When developer Jim Paul first saw the large piece of farmland along Manhattan-Monee Road, in a rural part of Will County, he studied the landscape carefully. He might have mass-graded the site, flattened it and plunked down houses in orderly rows, following the typical order of suburban development. Instead he asked, how could this land be returned to a natural form?
To help, he brought in Bob Jankowski, of the U.S. Department of Agriculture’s conservation service. Jankowski’s trained eye discerned the original features of nature in the vestiges of woods and wetlands and the general shape of the land. A small pond stood near a weed-covered swale, which led back towards a running stream. Near the property’s edge was a slight rise in the land, covered with woods and overgrowth. A farmer had once tilled right up the sides of this little hill until erosion rendered the soil useless. This high ground would normally be the site of a subdivision’s best luxury homes. Paul would do things differently, restoring all of the best natural elements and keeping them open so that they might be shared by future residents. To do so, he needed to group the houses in carefully arranged clusters set within the open spaces.
Before getting the approval to build in this way, Paul had to educate members of the township board. The normal zoning regulations mandated homes on large two-and-a-half-acre lots, requiring them to be spread thinly over the site with little regard for the lay of the land. Paul, however, is putting eighty homes on half-acre lots, small enough to allow thirty-four acres of open space on the site. The homes will be grouped in clusters, yet each will open upon vistas of woods or prairie fields.
After a careful and time-consuming restoration of the land, the building of homes finally began last summer at Canterbury Lakes. The houses are set closely along two roads that make swooping curves in and around open fields. The roads are narrower than standard subdivision roads to limit the spread of concrete. New residents will have made a trade-off: they will gain less private space for themselves but live in the presence of fine restored natural spaces.
When Paul looks out on the site he has designed he remarks that conservation design can remake suburban areas into beautiful places. He says the next time he gets a hundred acres to build upon, he will congregate structures on just thirty of the acres and leave the rest for open space. He envisions building, by the same process, on 600 acres some day, and creating a community in contact with the natural world. He imagines a place that provides homes for residents of all backgrounds and income levels while providing irreplaceable environmental services to the region. He comments, "people here are not buying a lot in a subdivision, but a way of living. They are buying into the uniqueness of this place."
Paul and a handful of like-minded developers are purveyors of a new and innovative strategy for suburbia called conservation design. Conservation design is a method for preserving natural features of an environment, including water. It demands a slowing down of the development process for careful consideration of the land and natural features of each site. It treats each piece of land as a special project, looking beyond the marks of recent farmers to see where original features can be at least partly restored. Only after this first phase of observation and restoration does the building of homes begin. In the process, conservation developers provide homes that open to wonderful landscapes shared by a whole community. Residents can go out in evenings to enjoy walks in neighborhoods that are placed amid the rejuvenating presence of woods, streams, and restored prairie fields.
What Conservation Design Conserves
Conservation design will make some great suburban subdivisions, and if adopted on a wide scale it will turn new suburban areas into a rich quilt-work of homes and high quality open land. Yet its potential transcends aesthetics. Conservation design holds forth the possibility of environmental sustainability for the whole metropolitan region. Its promise comes from its inherent link with one of nature’s most powerful and ubiquitous forces in the midwestern landscape, namely, water. Conservation design adapts suburban development to a natural way of handling water. It does so by reviving the land’s capacity to hold water, cleansing storm water before returning it to underground sources in the earth.
The blueprint for each conservation development is different, as each conforms to a unique piece of land. Yet the underlying principle is the same for all: to restore and reinvigorate a natural flow of water. Essentially, this requires reducing the hard surface cover which is so typical of suburban development. The square miles of concrete and lawns that now spread outward from metropolitan centers create huge areas of hard surface that block the earth’s absorption of storm water. The soil below suburbia is densely compacted and made nearly impenetrable. Conservation developments overturn the standard pattern by limiting the impervious surfaces. The land is left open, the ground shaped into swales and fields that are replanted in deep-rooted grasses of native prairie.
There are specific measures required to turn a residential subdivision into a conservation development. Homes are set closely together in clusters, leaving acres of natural lands around them. At Mill Creek, a spacious development now rising amidst the farm fields of central Kane County, homes are arranged in rows along curving roads that reach in sweeping arcs around open spaces. As at Canterbury, the roads are narrower than in standard subdivisions, and their curve allows each house a wide angle for spacious views. They overlook meadows and woods and a bubbling creek that was cleaned and restored to a meandering prairie stream. Yards around the homes are small, reducing the extent of hard compacted soil covered by lawns. In another area, groups of homes congregate on the perimeter of a large golf course. At one point a stately avenue breaks off toward a public plaza replete with gazebo. This street will hold both homes and stores, enhancing Mill Creek as a place where community life occurs in shared public and natural spaces.
Conservation developments create systems of storm water management that are wholly integrated into the landscape. Prairie Crossing, near the edge of the region in the northern part of Lake County, is a square mile of land with just one-third of the site developed for homes. They cluster in numerous configurations to form domestic spaces in the midst of a vibrant ecology of prairie fields. An encircling border holds 150 acres of farmland dedicated to organic crops. In the development’s center lays a small lake surrounded by prairie. There are few curbs and gutters on the site to catch rain runoff. Instead, storm water that falls on the land flows slowly from streets and small lawns, through swales, prairie fields, and wetlands, following a cleansing sequence before reaching the lake. Although the lake is the final destination of storm water, the process by which water arrives there leaves it clean enough for kids to swim in.
Conservation developments usually center around watersheds or other natural areas that absorb storm water runoff. At Coffee Creek Center, in Chesterton, Indiana, a 200-acre watershed preserve is protected forever by special covenant. What was degraded cow pasture six years ago is now transformed into prairie fields and woods along a small stream, Coffee Creek, which flows northward toward Lake Michigan. This site will have intensive development, with 1,200 residences and a million square feet of commercial/office space filling in around the watershed preserve. Yet no excess storm water will flow off from it. Only now is construction of the buildings underway, after a lengthy process of land restoration that began four years ago.
Some of the best locally based ecologists and landscape designers came together to work the land’s restoration at Coffee Creek. Professionals from Conservation Design Forum and J.F. New and Associates gradually arranged the many built and natural elements of the mile-square site to recreate the land’s original belowground water flow. The eroded banks of the stream were carefully healed, while fields were planted in prairie grasses and woods were cleared of non-native trees so that oaks, hickories, beech, and maples would again flourish. Paths were laid to provide for future residents’ jaunts into the watershed preserve. Long pipes, called level spreaders or "leaky pipes," were laid below just an inch of soil to carry storm water from the settled areas out to the lush mix of soil and grasses in the watershed preserve. The community will contain a wide variety of home types to accommodate a diverse population of residents spanning all stages of life, from seniors to young families. The residents around the creek will live on land made vibrant again by restoration of natural processes that cleanse water and return vitality to the land. In an early sign of success, the salmon of Lake Michigan have begun to swim again up the small creek.
When conservation design extends from storm water to wastewater, it gives even deeper ecological integrity to a residential site. This occurs at Tryon Farms, a new conservation community in Michigan City, Indiana. The development sets apart three quarters of its land in open space, with capacity to accommodate storm water flows and wastewater. There are no sewage pipes going off from Tryon Farms to a city treatment plant, but amidst the expanses of prairie grass are small, specially constructed wetlands called cells. These are treatment areas for wastewater, fitting very nicely in the natural surroundings.
Each is about forty by forty feet in size, and a group of them is built for the four residential areas within the site. Wastewater goes from homes into this system and releases its toxins through the natural action of aquatic plants and bacteria. The cells bloom profusely with vegetation in summer. Their water, cleansed after about seven days (more slowly in winter) returns to the ground or goes to irrigate surrounding hay fields. It is a system that brings conservation design full circle, extending its capacity to recycle water made dirty by humans as well as by rainstorms.
In all of these places a natural process replaces artificial ones whenever possible. Water of all kinds is treated as a resource, rather than a waste material, and the natural lay of the land garners respect and assistance. Conservation designers take time to observe their sites, to know the land features and soil types that will be given over to woods and fields. They understand that they hold the power to restore the vital flow of water that once characterized the whole midwestern landscape.
The Trouble With Water
Long ago, before settlement of the prairies by Europeans, the region’s hydrology, its flow of water, occurred largely underground. Rainwater penetrated through the prairie’s deep-rooted grasses to find hidden seams and vents in the earth. These, in turn, allowed a slow seepage to lakes and streams. The process was in such balance that streams remained at fairly constant levels throughout the year, in wet seasons and dry.
The land’s ability to hold water was marvelous, until farming began and cities arose. Prairies were shorn and wetlands were drained and filled — and their water holding capacity was lost. Now water is intercepted by roads and parking lots, kept on or near the surface of the land and channeled away to retention ponds, lakes, and streams. The entire process of nature is disrupted. Here, where we receive about thirty-five inches of precipitation a year, myriad problems result. Storm waters cause severe erosion as they surge into streams during wet seasons; floodwaters rise faster and higher; valuable groundwater sources are threatened. Storm runoff is contaminated with urban chemicals, harming native plants and aquatic life and causing tremendous loss of biodiversity.
Little has been done since settlement of the prairie to repair the situation. Suburban towns try to alleviate the danger of flooding by putting in infrastructure for improved drainage and storm water detention. Still, an average of $39 million in flood damages is incurred each year in the metropolitan region. According to Dennis Dreher, director of the natural resources department at Northeastern Illinois Planning Commission (NIPC), "storm water detention will greatly decrease the rate of runoff, but not the volume of water. Downstream, at some point, we’ll still see more flooding." The problem is stated succinctly by Tom Price, an environmental engineer at Conservation Design Forum: "It’s the fallacy of flood control, that we want water to go away rather than accommodate it. But with flood control measures alone, Mother Nature will come back to bite."
As development continues, a new specter arises, one that could ultimately prove much more costly than flooding. Groundwater in aquifers has become a critical need for subdivisions on the edge of suburbia, as new suburbs will no longer receive the water of Lake Michigan. The Chicago region already has overdrawn its share of water from the big lake, according to international treaty. So new suburbs will have to rely on local aquifers, although their extent and quality is not fully known. It is known, however, that the shallow ones must be recharged by clean rain that enters through the ground. Currently, however, the hard surfaces and compacted soils of suburban development block the water needed to recharge shallow aquifers. The water that does arrive — coming off the pavements above — may carry ruinous pollution.
Dan McGrath, an environmental economist at University of Illinois in Chicago, believes that water is the great environmental challenge for the region. Yet we hardly value it, giving little heed to the future value of unknown groundwater supplies. All the while, the suburbs continue spreading outward. It is often claimed that the current form of development is the most cost-effective; that it allows homes to be built at affordable prices for more people. Yet the full long-term cost is not known, in part because the real value of water is not sufficiently taken into account. If the damage done to water supplies proves severe in future years, then the cost of suburban development will rise precipitously. Indeed, development in its current form will come to a halt.
"If we can know the full value of each drop of water that falls to the ground," says McGrath, "then we’ll be better able to know the true cost that suburban development imposes. We’ll know what local governments should charge for land conversion and groundwater use. Higher water prices should encourage innovation in residential development practice and water use efficiency." What concerns him is that presently we neither know the full value of water nor have a strong understanding of the long-term reliability of supply. McGrath is trying to find out, building economic models of regional development that better account for the values associated with the natural system itself. While few other economists are doing this here, he states that, "My strong suspicion is that we are seriously undervaluing water resources. When the costs associated with water are fully accounted for, then environmental sustainability is more likely to result. All the other pieces should fall into place, including how we design suburban sites. I think water is the linchpin of sustainable development practice in this region."
Can Conservation Design Happen?
Conservation design promises to get the ancient hydrological process working again. It holds power to redress many of the profound environmental problems facing northeastern Illinois, if implemented on a broad scale. So it may reasonably be asked, why are there so few of these developments around? Well, for one thing, they are somewhat expensive, at least in the short run. Restoring watersheds and prairie fields, limiting hard surfaces, and clustering homes require extra care, which add up-front costs for developers. Over the long term the natural infrastructure of a conservation development will provide great cost savings, because the natural, rather than engineered, infrastructure will maintain itself to a great degree. But the up-front costs are daunting.
One way to help make the practice more widespread is to prove that it works. Mike Sands, environmental manager at Prairie Crossing, can demonstrate the effectiveness of that conservation development. He makes measurements of water flowing off the site. The lake the development created at the site’s center receives all storm runoff, and Mike has regularly gone down to the large pipe below the lake to measure the off-flow. He’s found the flow of water leaving the site to be quite moderate, far below that which comes off a standard subdivision. This remarkable result means that the design is working, that the earth is absorbing much of the runoff, allowing groundwater sources to gain a recharge of non-polluted water.
McGrath, for one, would like to see more scientific measurement of conservation design techniques. Otherwise, he fears, these sites risk becoming secluded enclaves for the affluent with little real environmental benefit. Sarah Nerenberg, an engineer at NIPC, agrees, stating that "hydrology is the key to real conservation design. Just leaving trees and open spaces around homes is not enough.... Natural storm water treatment design must be put into place for it to be authentic."
Nerenberg put together a Conservation Development Evaluation System. Its purpose is to encourage developers to think about conservation design principles early on in the process, before construction begins. It is a kind of ranking system, awarding points according to the extent to which the main principles have been implemented (actually, it awards one to four leaves, with a four-leaf stamp of approval given to a development that earns 80 percent or more of the points). The main criteria include site design (percent of impervious surface, preservation of natural features), storm water management (runoff rate and runoff volume, as measured), management of open space, and protection of natural resources (vegetation and landscaping). She sees a continuum among conservation developments, with sites achieving greater or lesser results according to the extent that developers implement the basic principles.
Most suburban developers today have neither the time nor the capital backing required to build a place like Coffee Creek Center. Still, some are gradually moving in that direction, putting in a few of the basic components during site construction. While they are not taking hydrological restoration to the extent of Mill Creek, they are taking some time to observe a site’s natural setting and arrange homes according to the lay of the land. Few are making the swales and natural drainage systems found at Prairie Crossing; they still rely upon retention ponds and curbed streets with sewers. But they are clustering homes and allowing fields and woods to stand. They are responding to buyers’ demands for open space and the presence of nature near their home sites. In future years such efforts should grow to encompass the full principles of conservation design, in order to sustain the suburban landscape for future generations living in northeastern Illinois.
Resources
Canterbury Lakes, Green Garden Township (Will County, Illinois); ALPS Development Company, 708-534-5664
Coffee Creek Center, Chesterton, Indiana; Lake Erie Land Company, 219-395-5300
Conservation Design Forum, Inc., 375 W. First St., Elmhurst, Illinois 60126; 630-559-2000, info@cdfinc.com
J.F. New & Associates, 708 Roosevelt Rd, Walkerton, Indiana 46574; 219-586-3400
Mill Creek, Kane County, Illinois; Shodeen Inc., 630-232-8570
Northeastern Illinois Planning Commission, 222 S. Riverside Plaza, Suite 1800, Chicago, Illinois 60606; 312-454-0400
Prairie Crossing, Grayslake, Illinois; Prairie Holdings Corporation, 847-548-5400
Tryon Farms, Michigan City, Indiana; Tryon Farm Institute, 800-779-6433
For more information on the Conservation Development Evaluation System , contact The Conservation Fund, 30 W. Monroe St. 18th Fl., Chicago, Illinois 60603; 312-332-6292