December 1, 2011 Vol. 1, No. 9
The Houston LID Experience
Robert Adair, Steering Committee Chair, Houston Land/Water Sustainability Forum
Often thought of as an example of urban sprawl, Houston now is seen by many at the U.S. Environmental Protection Agency (EPA) as a model for moving rapidly toward sustainable development.
“[Houston] just implemented an amazing, consciousness-raising process that has at least hundreds of developers, civil engineers, architects, landscape architects … thinking differently about stormwater,” said Dov Weitman, chief of EPA’s Nonpoint Source Control Division. “And the way they did it seems to me to be replicable in cities across the country.”
Houston started its journey toward low-impact development (LID) from the same place that most communities do. Many within the engineering community thought sustainable development would never work in Houston because the city’s soil composition, topography, and rainfall patterns differ from typical LID sites. More to the point, LID’s decentralized, microscale controls, and extended time of concentration methodology meant embracing a 180-degree shift from the city’s current drainage model.
However, a visionary group — the Houston Land/Water Sustainability Forum (HLWSF) — took charge and promoted the cause. The group’s consensus was that LID could be adapted for Houston and there were overwhelming reasons to do so.
The HLWSF Steering Committee represents local organizations with both a vested interest in Houston’s development and the combined expertise to make the call on LID. For almost 2 years, the HLWSF offered educational programming aimed at local design, construction, and regulatory communities. This was not, however, enough to convince communities to try sustainable rather than standard designs and projects, especially during a recession. Engineers meeting with prospective clients were unlikely to propose innovative projects they had never done themselves.
Therefore, the HLWSF conceived the LID Design Competition to match developers with projects that had actual site data, and connected developers with owners interested in LID. Integrated design teams were required to submit runoff curves below predevelopment levels for 5-, 10-, and 100-year storms, and cost comparisons between the team’s LID design and a traditional design. Some of Houston’s most conservative engineering firms participated in the competition.
Without significant local stormwater quality regulatory drivers in place, LID in Houston would be implemented only if it performed well economically. In fact, that is exactly what happened. Results reached by the 22 competing teams consistently showed that LID is not only environmentally sustainable, but also more marketable, more valuable, and less expensive to construct.
In the year and a half since the competition, the number of LID-based projects in Houston has grown exponentially. There were hurdles along the way — working around existing codes presented obstacles to permitting, for example, and there were construction and maintenance questions. Yet, the development culture in Houston is changing, and much as the city has provided leadership in LEED Green Building, it is poised to lead the nation into the new stormwater and sustainable development paradigm.
Read more │ See an EPA webcast
Evaluating Stormwater Outreach: Is Anyone Listening?
2–3:30 p.m. EST
No-charge WEF webcast
WEF/CWEA Stormwater Symposium 2012
July 19–20, 2012
Member Association Events
Michigan Water Environment Association
2011 Watershed Seminar
NPDES Phase II stormwater issues and watershed planning implementation
Federal Water Quality Association
Exploring the Value of Clean Water
U.S. Geological Survey
Nutrient Decision Support System
Water Environment Research Foundation
WERF Online Research Forum
11 a.m.–5 p.m. EST
2011 Great Lakes Restoration Initiative Quality Technical Conference
APEGBC: Stormwater Modeling
Kelowna, British Columbia, Canada
CHI International Conference on Stormwater and Urban Water Systems Modeling
Feb. 22–23, 2012
Toronto, Ontario, Canada
EPA Revises Numeric Limits for Runoff From Construction Sites
On Nov. 16, the U.S. Environmental Protection Agency (EPA) sent the Office of Management and Budget revised construction and development effluent limitation guidelines (ELG). The agency withdrew numeric turbidity limits proposed in 2009. These new guidelines are based on new treatment performance data and will set the first numeric limits for stormwater runoff.
The numeric limits will replace the technology-based ELG limits currently used in EPA’s construction general permit. The agency extended the expiration date for its current general permit to Feb. 15, 2012, to provide time to revise the ELG and offer a public comment period. In July, WEF gathered comments expressing concern that a nationally applied numeric standard would be problematic because of differences in local conditions, such as terrain, soil, vegetation, precipitation, and other factors.
Idaho Supreme Court Rules Stormwater Fee Unconstitutional
In early November, the Idaho Supreme Court ruled the city of Lewiston’s stormwater fee unconstitutional because it qualified as a hidden tax, as it was not previously authorized by the Idaho legislature. The fee — levied in 2008 — was based on impervious surface area. However in 2009, a local state college, port, school district, irrigation district, and Nez Perce County filed a lawsuit against Lewiston. In Idaho, local governments cannot tax one another, so by classifying the stormwater fee as a tax, the plaintiffs would not have to pay.
The ruling was made in part because the Idaho Supreme Court classified the fee as revenue-generating and because the city charged property owners regardless of whether they used the stormwater system.
EPA Study Lends Support to National Ban on Coal-tar Sealants
According to a new U.S. Environmental Protection Agency (EPA) study, a ban on coal-tar sealants may be the most cost-effective means of controlling polycyclic aromatic hydrocarbon (PAH) pollution in runoff. EPA showed that concentrations of PAHs in runoff from coal-tar sealants are 100 to 1,000 times greater than other sealants tested, and most PAHs are released within the first 24 hours of application. The study, Assessment of Water Quality of Runoff from Sealed Asphalt Surfaces, compliments U.S. Geological Survey studies showing that, on average, coal-tar sealants accounted for half of PAH inputs in 40 urban lakes studied. Rep. Lloyd Doggett (D-Texas) requested the EPA study and will continue working on legislation to phase out coal-tar sealants nationally, following the example of several local governments.
Environmental and Industry Groups Oppose D.C.’s MS4 Permit
The The U.S. Environmental Protection Agency (EPA) faces opposition from both environmental groups and industry over the District of Columbia's landmark municipal separate storm sewer system (MS4) permit. The permit is considered a model for future MS4 permits across the region and the country. It requires infiltration-based stormwater management techniques, such as green roofs and bioretention facilities, to retain a minimum of 1.2 in. (30 mm) of stormwater runoff onsite, representing 90% of the rainfall events that occur in the Washington, D.C., area in a typical year.
However, a petition filed by environmental groups on Nov. 4 argues that EPA should control the permit compliance schedule, and that the permit does not mandate water quality compliance as long as facilities comply with the retention standard. In contrast, industry groups petition that some of the permit's numeric goals are not achievable, and that there is a lack of clear distinction between utilities' responsibilities and those of the District of Columbia.
Pesticide Applications Now Subject to Clean Water Act Permits
Pesticide applications near U.S. waters are subject to Clean Water Act permitting by the U.S. Environmental Protection Agency (EPA). This change went into effect Oct. 31. The final pesticide general permit applies in locations where EPA has permitting authority. Authorized states have been developing their own draft permits. Applicators will have until Jan. 12, 2012, to meet the requirements. More information
NRDC Releases Green Infrastructure Report
The Natural Resource Defense Council (New York) recently released a report, Rooftops to Rivers II: Green Strategies for Controlling Stormwater and Combined Sewer Overflows. The report discusses the benefits and economics of green infrastructure, including funding mechanisms; provides policy recommendations at the national, state, and local levels; and includes case studies from 14 cities.
Archived Videos Now Available
The U.S. Environmental Protection Agency (EPA) webcast “Conducting Effective Stormwater Outreach” is now archived and available for free. The webcast features EPA's Nonpoint Source Outreach Toolbox and ThinkBlueMaine's rubber duck campaign.
The U.S. Geological Survey (USGS) also has posted video footage of a recent congressional briefing on the SPARROW model. At the briefing, USGS discussed a new online decision support system for identifying nutrient sources to downstream waters. The tool gives decision-makers a way to evaluate nutrient reduction scenarios based on a variety of sources from agriculture to wastewater treatment plants.
EPA To Study Economic Importance of Clean Water
The U.S. Environmental Protection Agency’s (EPA) Office of Water is conducting a study on the importance of clean water to the U.S. economy. According to a notice in a Nov. 14 Federal Register, EPA will hold a Dec. 5 teleconference to provide opportunity for public comment. The agency is looking for input on how the availability of clean water affects economic development patterns and creates advantages for various economic sectors, as well as what data are available or needed to support strategic choices.
Los Angeles Gateway Authority Screens Trash From Los Angeles River
Last month the Los Angeles Gateway Authority, a coalition of 16 cities, completed a $10 million project to prevent 381,018 kg of trash from entering the Los Angeles River. The project involved retrofitting 12,000 publicly held storm drains with screens that capture trash. The authority used connector pipe screens, and areas with high trash loads also received automatic retractable screens. More information.
Roof Type Influences Rainwater Capture
According to a recent study by researchers at the Autonomous University of Barcelona (Spain), sloping roofs made of plastic or metal can capture higher quality stormwater and up to 50% more rain than flat, rough roofs. This study by Ramon Farreny and other researchers was a follow up to research on the cost efficiency of rainwater-harvesting strategies and an analysis of harvesting infrastructure in urban environments. Read more
New York Completes Green Infrastructure Pilot Project
New York City recently completed the first pilot project of the NYC Green Infrastructure Plan. This project is part of a larger $2.4 billion plan to reduce combined sewer overflows, $187 million of which will be spent on green infrastructure projects. The first project is located within the Bronx River watershed at the Central Housing Authority's Bronx River Houses. It includes a blue roof, rain gardens, stormwater chambers, and a perforated pipe system designed to capture 121 m3 during just one rain event. The city’s Department of Environmental Protection (DEP) recently unveiled another pilot project on Gowanus Canal, which is designated as a federal Superfund site. At the launch, DEP displayed four vegetated tree pits with curb cuts designed to capture 72 m3 stormwater. DEP plans to install 40 more pits throughout the city. Read more
University of Florida Students Place First With Stormwater Design
University of Florida (Gainesville) placed first in the environmental design category of the Water Environment Federation (Alexandria, Va.) Student Design competition with the project “Stormwater Cycling Design Options in an Urban Industrial Watershed.” The group Semper Aquam compared the effectiveness and cost of several options for treating stormwater at an 80-ha (200-ac) industrial facility challenged by particulate matter and metal discharges. Team members selected a process for capturing, treating, and using stormwater for cooling at the facility. Read more
Check It Out!
Culverts are designed to funnel stormwater under roadways, but these structures are carrying more than just water. A study from the University of Maryland’s Center for Environmental Science uncovered the diversity of species that use culverts to travel beneath highways. They found that close to 60 species use the culverts, from grizzly bears and moose in Canada to panthers and alligators in Florida. The study also looked at the type of culverts animals prefer. With 6.2 million km of paved roads in the United States, animal habitat is fragmented. However, culverts could be used to improve road safety for animals and humans.