Is LID Flowing to the Forefront?

If low-impact development sounds like something that’s solely the concern of builders and contractors, engineers and city officials, Daniel Ellis has a different perspective.

“It makes sense here in Northwest Arkansas,” said Ellis, a vice president at Crafton Tull, “because we drink what washes off the parking lots.”

Ellis was referring to the fact Beaver Lake is the source of Northwest Arkansas’ drinking water. That fact makes LID, defined by the Environmental Protection Agency as “an approach to land development (or re-development) that works with nature to manage stormwater as close to its source as possible,” relevant to anyone who gets his water from a local tap.

Steven Beam, also a vice president at Crafton Tull, offered a more expanded definition of LID.

“Primarily, it is aimed at stormwater and protecting water quality,” Beam said. “It can affect every aspect of a project, from architectural design to site development, but its main goal is water quality as it relates to stormwater runoff.

“You’re kind of treating it as it goes through the soil.”

LID, local engineers agree, has been in play for quite a while in some parts of the country, particularly along the east and west coasts. In Northwest Arkansas, however, the philosophy hasn’t taken hold until the last six to eight years.

“It’s becoming much more commonplace, and as we go down the road — I don’t want to predict how far — I think it will become standard industry practice to do things this way,” Beam said.

 

The Old Way

The rise of LID’s popularity has coincided with increased awareness and implementation of other sustainability-driven initiatives. That includes LEED, which stands for Leadership in Energy and Environmental Design, and is a certification process the U.S. Green Building Council uses to ensure buildings conform to its standards in areas such as water and energy use, materials and resources, and design innovation.

“Low-impact development can be a component of LEED in how you develop your site,” Beam said.

Taking environmentally friendly practices into consideration wasn’t always the way business was done. Ellis said such practices simply weren’t discussed when he began working in the industry.

“Bulldoze the land, put up a building, lay asphalt and plant a few trees and shrubs to meet some landscaper’s needs,” he said. “That’s what we did.”

Daniel Barnes, president of McClelland Consulting Engineers Inc.’s Fayetteville office, echoed the sentiments of Ellis in terms of stormwater.

“Years ago, as a civil engineer, our thoughts were, ‘Let’s get it underground as fast as we can, get it in a pipe, get it off-site.’ That was the goal,” Barnes said.

Some of the sea change in respect to more environmentally friendly practices, Ellis said, has been led by school systems and other entities that were building facilities with grants from tax dollars. Later, both Ellis and Barnes said, a business with deep Northwest Arkansas roots became a major champion of sustainable practices, including LID.

Former Wal-Mart Stores Inc. CEO Lee Scott’s “Sustainability 360” speech in 2007 signaled a shift in philosophy not just for its discount stores, but also for other outlets like Neighborhood Market and Sam’s Club. Wal-Mart’s results employing LID principles encouraged its suppliers and others to incorporate some of its practices.

The result, Barnes said, has been increased education in the benefits of LID as more and more entities across the region employ its principles.

“They’ve begun telling their stories and people are finally becoming educated on what this can do,” Barnes said.

 

LID’s ROI

Exactly what LID can do is often hard to measure in a purely economic sense.

“There are a lot of views on that, and you can probably ask 10 different people and get 10 different answers,” Beam said. “You can’t say unequivocally that it’s going to save money on every project … but what it can allow you to do is to reduce the traditional stormwater structures that you have on-site.

“It’s really a site-by-site scenario. More often than not, in my experience, people are not doing it to try to save money. They’re doing it because they feel it’s important to try to develop the property as responsibly as possible as it relates to environmental impacts.”

In the case of Northwest Arkansas Community College’s recently opened Center for Health Professions, implementing LID principles was part of a larger effort. Jim Lay, NWACC’s executive director of construction and facilities planning, said certain energy-efficiency measures have been in use since the school’s inception, but the school is seeking LEED certification for its new $14.2 million facility.

“Sustainability and low-impact development seemed to kind of move into the limelight in the last decade or so, so we thought this would be a good start for us, a learning experience,” Lay said.

“I had read about it … but hadn’t really experienced it firsthand.”

Lay also took a LEED course to beef up on its principles. Several of those are reflected in at least some of the LID work that was done at the center.

For example:

• A concrete parking lot was constructed instead of an asphalt lot, so that heat is reflected rather than absorbed. Concrete also is more porous than asphalt, which allows rain and stormwater runoff to percolate through it rather than flood surrounding areas or storm drains.

• Bioswales were built between the building’s parking lots. They contain a five-layer system that filters water before it reaches storm drains eight feet below the surface.

Ellis worked on the NWACC project, and designed the bioswales. He said they cost more than other options from a construction and labor standpoint, but allow stormwater to be collected and moved to a nearby field.

“We actually took all of our stormwater and put it into an area that needs moisture to be vibrant and survivable. … It’s just sitting there. Either it soaks into the ground or evaporates,” Ellis said.

The concrete parking lot, meanwhile, cost about $300,000 more than an asphalt one, but has its benefits. For one, Ellis said, using concrete instead of asphalt eliminates the possibility of petroleum oils leeching out of the parking lot and into stormwater.

Ellis said such lots also can have more subtle benefits. He used a shopping center with a “vast sea of baking asphalt” and a similar center with a concrete parking lot that also incorporated landscaping and shade trees as an example.

“Where do you want to go shopping?” Ellis said. “There are some benefits there to the customer’s — or whoever is going to use the building — experience from the car to the building.”

Barnes said McClelland’s clients have seemed to take those factors under stronger consideration in recent years.

“A number of years ago, we would bring this up to clients and they weren’t that knowledgeable about it,” Barnes said. “But we’ve seen that turn around to where a lot of our clients come to us now and say, ‘This is what we’d like to do.’

“We’re seeing that evolution, which is a wonderful thing.”

 

Other Projects

Barnes mentioned McClelland’s work at the ongoing Fayetteville High School project as a good example of LID principles being used, and Beam pointed to Crafton Tull’s work at The Vue on Stadium Drive, a nearby apartment complex that will target University of Arkansas students.

Crafton Tull also utilized LID principles at sports and aquatics parks in Rogers. The bioswales and rain garden constructed at the aquatics park were examples of Crafton Tull “trying to use those areas to treat stormwater runoff before it enters the traditional stormwater system, to protect the downstream water quality,” Beam said.

Similar logic was followed when creating bioswales and wetlands at the sports park.

 “They will all help assimilate the fertilizers and things that are going to have to be used on the fields to keep them in good shape, before it gets into Turtle Creek or Osage Creek,” Beam said.

Those kinds of positive impacts on Northwest Arkansas bodies of water, including Beaver Lake, are what should make LID important to more than just contractors and engineers, Barnes said.

“We’re regulated by the health department on our drinking water as far as how we treat it, what limits we can have,” he said, “so anything we can do before it gets there helps.”