NORMAN — Native plantings, wildlife habitat and rippling waters aren’t just descriptors of a country life anymore. In Norman, green infrastructure practices are bringing the beauty of nature to the urban setting but repurposed to do the work that cement and rip rap used to do.
“Even in an urban environment, we can have a natural wetland. We don’t have to mow everything down,” City Engineer Scott Sturtz said.
Using a low impact development approach reduces development-related impacts on water resources and also saves money.
The Brookhaven Creek project is one example. Leveraging $150,000 in grant funding from the Oklahoma Conservation Commission, Norman invested $100,000 and in-kind services worth $50,000 as a matching contribution.
The city planted 200 trees and 600 other plants. Education is part of the process. Often residents will ask why the center portion is not mowed. Established natural wetlands help slow down storm water to protect stream banks from erosion. Those native plants also work to filter out pollutants such as excess nutrients — for example, phosphorus — and keep them from entering the Lake Thunderbird watershed.
Green infrastructure also creates recreational opportunities such as trails along the city’s creeks.
The Brookhaven Creek project included the construction of basins, wetland plantings, Newberry riffles and stream crossings. Newberry riffles use rocks to slow water down and prevent erosion.
“In the long run, for the health of the stream and the area, I think it was a good investment,” Sturtz said.
These “soft armory techniques” are less costly than concrete and result in a savings of 20 to 50 percent.
“When we did the Brookhaven project, we literally had to train the contractors,” O’Leary said. “When the industry catches up, we’ll see even more savings.”
Other innovations the city is looking at using includes log veins which help deflect the water from hitting the bank. The city’s new storm water engineer, Joe Wellingham is looking at using them for some future projects. The logs run at odd angles to bank.