Philly Recieves Approval for Green Infrastructure Plan

3 06 2011

Philadelphia’s Green City, Clean Waters Plan ,submitted to the EPA last September, has been signed by the PA Department of the Environmental Protection (PADEP) and the Philadelphia Water Department (PWD). According to PDW’s press release, it happened on June 1st. The approval of the plan is a big step in furthering green infrastructure’s legitimacy as a tool to address stormwater issues. The following are links to past post about the plan:

Triple Bottom Line of Green Infrastructure

Philadelphia Green Infrastructure Video

-Brian Phelps





Quantifying the Financial Value of the Soft Benefits of Green Roofs

6 05 2011

Steven Peck, Hon. ASLA, and Founder and President of Green Roofs for Healthy Cities was recently interviewed by The DIRT while in Washington D.C. for the Living Architecture Symposium, (“Despite the Economy, Green Roofs Bloom“). In the interview, Mr. Peck quoted a recent survey of the green roof industry  which reported that 8-9 million square feet of green roofs were built last year. This figure represented a 30% increase in market growth. Most of this expansion was focused in cities that have public policies in place that encourage and support green roof installation. The most intriguing statements in the article are those that helped quantify the economic impact of green roofs.

The post included some assertions that quantified the financial value of some of the soft benefits of green roofs. These included

“…average stormwater mitigation benefit is $4.26/sf” and  a view of a green roof improves property values of nearby buildings by 11%”

These figures are based on research by Smart Cities Research Services, Montreal.  “The Monetary Value of the Soft Benefits of Green Roofs” report prepared by Ray Tomalty, Ph.D. and Bartek Komorowski, MUP with the assistance of Dany Doiron, published last year. The report includes research on developing heuristic methods for quantifying seven soft benefits of green roofs: including: change in property values, marketing benefits, food production and food security, sound attenuation, stormwater retention, air quality, and green house gas (GHG) sequestration. The following is a summary of their findings:

I did not include the marketing figures in the table above, due the complexity of their findings.

Since there is little to no research specific to green roofs, the heuristic methods described in the report rely on other related research. Examples include:

Supply and demand play a critical role in determining one values and this is not any different for green infrastructure. For urban areas that may incorporate little to no green infrastructure (i.e. parks, green roofs, street trees) and are predominantly unsightly parking lots and roofs, projects that include green roofs should be more valuable and those properties surrounding it should benefit in some way as well. The report provides a great starting point for financially quantifying the soft benefits of green roofs. Over time, data specific to green roofs will eventually become available and we will be able to more accurately quantify their specific benefits.

-Brian Phelps





NYC’s Green Infrastructure Plan

18 11 2010

Last week, the Economist in an articled titled “Trees grow in Brooklyn” reported on U.S. cities implementing green infrastructure strategies to address the pollution of their waterways from storm water runoff. The article focused primarily on New York City and Philadelphia.

According to the article nearly 27 billion gallons of untreated water overflows into the New York harbor each year. NYC’s recently released green infrastructure plan seeks to address run-off from 10% of the impervious surfaces in the City with green infrastructure storm water strategies that range from rain barrels to pervious pavements to green roofs.

The plan estimates that on average the cost per gallon of Combined Sewer Overflow (CSO) avoided ranges between $1 to $2 per gallon. In addition, the City calculates that over a twenty-year period, it will receive between $139 million and $418 million in additional triple-bottom line benefits (i.e. energy savings, increase in property values, health) from the green infrastructure.

While NYC’s strategy is also employing grey infrastructure, they see the combination of the two costing less than a grey only approach. The cost of the green-grey strategy is approximately $5.3 billion of which $2.4 billion makes up the cost of the green infrastructure. This is $1.5 billion less than the grey only solution.

Chris Strickland, a deputy commissioner with the New York’s Department of Environmental Protection sums it up in the article saying that this (green infrastructure plan) is a way of achieving more than one thing with tax dollars.

Link to NYC Green Infrastructure Plan

-Brian Phelps





Philadelphia Green Infrastructure Video

7 09 2010

I recently came across this video covering Philadelphia’s Green Infrastructure Efforts. It was created by GreenTreks, an award-winning Philadelphia-based non profit communications organization dedicated to educating people about the interconnectedness of environmental, societal, economic, and individual health. For more information and links to other resources on Philadelphia’s triple bottom line green infrastructure strategy  see our past post  Triple Bottom Line of Green Infrastructure.

Brian Phelps





Metro Green Infrastructure Master Plan Now On-line

1 09 2010

Metropolitan Nashville-Davidson County’s Green Infrastructure Master Plan is now available on Metro Water Services’ website. The plan was prepared by amec, Hawkins Partners, Urban Blueprint, and the Low Impact Development Center. The plan includes the following:

  • 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





Ecological Importance of Southeastern Rivers

10 03 2010

Interpretive signs for an upcoming project near the Harpeth River in Williamson County will highlight the ecological significance of the waters of the southeastern United States. If you didn’t know, the rivers and streams of middle Tennessee are part of the most unique and diverse freshwater ecosystem in the entire world. This has to do with a couple things, namely the temperate climate combined with the fact that much of the area was unglaciated, or it as been more geologically stable than other parts of the U.S.

Just to give you an idea the area is home to more than 250 species of crayfish (70% of all the species in the entire U.S.), more than 300 species of mussels (over 1/3 of these live in Tennessee), and more than half the freshwater fish species in the U.S. Because of this great diversity, Tennessee has more freshwater fish that are at-risk than any other state. These species are at-risk largely due to pressures from development practices, which allow sediments and pollutants to wash into our rivers and streams. This and other topics concerning protection of critical watersheds can be found in, Rivers of Life or States of the Union: Ranking America’s Biodiversity, just some of the publications found on the NatureServe’s website.

Graphic from 'Rivers of Life', published by NatureServe

As mentioned in an earlier post, the implementation of ‘green street’ practices on Deaderick Street in downtown Nashville will divert approximately 1.2 million gallons of stormwater a year from the Cumberland River. This is water that would have otherwise run unabated into the river carrying all of the pollutants and sediments from the street. Understanding the significance of the region’s biodiversity is a good reminder of what we are trying to protect when implementing green infrastructure planning and strategies –and why this is especially important here in the Southeast and Middle Tennessee.

-Sara Putney





Updated Tree Carbon Calculator

18 01 2010

I know as landscape architects it seems like we are always talking about trees, but there are just too many good reasons not to, especially in urban scenarios. On our Deaderick “green street” project we made the focus of one of our environmental education signs on the importance of urban trees. The Center for Urban Forest Research, run by the US Forest Service provided a wealth of facts and resources for us to include on the Deaderick Street sign.

One of the Signs from Deaderick Street

Recently, the Forest Service has updated their Tree Carbon Calculator so that it works nationally instead of just for California. You can find the updated version in their Climate Change Resource Center. The calculator runs off an excel platform and allows you to input data for a single tree. Based on your region, tree species, distance for the building, and a number of other factors it will give a basic idea of how much annual energy, emissions and stored carbon you can expect. I used it to see the effects for a couple of trees I have outside my house. Even a small 6” tree has the potential to sequester over 65lbs of carbon dioxide from the atmosphere per year and that big 30” oak tree in my back yard, over 1000lbs per year, not to mention all the energy reductions too.

This is another useful tool to help prove the value trees. It is projected that over the next 50 years climate change will actually cause the southeast region to become warmer and drier, which would reduce the amount of forest growth. While the best option for managing this in the future is to keep forest as forest (per a publication from the US Forest Service titled ‘Forest and Carbon Storage‘), it can’t hurt by incorporating as much urban tree growth into new developments as possible, every little bit makes a difference.

-Sara Putney