Site Plan
Source: Proposition O Website

The second improvement is the Paerdegat Basin Restoration Project in New York City. The Department of Environmental Protection recently announced the $15 million project. It is anticipated to be completed by 2012. The park will restore 38 acres of wetlands and natural grassland areas adjacent to the $357 million Paerdegat Basin Combined Sewer Overflow (CSO) abatement project. Five acres will be dedicated as a Ecology Park that will be accessible by the public and offer educational opportunities. Funding for the project is provided by Clean Water State Revolving Funds. The combined projects are designed to store 50 million gallons of CSO during a storm event. (Press Release fro DEP)

Both of these projects serve as examples of how various communities’ goals can be combined and met by a single green infrastructure investment. As cities approach future planning and implementation efforts, they should look beyond the immediate objectives of the project and assess how the project might serve to address other needs that have been identified in the community.

-Brian Phelps


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Categories : Parks & Open Space, Sustainable Site Strategies

The Green Vs. Standard Showdown

11 01 2010

We do a lot of talking about green and trying to convince clients to do it. And then we wait for the question that will eventually come…….. so what’s the premium that I have to pay for that?

Not too long ago we had a client that took a big step. They commissioned us to have full schematic plans developed for their hospital site in North Carolina with both alternatives: green and conventional. The parameters, such as site area and number of parking spaces required, were the same. The conventional design used curb and gutter, catch basins, and underground piping to carry the water to detention ponds and/or the storm sewer system. The “green” alternative used planted bioswales throughout the parking lot, curb stops at some parking spaces to allow for surface drainage into bioswales and a water collection system to divert the roof water into a channeled weir as an amenity which leads to the on-site pond. The general contractor priced both alternatives while we held our breath………… the green alternative checked in right at 3% less than the conventional plan for the overall site improvements.

Johnston Memorial "green" site plan

You might say that a 3% cost savings is not significant, but the green plan has the added advantage of making the site more aesthetically beautiful while meeting the stormwater needs. The conventional plan priced ordinance-required landscape only while the “green” plan provided considerably more landscaping (5x the ordinance plan) to densely plant the bioswales for water quality purposes while reducing sod and irrigation. The additional benefits of this solution, beyond water quality and allowing for infiltration and recharge of the insitu soils, were providing wildlife habitat, reduction of life cycle costs through reduced maintenance and water cost for irrigation and a “free” water feature through the roof collection system diverted through a structured weir. Studies done by Texas A&M also show that views of landscape and natural systems also benefit the healing process, not to mention the mental health of the staff and visitors to the facility. An intangible that was also a factor was the speed with which the green alternative made it through the planning process and permitting.

At Johnston Memorial Hospital in Clayton, NC, the total site area was approximately 75 acres. For the” green” plan, over 39,100 sf of the parking lot was designed as bioswales giving an impervious to pervious ratio of 4.5:1 (176,000 sf: 39,100 sf). The bioswales were planted with almost entirely native plant material, which are well adapted for this situation. Plants like clethra, wax myrtle and itea formed a basis for the woody shrubs and native grasses and reeds like panicum, river oats and juncus added to the mix. Native perennials like aster, black-eyed susan and joe-pye weed add seasonal color without the replanting and maintenance cost of annuals.

We appreciated having a client go through this exercise of comparison, and we love being able to provide a client with a solution that saves them money and is more sustainable for the environment at the same time.

-Kim Hawkins


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Categories : Bioretention, Sustainable Site Strategies

Getting the Facts: Monitoring Green Infrastructure

8 01 2010

In Wednesday’s post, I mentioned the benefits of monitoring to help explain the reasons why green infrastructure facilities are being employed in their neighborhoods and specifically their effectiveness in improving water quality in our rivers and stream for which we all depend.

The City of Portland has done a great job at monitoring their green streets and other green infrastructure facilities. They provide this information on the Bureau of Environmental Services’ (BES) website. Their 2008 evaluation of their green street facilities have shown that for a 25-year storm event ( 25-yr, 6-hr) that peak flows were reduced by 80% or more. For CSO compliance events, their studies were shown to capture 60% or more of the storm volume.

It appears less has been published by the City on the pollutant removal capabilities for green streets. However, as mentioned in the article, studies conducted across the country have shown bioretention areas, the main stormwater management component of a green street, have been shown to be very effective. EPA’s fact sheet on bioretention shows the following removal rates:

  • Total Phosphorous: 70%-83%
  • Metals (Copper, Zinc, Lead): 93%-98%
  • Total Kjehldahl Nitrogen (TKN): 68%-80%
  • Total Suspended Solids: 90%
  • Organics: 90%
  • Bacteria: 90%

These number continue to be supported through researched conducted over the last decade. The concern that the accumulation of these pollutants, particularly metals will pose health risk have been unsubstantiated. A four-year study by Philip Jones (student) and Dr. Allan Davis (advisor) at the University of Maryland, showed the level of pollutants that accumulated within a bioretention cell on campus to exceed soil background levels but were far below EPA cleanup standards.

It is important to remember that currently, most conventional stormwater devices have no capacity to address pollutant removal. Portland is at the forefront in implementing green infrastructure practices and will be well positioned as Federal standards continue to be strengthened over the coming decade. More importantly, they are improving the water quality of their rivers for future citizens.

If fact, the EPA recently announced they are conducting stakeholder input in an effort to initiate a national rulemaking that would establish a comprehensive program to reduce stormwater discharges from new development and redevelopment and make other regulatory improvements to strengthen its stormwater program. At a minimum the EPA intends to propose a rule to control stormwater from newly developed and redeveloped sites, and to take final action no later than November 2012.

-Brian Phelps


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Categories : Bioretention, Green Street

EPA’s Green Infrastructure Statement of Intent

28 12 2009


Structured Rain Garden at
Tennessee Association of Realtors, Nashville, TN

In 2007, the Environmental Protection Agency (EPA) issued a Statement of Intent that recognized the viability of green infrastructure as a legitimate and effective tool that can be used to protect our water sources from non-point source pollutants. The statement was signed by the National Association of Clean Water Agencies, Natural Resources Defense Council, Low Impact Development Center, and the Association of State and Interstate Water Pollution Control Administrators. The objectives of the statement included the following (direct excerpt from Statement of Intent):

  • Affirm the belief by the signatory organizations in the value of green infrastructure as both a cost effective and an environmentally preferable approach to reduce stormwater and other excess flows entering combined or separate sewer systems in combination with, or in lieu of, centralized hard infrastructure solutions
  • Establish a framework for working together to advance an understanding of green infrastructure as a tool for reducing overflows from sewer systems and stormwater
  • Identify partnership opportunities between the signatory organizations
  • Develop strategies to promote the use of green infrastructure by cities and utilities as an effective and feasible means of reducing stormwater pollution and sewer overflows such as:

-Developing models for all components of green infrastructure and make them available nationwide.

-Exploring opportunities and incentives for the use of green infrastructure provisions in MS4 permits and CSO Long Term Control Plans (LTCPs), including as a component of injunctive relief provisions of enforcement actions

-Developing memoranda and guidance materials, including language for the NPDES permit writer’s manual, that would explain how regulatory and enforcement officials should evaluate and provide appropriate credit for the use of green infrastructure in meeting Clean Water Act requirements

-Recognizing the most effective and innovative uses of green infrastructure to meet Clean Water Act goals through EPA awards or recognition programs

-Providing technical assistance, training, and outreach to potential users of green infrastructure, including states, cities, counties, utilities, environmental and public health agencies, engineers, architects, landscape architects, planners and nongovernmental organizations

-Establishing a web-based green infrastructure resource center at EPA to assist communities in complying with requirements for combined sewer overflows and municipal stormwater permits and evaluating the multiple environmental benefits that green infrastructure can provide

-Developing tools to assist local green infrastructure programs with outreach, training, model development and application, planning and design, monitoring, and plan review

It has been almost three years since this statement was released. In that time, we have come a long way. There has been a tremendous increase in attention to green infrastructure within municipalitie’s overflow control plans and integration of best management practices into city stormwater manuals. We have gone from having to convince municipalities to employ green infrastructure practices, to being encouraged to use them by the same agencies. With Philadelphia proposing an all green infrastructure solution to the EPA for addressing the city’s overflow plan, it will be interesting to see how the EPA responds.

A recent New York Times’ article, “City’s ‘All Green’ Stormwater Plan Raises Eyebrows at EPA” underscored the unique approach the City of Philadelphia is taking. I thought Howard Neukrug summed it up well. He was quoted as saying:

“We recognized that if we manage stormwater where it lands, whether on the ground or on a roof, that in very many circumstances we can not only prevent that gallon of water from overflowing, but we may be able to find additional benefits for our customers…Things that impact the urban heat island effect, things that improve the aesthetic of a community.”

As we enter this new decade, we can be assured that green infrastructure will increasingly be a part of the solution.

-Brian Phelps


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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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Categories : Plans and studies, Sustainable Site Strategies, Uncategorized, Urban Planning & Design

EPA Releases Technical Guidance for Implementing EISA Section 438

9 12 2009

Just in case you missed it last week among all of the other pressing news stories, the EPA released a report outlining technical guidelines for implementing the stormwater runoff requirements for federal projects under Section 438 of the Energy and Independence and Security Act (EISA). In effort to afford designers maximum flexibility, the guidance provided is performance-based. The Section 438 of the EISA established the following requirements:

“Storm water runoff requirements for federal development projects. The sponsor of any development or redevelopment project involving a Federal facility with a footprint that exceeds 5,000 square feet shall use site planning, design, construction, and maintenance strategies for the property to maintain or restore, to the maximum extent technically feasible, the predevelopment hydrology of the property with regard to the temperature, rate, volume, and duration of flow.”

On October 5th, the White House issued a Presidential Executive Order addressing this requirement. The Executive Order titled “Federal Leadership in Environmental, Energy, and Economic Performance.” It required the EPA in coordination with other agencies to develop guidelines for implementing Section 438 of the EISA within 60 days. The current publication meets these guidelines.

The guidelines establish two options for meeting Section 438. The first option is to retain 100% of a rainfall event on site that is less than or equal to a 95th percentile. A 95th percentile rainfall event is an event with a volume over a 24-hr period that is equal to or less than the volume of 95% of all rain events for a period of record (i.e. 20 to 30 years). The table from the report provided below shows the size of the 95th percentile events for various cities across the Country. The events range between 0.7 to 1.8 inches of rainfall. These events commonly known as a “first flush” event were identified because they often contain the highest level of pollutants. Option 2 allows designers to conduct their own hydrological analysis and determine the site specific pre-development hydrological conditions. This options states that “temperature of runoff should not exceed the pre-development rates and the predevelopment hydrology should be replicated.”

For both of these options, the guidelines encourage the use of green infrastructure stategies. The guidelines recognize that “runoff event frequency, volume and rate can be diminished or eliminated through the use of green infrastructure (GI)/Low Impact Design (LID) designs and practices, which infiltrate, evapotranspire and capture and use stormwater”. The guidelines provide a number of studies that illustrate how green infrastructure can meet the established criteria. It is exciting to see the continued momentum green infrastructure is experiencing. If your considering working on federal projects, you will need to take a serious look at green infrastructure as an integral part of your site strategy.


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Kansas City Stormwater Overflow Control Plan

4 12 2009

Source: Kansas City, Missouri Overflow Control Plan Overview Document

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.

    -Brian Phelps


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    Categories : Bioretention, Green roof, Green Street, Pervious Pavement, Plans and studies, Sustainable Site Strategies, Water Harvesting

    New Downtown High-rise Includes Green Roof

    30 11 2009

    The Pinnacle at Symphony Place, a 29-story office building in downtown Nashville, opened this month. The building includes 520,000sf of Class A office space. It is home to law offices of Bass Berry and Simms and the headquarters of Pinnacle Financial Partners. The building designed by the award winning architectural firm Pickard Chilton with Nashville architects EOA Architects is anticipated to receive LEED-Silver certification from the United States Green Building Council (USGBC). With the inclusion of a 28,000sf rooftop garden, the building contributes significantly to Nashville’s ever growing green infrastructure

    The green roof, designed by our office, is located on the 7th floor above the parking garage and includes a series of spaces that can be enjoyed by the building’s tenants. The area is comprised of 9,400sf of pedestal pavers and 19,000sf of vegetated areas. One hundred percent (100%) of the pavers were selected to exceed the minimum solar reflectance standards established by the LEED rating system. The striping pattern continues the prominent vertical fins on the facade of the building into the rooftop garden area. The planting areas are a combination of extensive green roof (planting media depths ranging between 5-9”) and semi-intensive areas (planting media depths ranging between 18”-30”). The semi-intensive areas were planted to reflect a more traditional landscape around each of the gathering areas and provide areas for trees to shade and scale the spaces. In an effort to establish a more pedestrian scaled environment and additional interest a series of 12ft pyramidal trellis structures were incorporated in the extensive green roof areas.

    It is estimated that the green roof can retain nearly 67% of the annual rainfall falling directly on it. In addition, it reduces the peak flows, is significantly cooler than neighboring conventional roofs, reduces thermal heat gains in the water that enters the stormwater system, and provides a beautiful space to look upon and enjoy.

    We are honored to have been a part of such an exciting project and look forward to watching it grow. We have been pleasantly surprised by the significant growth the plant material has shown in a short time period. As it matures, we will keep you up to date on its progress.

    -Brian Phelps


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