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• Integrating Stormwater

Miller has developed two zero-energy homes featuring rainwater-harvesting systems in the arid desert of Tucson, AZ. And, while water conservation is a selling point for homebuyers, most don’t understand anything about stormwater, Miller says.

“First you get them to understand solar energy and energy conservation and the effects of things on the planet, and then you get them to understand the connection between water and energy and energy and water,” says Miller.

“Then you go to the last thing: water runs off and becomes stormwater. Most people don’t care about stormwater unless they get flooded. Storms are the best way to get people to understand stormwater.”

Miller represents a host of developers incorporating an increasing number of sustainable stormwater designs into their developments. Some are in response to government requirements to do so for publicly funded buildings. Others seek to accommodate clients requesting more “green” features in their homes.

And many companies constructing new buildings are responding to an increase in standards focusing on a slate of green products and designs, including stormwater.

Among the major considerations in sustainable stormwater design: cost, space, location, maintenance, and regulations.

Leadership in Energy and Environmental Design (LEED) for Homes and the National Association of Home Builders’ (NAHB) respective development standards will mean that builders who wish to attain certain certification levels must consider how they will design the landscape for stormwater runoff and treatment. Retaining stormwater onsite for irrigation use, for example, helps save domestic water use and costs.

The EPA reports that an American family of four uses up to 400 gallons of water per day, with 30% of that for outdoor uses. More than half of that is used for landscape irrigation.

Ann Archino Howe, a civil engineer whose specialties include sustainable site design, works with municipalities in finding solutions for stormwater concerns.

“Stormwater is the major site issue we are confronted with all over the country,” says Howe, of the Sustainable Design Studio in Portland, ME.

“At this point, we’ve built on all of the easy sites,” she says. “Until recently, we have seen stormwater as a waste product of development instead of as a resource. So we are looking much more carefully at the long-term effects of developing a particular site in a particular watershed—not just the site effects, but the watershed-wide effects on streams, lakes, erosion issues, and sedimentation.”

Larry Coffman, president of Stormwater Services in Chesapeake Beach, MD, points out that with the advent of Phase II of the National Pollutant Discharge Elimination System (NPDES) most local jurisdictions are concerned about compliance.

“However, it really depends on where you are around the country in terms of the importance of stormwater management,” he says.

Compared to other parts of the country, storms in Maine tend to last longer, so Howe will design based on a 24-hour design storm.

“I know in some parts of the country, they base their designs on 30 minutes for a lot of storms,” she adds. “That’s one of the difficulties in talking about techniques that work in one part of the country, but not in another part. But there are certain basic things you can always choose, although everybody needs to be thinking in terms of what kind of storms they have.”

Coffman points out that a major concern in US coastal regions is protecting the biological integrity of the receiving waters and the fisheries. “For them, urban stormwater runoff and retrofit is a big issue, whether they’re dealing with the coastal bays or need to reduce the influx of pollutants to protect shellfish and other fisheries,” he says.

“In other parts of the country, the concern is with water supply—maintaining the volume, integrity, and quality of the water being used. In some areas, they are interested in stormwater management for control of combined sewer overflows. There is a wide range of important issues that stormwater touches upon. One of the things we are seeing in the industry is a broadening of the understanding of the importance of stormwater management.”

Conditions under which a developer would choose alternative methods of sustainable development depend on the developer’s goals for the receiving waters, Coffman says.

“Your stormwater management technologies help achieve those goals, whether it’s restoration of impaired water, protection of a reservoir, or protection and restoration of fisheries,” he says.

However, he points out, “Stormwater technology is not designed to restore the integrity of receiving waters. Conventional technology is really designed to meet the minimum standards set by federal and state governments. Generally, those are insufficient and inadequate to restore receiving waters. Reducing the impacts of urbanization probably isn’t good enough to get us where we want to go.”

“Low Impact” Versus “Sustainable”
Howe differentiates the term low-impact development (LID) as a term used by the EPA and the stormwater treatment industry and focusing primarily on stormwater issues, whereas sustainable site design is a broader term encompassing other green measures as well.

“There has to be a shift in our thinking if we are doing low-impact development or sustainable design,” says Howe. “With low-impact development, the approach to design is that, instead of considering the whole site as kind of a monolith we look at the site in its existing condition and at small areas.

“For example, you would never design a bioretention bed to treat the runoff from a 50-acre parcel; an acre or two at the most is really what we’re talking about for most of these BMPs [best management practices]. That means you usually have more BMPs on a site, but each one can be smaller and fit into the landscape better.”

For years, Coffman worked for Prince George’s County, MD, developing and promoting LID techniques. He says he did so with a thought of finding simple and inexpensive techniques that developers could use.

“It’s basically optimizing the use of the landscape to the best extent possible, and not just minimizing the impacts of stormwater runoff, but replicating the water balance,” he says. “It boils down to being more aware of how we can work with the landscape to make it work for us instead of against us.”

In pursuing LID, Coffman always considered the continued degradation of receiving waters in the Chesapeake Bay area despite the use of conventional approaches.

“If you want sustainability, you have to have technology that in some ways mimics natural ecological processes and functions that serve the receiving waters and aquatic resources in those waters,” Coffman points out.

Sustainability is becoming a more common trend in stormwater design, Howe notes. “I’ve been using LID for years, but a major thing happened a few years ago in Maine when our state’s stormwater law was changed to focus on impacts to urban-impaired streams and lakes most at risk for new development,” she says.

“The Maine Department of Environmental Protection is pushing low-impact and sustainable development by requiring quality treatment of the stormwater of any project that disturbs more than an acre, which is quite strict—it may be one of the stricter laws in the country,” says Howe, who helped to rewrite the law.

“What we are trying to do is mimic the hydrology of existing conditions in the developed conditions through the use of such things as bioretention beds, wet ponds with gravel filters, underground filtration beds, and grass swales,” she says.

One technique Howe favors is preserving existing vegetation, particularly trees. “One 50-year-old oak will take up a huge amount of stormwater in the leaves and roots,” she says.

She points out that one of the major aspects of all sustainable stormwater techniques is that “there has to be a total mind shift in how the designer thinks of the site as it fits in the larger surroundings, whether that’s the watershed or an open area. The typical practice probably most all of us did for years was building a pond—a wet pond, a dry pond, a detention area—and then piping or directing all of the stormwater runoff from the site to that pond.”

Simple approaches to sustainability include reducing impervious areas, Howe says. In one office-building project on which she is working, Howe reduced stormwater runoff by negotiating with town officials and regulators to reduce the width of the entrance, using grass for the shoulders instead of gravel or pavement, reducing the aisle width in the parking lot, and reducing the parking space length.

“A foot here, a foot there—all of these things reduce the overall impervious area on the site,” she notes.

Howe uses other approaches as well.

“A bioretention bed is depressed from the existing or finished grade no more than 6 inches, and then there is at least 18 inches of a special soil mix designed to provide the nutrients for plant growth and treat stormwater runoff—whether from a roof, parking lot, or from a road,” says Howe. “Pollutants can be hydrocarbons, heavy metals, sediments, phosphorus, and other materials.”

In some parts of the country, bioretention beds infiltrate into the ground, says Howe. In Maine and elsewhere, they infiltrate even in native soils that are clays, she says, adding that Maine has soft marine clays.

“There are places where it can’t infiltrate, so a standard cross-section for a bioretention bed often includes another layer below the filtration soil that is an underdrain. Then you outlet at some point so it does not cause erosion problems,” she explains.

The bioretention beds can be planted with grass that can withstand an inundation of stormwater and then dry out, or they can be incorporated as part of the landscape design, Howe says. She works closely with landscape architects on a project design that places bioretention beds among native shrubs, ornamentals, and ornamental grasses.

Another stormwater BMP that Howe favors is an underdrained filtration bed.

“The difference between that and bioretention is that you can have up to 18 inches of storage, but otherwise you have 18 inches below that of special filtration soil that takes out pollutants and takes up a lot of stormwater so it doesn’t actually get to the underdrain layer below that,” she says.

“Usually you detain about the 1-inch storm, and then you have an overflow so that runoff from larger storms will then bypass and leave the area.”

A wet pond is another tool used by Howe.

“I designed a wet pond for a project in Augusta that became a design feature with a fountain, but the key element is that it treats stormwater,” says Howe. “The first one and a half inches of stormwater is treated through a gravel filter along the side. It’s not intrusive; it fits right into the landscape.”

Howe says she also tries to do more with pervious pavement, although she notes that in some areas it has been slow to be accepted. “One of the key things you need to use pervious asphalt and make it cost-effective is that the state’s department of transportation has to adopt what’s called an open-graded asphalt mix,” she says. “It’s a standard mix; otherwise, if you’re trying to incorporate pervious asphalt, it’s a special mix and is extremely expensive.”

Some people are designing walkways with pervious concrete, however, says Howe. “With all of these methods, you are treating that stormwater and recharging the groundwater,” she says.

Because Maine has many rural sites, Howe also uses undisturbed forested areas as a path through which stormwater can be discharged, with the sediments and other pollutants adsorbed by the plant material.

“[Runoff] goes through a stone berm that disperses the water so it doesn’t enter the wooded area in a concentrated form, and then—depending on the soil type—you have an undisturbed forested area you can devote to a buffer. That’s a low-impact design that wouldn’t work in an urban area.”

While green roofs are an area in which Howe is interested, there are few places in Maine with enough population to create heat island effects, a major driver for using vegetative roofs.

However, Howe does work with mechanical and building engineers to create systems to direct roof runoff to an underground tank, with an overflow filtration bed, for treatment and recycled use, such as toilet flushing.

Bob Jones, vice president and secretary of the National Association of Home Builders (NAHB) and president-elect for 2010, says builders throughout the country are employing numerous sustainable building practices to enhance collection of stormwater runoff and treatment.

Collecting Runoff
Landscape design that focuses on native plants that take up water is not only a beneficial use of surface water, but also eliminates the need for piping and “may also eliminate some detention areas in new developments that collect water and in some instances become eyesores,” says Jones.

Another example: rainwater collection and distribution systems for non-potable water needs.

“What we’re really talking about here are cisterns, which are really no more than tanks, but this kind of rainwater collection can be used for irrigation and flushing of toilets,” says Jones. “What you’ve got to figure is how you get the distribution. You would use pipe of one form or another to get into the house and some kind of a pump.”

Anything to conserve stormwater for onsite use is a plus in the arid Southwest, Miller points out.

In constructing on a tract of land in Arizona, Miller says his company first considers the land planning, utilizing stormwater to minimize or eliminate the need for domestic water.

“You do the land grading so you can retain the water on each lot as long as it is safe,” he says. “Then the whole development has good drainage. Because of our erratic rainfall—we’ll have no rain for six months and then the sky will drop out—we have to grade our development so we have retention/detention areas in our master planning.”

The water is retained onsite as long as possible, says Miller.

“There’s a large area that has to fill up to a certain point before it can run into the storm sewer and put a burden on the municipal system,” he says.

Stormwater conservation and domestic water-use go hand in hand in Miller’s development, Armory Park del Sol. A 2006 water use study indicates that when compared to Tucson’s water use of 247 gallons per house per day (GPHD) in homes constructed in 2000 or after, houses in Armory Park del Sol use 119 GPHD. The study shows that over a decades-long lifespan of a home, Armory Park del Sol residents’ water savings will exceed 1.4 million gallons for each home.

Miller, who uses rainwater-harvesting systems, acknowledges that they are not always the best-looking feature on a home lot.

“One of the problems with them is they’re ugly, just like the first solar units were,” says Miller. “If you are going to work with them, you’ve got to think about the aesthetics.”

To that end, Miller has employed sculptures as a way of making rainwater harvesting look attractive.

“Arizona especially likes copper, so we’ve got these little copper cups where the water runs out of the drain pipe and forms a little waterfall down the cups,” he says. “In a deluge, it spills over, but in a normal small rain, we fill up our tanks.”

Water from the tanks is used to irrigate the plants on a home’s patio. The gravity-powered tanks are aboveground. Appearance also is a consideration in tank design, with homeowners given the opportunity to choose the colors they want for the tanks.

“They’re a composite material that can blend into your patio décor, and they have screens on them so they don’t fill up with debris,” says Miller.

At the bottom of the tank is a drain and a hose. All of a home’s tanks are looped together to avoid the sight of “ugly pipes running all over,” notes Miller.

“Water seeks its own level, so we have a larger tank that’s not as attractive back behind the corner hidden by a small wrought-iron trellis, and it’s on the same underground loop,” says Miller.

A hose for landscape irrigation delivers the harvested rainwater. During arid times when there is no rainwater to harvest, a timed pump operates a drip irrigation system.

Miller’s company also educates homeowners to dig deeper tree wells so that when it rains, the water soaks in around the plants and stays there for as long as it’s safe.

“A lot of people create a tree well by digging down and putting a ring around it, which is raised, and then the rainwater can’t run into it from the rest of the yard,” he says. “Recess it rather than raise it.”

In the arid Southwest, “obviously we don’t have a stormwater problem most of the time, but then you get complacent. When we get a ‘gully washer,’ if we get an inch of rain, it hits that dry, baked earth and just runs,” says Miller.

And it floods.

“All of our new developments have retention and detention ponds. The idea is to try to keep it where it lands, so it doesn’t run over into the storm drain. Most of the time, we soak it in on the property, but if we have an extreme rain, it’s got to go somewhere or it will flood houses. It takes a lot of hydrological engineering calculations and good guesses,” says Miller.

It’s Miller’s goal that his development can be a source of education for other developers and builders.

“What we’re doing at Armory Park not only impacts water conservation, but the stormwater system won’t have to be remodeled and enlarged,” Miller says.

“It’s time for developers, builders, and homeowners to be proactive rather than reactive.”

Combining LID Features
Meanwhile, in the Midwest, Matt Belcher, a green builder in St. Louis, MO, is constructing a 170-acre development with about 280 units: a mix of townhouses, cottage homes, and detached single-family homes that will feature a number of green stormwater measures.

The community, Rock Hill Trails, is part of a larger area of acreage owned by a family that has operated the farm on it since pre-Civil War times. While they knew the area was ripe for development, the family is acting as its own development company in an effort to ensure the development stays true to their LID philosophy.

“They wanted to develop it using those techniques and also to build all of the homes green,” says Belcher. “They contacted me, and I jumped all over it because this is a phenomenal project.”

Among the many planned stormwater features:

• No storm sewers, but only piping to transfer water from one bioretention area to another
• Various curb structures to control water, such as V curbs or ribbon curbs
• Constructed wetlands in addition to bioretention areas. Roadside infiltration gardens, rain gardens, and other measures to control hardscape runoff will be used to slow down stormwater and channel it into bioretention areas. Some parking areas will feature depressed parking islands that capture and facilitate stormwater control.
• The construction of an underground cistern-type facility at the community center to capture water for its irrigation needs

The use of native plants also is playing a major role in the development’s stormwater control.

Belcher is working with Applied Ecological Services, which is helping to specify the types of native plants being used.

“We’re putting in the homeowners’ covenants, a recommended way the lot should be planted, and a big list of available planting materials they can use,” says Belcher. “We’re going to promote native plantings, because those are more drought-tolerant, hardier plants and negate the need for any type of additional irrigation.”

Additionally, Belcher’s company is including an allowance for the use of rain barrels, he adds.

Another product Belcher will be implementing is moisture meters to ensure wet ground is not being irrigated.

During the grading period, filter socks will be among the approaches used for stormwater control.

The development will be built in four phases. In the first phase, nearly every home site backs up to open space, says Belcher. “There’s either existing vegetation they back up to, or if it’s in an area where there was crop land, we’re putting in wetlands or bioretention areas or we’re going to establish prairie in the open spaces,” he says.

The company is moving away from the use of large detention basins and using more constructed wetlands that are also bioretention facilities. “They slow the water, clean it, and let the water pass through a functional habitat,” he notes. “The water is then treated both aerobically and anaerobically to maximize water quality.”

All of the stormwater is being engineered for handling through this system, Belcher adds.

“What’s going to happen is that no more water will leave this site than currently does, and any water that does leave it will actually be cleaner when it leaves the site because of the natural filtration,” he says.

Potential homeowners have expressed excitement over the development.

“You think it is going to have to be a big educational process, but it seems like a lot of people already have a basic idea and know enough about it that they want to learn more,” says Belcher. “We’ve received nothing but positive remarks from people interested in how things are going and when they can get out to see it, which is obviously a good thing.”

Working With the Regulations
Howe says she’s taken an interest in trying to figure out a way to work with regulators so they understand the consequences—in terms of sustainable design—of some of the regulations that are focused “on the convenience of the snow plow.”

“This is a northern US issue; I’ve talked with people from Minnesota who have the same problem,” she says. “The two issues that always come up are if you reduce the size or width of roads, it affects the speed of plowing and the safety for fire trucks.”

Yet, there are examples of how to address those challenges besides making everything bigger and wider, Howe contends.

“To me, that’s a part of sustainable design also—figuring out ways to reduce the overall imperviousness,” she says. “I try to work with architects to reduce the size of the footprint of a building on a site.

“Another piece of sustainable site design to me is reusing existing sites rather than trying to build on a green or undeveloped site,” says Howe.

After spending many years in the public sector, Coffman now works in the private sector as a consultant with Filterra, which sells a proprietary bioretention filtration device.

When he speaks to others in the industry, Coffman highlights what he sees as a need for the public and private sectors to partner in research and development and advanced technologies.

“One of the things Congress envisioned was that through the NPDES and total maximum daily load [TMDL] programs, new standards would be set higher and drive technology,” says Coffman. “Because everybody is required to do stormwater management, if local governments would set standards that would help to drive technology, the private sector is more than willing to put in the resources to do research and development to advance technology.

“I hope local governments see the private sector as a partner in this rather than this combative relationship where governments feel they have to regulate instead of encourage the private sector to come up with better designs.”

Developers will push sustainable technologies if the local regulations encourage innovation, creativity, and sustainability, Coffman says.

“I think the regulations now are working against improving technology and pushing sustainable-type development,” he adds.

Belcher credits local authorities in his area for setting a positive example of government and industry working together in his development project.

“The city of Wood River [Illinois] annexed this property, and they’ve been phenomenal to work with,” he says. “They’re big proponents of this. The biggest aid to gaining political acceptance is that they had an open mind and were willing to let us show them how it works.

“The civil engineer we used has to show his calculations, and Applied Ecological Services’ stormwater and soil scientists had to do the same thing,” he notes.

Applied Ecological Services had already developed Prairie Crossing in Grayslake, IL, with green features some 20 years ago.

“The proof is in the pudding,” says Belcher. “Luckily, our site is very accommodating for this, so that definitely helps. It’s been a good team to work with.”

Ironically, while some government entities and regulations appear to be putting the brakes on innovative sustainable development techniques, more municipalities and states are starting to drive the trend toward it, Howe says. That’s due in part to such initiatives being promoted by the US Green Building Council’s LEED rating system and the NAHB.

“That pushes everybody to think about building differently,” says Howe. “I am very impressed with the US Green Building Council. I am a founding member of the Maine chapter and am still on its board.”

But Howe believes that the LEED credits affiliated with a sustainable site are not raising the bar high enough. She knows there are others within the Green Building Council who share that opinion and will continue to work on those factors.

With NPDES’ regulations requiring post-construction stormwater management techniques, and as the LEED and NAHB green building standards are being rolled out, “you are seeing a lot of local governments take a leadership role in pioneering and experimenting with new techniques and technology,” says Coffman.

“You are using different techniques within a subdivision, dealing with conservation techniques, and minimizing impacts and use of a wide array of integrated practices and pollution prevention. It’s important for contractors, inspectors, and local governments to advocate the ability to ensure proper construction. Because we’re really getting into some comprehensive, complicated, and intricate designs that require knowledge, education, and experience by everybody involved in the process, from the design to the review to the construction to the inspection.”

Such technologies have better selling potential, notes Coffman, who travels throughout the country meeting developers who’ve adopted a “green” corporate philosophy.

“Many developers now really want to do this. They’re finding it profitable,” he says. “Most developers are members of their local community, so they’re there not just to build buildings, but to build communities, to participate in the community, and to protect the receiving waters.”

Sustainable development conferences are well attended by developers, Coffman adds. Those developing property can also find a wealth of information on LID and conservation design through the Internet, as well as through such organizations as the Low Impact Development Center, the Natural Resources Defense Council, and the NAHB, which offers an LID design manual that provides a comprehensive overview and case studies on how to build using LID and sustainable techniques, says Coffman.

Coffman points out that there are a number of areas throughout the country that have a more advanced approach to LID, such as the Puget Sound area in the Northwest. The Puget Sound Partnership Web page has extensive information on LID.

Portland, OR, and the Chesapeake Bay region in Virginia and Maryland also promote innovative sustainable designs and development, Coffman says.

“There are some hot spots around the country, particularly where they have important fisheries and water bodies they want to protect and are using the best techniques that they can.”

Retrofitting
Retrofit projects present their own challenges in terms of sustainable development. Howe has been a consultant for an environmental company that does a great deal of retrofit work for existing sites that have to meet NPDES Phase II stormwater requirements. The sites often have no stormwater controls.

“There’s no set formula for doing that,” Howe says of retrofits. “They have to incorporate berms that contain potentially polluted runoffs on the site so that it can go into a tank and be treated elsewhere.

“Sometimes it’s a matter of having the room to have some kind of a settling pond on the site. There are a lot of different solutions, but it’s harder to do them because most of these sites are in use.”

One “previously used” site is now under redevelopment by PN Hoffman, a developer of upscale condominiums and mixed-used properties in the Washington, DC, area. The company was the first developer in the District of Columbia to achieve LEED certification for a multifamily residential building, the Alta.

Among the green measures utilized in the Alta’s development is a green roof, chosen for improved air quality, a reduction in heat island effect, and control over the amount of water released to stormwater system.

The company presently is involved with Forest City Washington in the redevelopment of 42 acres of a former US Naval Yard annex along the Anacostia River, less than a mile from the US Capitol Building.

The site—called the Southeast Federal Center or “The Yards”—was originally operated by the US Navy and taken over by the US General Services Administration (GSA) more than 20 years ago. The GSA had removed several of the structures and retained the historic ones.

The area was an active manufacturing yard for the Navy, a hodgepodge of buildings quickly erected for wartime armament production. Much of the surface is impervious.

As such, there had not been a well-organized stormwater management runoff system. Rather, stormwater has flowed through surface catch basins and is directly discharged to the Anacostia River. The redevelopment project is adjacent to the river’s bulkhead.

PN Hoffman plans to use low-impact development designs and quantity-mitigation devices to minimize stormwater runoff into the municipal system, says Al Hedin, the company’s senior vice president of development.

“We’re essentially trying to replicate the capture of as much rainwater as we can through the use of green roofs and also through any of the streets and paved areas,” says Hedin. “We’re trying to utilize some of the stormwater management techniques that would help to at least separate and remove debris and also to purify some of the water itself prior to discharge.”

The LID aspects of the project will focus on overall design of streets, sidewalks, pedestrian areas, tree boxes, and lay-by areas for traffic. The area will include pedestrian seating and green buffers between bike lanes, traditional sidewalks, pedestrian walkways, and vehicular traffic.

The company also plans to collect rainwater in temporary basins.

Comparing Costs
Generally speaking, LID costs are typically lower than that of conventional approaches, with some exceptions, says Coffman.

“There are a lot of no-cost low-impact development techniques—how you lay out the site, the soils you save, the type of grading you do or don’t do,” he says. “These techniques really don’t require any kind of additional cost; it’s just thinking a little bit more about how you lay out your site in a way that is more sensitive to the landscape, the geology, and the water balance within a watershed.”

Other more engineered techniques can be more costly than conventional approaches, he adds.

“It depends on the site designer and the developer coming up with a strategy that optimizes the treatment and minimizes the cost,” Coffman says.

Location also is a consideration, he says. While green roofs can be costly, “if you are doing a new development in the middle of the downtown area, a green roof might be just as cost-effective as an underground vault system that would be extremely expensive underneath the building or in the street where you’ve got utilities located.”

Green roof technology has been in Europe for more than 50 years and is cost-competitive with other techniques, says Coffman. “Many developers in urban areas use green roofs just because it is the most cost-effective technique available.”

PN Hoffman’s Hedin says his company’s experience has shown that green roofs add a nominal cost to a project. “As long as they’re incorporated into the design early and are well thought-through, there is very little impact,” he says.

Howe also points out that sustainable stormwater designs can be more cost-effective than traditional approaches. “Until recently, the major BMPs for dealing with stormwater runoff were pipes, basins, and ponds, both detention and retention. Once built, this infrastructure was seldom maintained unless there was a problem. Many developers and owners still believe that it is easier to dig a hole in the ground for a pond than it is to mess around with all of these smaller BMPs located all over the site. You can buy plenty of plants, though, for bioretention or filtration beds before you’re spending the same amount of money that you will for a full underground system.”

Michigan green builder Arn McIntyre points out that green building associations are growing in membership on an ongoing basis, with an increasing number of homes being certified. More builders are taking training.

“You can look at that a couple of ways: there are builders out there who truly are the core of the organization, are environmentally conscious, and looking at sustainability,” he says. “Then there are builders who see the market need and see they have to get involved or they are going to be left behind. The general feeling of the builders who have been doing this—and even of the ones who have just started doing it but are very astute—is that in five to 10 years, green building will be the norm.”

Sustainable site design is vitally important as more building creates more impervious surfaces, Howe says, pointing to an increase in flooding events.

“There are still many wetlands, but in some cases, there’s no place for the stormwater to go,” she says. “We are destroying the reasons that people want to be—in this case—in Maine. I think people all over the country are beginning to think about that.”

Belcher says his company’s measures have an environmental benefit with respect to population growth.

“We’ve hit 300 million people in the United States last year, and they all need a place to live,” he says. “It’s good that our industry is looking at how we manage the resources it takes to provide that shelter.”