Innovative land use, such as compact development, can minimize development impact while maximizing potential. “Compact communities can limit or eliminate development in sensitive areas,” says Newland Communities project manager, Ed Timony, “enabling denser development where the topography allows.”  At Newland’s Briar Chapel community in Chatham County, the compact plan for 2,389 single- and multi-family homes allows for some 900 acres — more than 55% of the property — to be set aside as open space.

Careful analysis and identification, up front, enables green developers to see the big picture and design land use plans that are not only beautiful and rich in recreational opportunities but also work hand in hand with a property’s natural ecosystems.

Water, Water Everywhere

The EPA considers urban and suburban storm water runoff to be one of the primary sources for contamination of our nation’s water supply. As rainwater rushes over impervious surfaces, like pavement, driveways and roofs, it picks up contaminants that can include heavy metals, toxic chemicals, organic compounds, pesticides and herbicides, pathogens, nutrients, sediments, and salts. The average modern subdivision covers as much as 40% of its land with impervious surfaces.

In addition, the rapid water velocity promoted by impervious surfaces, along with traditional storm water drainage systems, creates serious erosion problems as well as high levels of total suspended solids (TSS) in water levels. The greatest threat to streambed health — a fundamental link in our water supply — is high sedimentation caused by soil erosion and stream bank deterioration. A single residential community can have enormous impact on water supplies far downstream.

One of the primary goals of a green community is the protection of water quality. Low-impact development seeks to reduce polluting storm water runoff through a host of management techniques. First, streams, rivers and lakes are protected from immediate development impact through vegetated buffers. Storm water velocity is slowed, allowing for natural filtration of sediments and chemicals before they reach these sensitive surface waters. State and Federal regulations apply to these zones of protection,

Reducing impervious surfaces is also a priority with green communities. Roads at Hidden lake were “soft-engineered” without curbs and gutters. Slightly narrower roads and porous paving surfaces for low-use areas such as driveways and parking lots can significantly reduce the overall square footage of impervious surfaces within a community.

At Greenbridge Condominiums, a planned mixed-use development in downtown Chapel Hill, designs call for roof gardens that act as natural filters, recycling rainwater rather than rushing it headlong into storm drains and the nearest stream.

Using the land itself to slow down and filter runoff is a key element of green site planning. “Nature really does a good job at taking care of itself if you let it,” says Newland Communities’ Ed Timoney. “Use what your land gives you — its contours, its wetlands.” Vegetated swails, rather than concrete culverts and pipes, are highly effective at reducing water velocity and promoting natural infiltration.

Encouraging water to sheet over vegetated terrain instead of collecting it into fast-rushing concourses is a highly effective erosion and sedimentation control measure. “Imagine pointing a garden hose with a pressure nozzle down the slope of a hill,” says Medall. “Think of the erosion you create. Now take the nozzle off the hose, and the same water disperses over a larger area, and there is no erosion at all.”

Soil disruption, especially during construction, is a major contributor to erosion and sedimentation. Green communities take special precautions during the construction phase to minimize this impact. Construction entrances are limited and carefully situated to minimize damage. Where soil must be disturbed, sediment traps such as silt fences and temporary rock embankments and slope stabilizations are employed.

Trees and plants, specifically native plants, are yet another weapon in the green developer’s water-protecting arsenal. Foliage serves to help reduce water velocity and healthy root systems are one of nature’s most brilliant erosion-control devices. And as with so many of the guiding principles of green development, conservation of trees and plants not only serve to protect precious water supplies, but also to provide habitat for wildlife shade for energy-saving hot-weather cooling and beauty to open spaces.

A Holistic Approach

True green development considers more than just the land itself; It seeks to reduce a neighborhood’s impact on the environment by a variety of means. Designing compact, walkable and fully functioning communities reduces energy consumption, resulting in less ground-level air pollution and fewer greenhouse gas emissions — as much as 15 tons less carbon dioxide per year for the average family.

“We’re seeing a new market demand for this kind of urban community,” says East West Partners’ Roger Perry. “This mixed use development — It’s really our responsibility to mitigate degradation of the environment, and now people are really ready for it.”  East 54 in Chapel Hill combines a hotel and condominiums with offices, shops and restaurants — all designed under the guidelines of the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) program.

Revitalization of underutilized property is another green-development strategy for reducing environmental impact. Greenbridge Developments, LLC has plans to build two mixed-use towers on a largely abandoned site in downtown Chapel Hill. Infill development like this makes use of existing infrastructure — roads, water, sewer — and is often in close proximity to job centers. “In essence, we are recycling the land,” says Greenbridge Developments, LLC Partner Michael Cucchiara. “And this kind of urban mixed-use re-development, right in the heart of everything, and also close to public transportation, greatly reduces the need to drive a car.”

At Briar Chapel, the 470,000-square-foot town center offers an employment center, services and shopping and dining venues, all integral to this compact community. And green development does not end with the site plan. Community builders like Crescent and Rhein Medall offer a wealth of resources to their builders to help them meet and exceed their developments’ green building guidelines.  Audubon International publishes a Guide for Environmental Stewardship for Homeowners, to help homeowners to practice sound environmental stewardship in their new homes and neighborhoods. (Go to www.auduboninternational.org).

Green communities incorporate water quality monitoring programs as part of their ongoing commitment to minimizing their development’s impact downstream. Stream sources coming into the property are identified, and samples collected both here and on the downstream side, as water leaves the property. As part of the Audubon Signature Properties program, samples are tested four times a year by a third-party lab for differences in color, pH, temperature and turbidity (sediment). “Sometimes, the water coming from a development is actually cleaner than it was coming in,” says Audubon’s Sarah Anderson. These monitoring programs not only ensure that storm water management measures are working, but they also serve to supply useful data for refining such strategies in future developments.

 “Our firm belief,” says Medall, “is that, in the end, preserving trees, conserving open space, protecting watersheds — all of this is not only important to the environment, but also creates real value.”