Moving storm water continues to be BR problem
When a few inches of rain fell Friday evening in the Baton Rouge area, streets flooded. When more rainfall came Sunday afternoon, some parking lots filled up with water and cars crawled along certain roads through the ponding water.
This past weekend is just one example of why almost 70 engineers, planners and area residents came together Monday to start moving forward with better water management practices.
“The citizens of Baton Rouge area are really ready for a more proactive approach,” said Barrett Chaix, coordinator of economic and environmental research with the city-parish Planning Department.
As a speaker at the Building Green Cities Baton Rouge Workshop on Monday, Chaix explained that although there are rules on the books about how development should move forward, the following of those rules and enforcement is far from uniform.
“It is the erosion from development that is one of the major detriments to water quality,” he told the group.
Although progress has been made over the years to curtail sediment runoff from new development which helps clog waterways, there’s still much that needs to be done, he said.
Just to the west, Houston has experienced problems with storm water management over the years because of expanding development as well. Part of the answer, said speakers at the meeting, is in changing the way storm water is managed in the first place.
The conventional model is to develop ways to get any rainfall out of an area and into waterways or storage areas as quickly as possible, said Robert Adair, president of Construction Eco Services in Houston.
However, Houston and the surrounding county have been moving forward with a new approach called Low Impact Development. This approach works to keep water on site and gradually release it back into the drainage system.
This can be done by using vegetated swales or filter strips, permeable pavement, tree box filters or a number of other techniques that can help keep water on site to be released gradually back into the drainage system.
To help encourage innovation and to develop a better idea of what methods would work for their area, this Low Impact Development process is done outside current development codes.
Adair and other speakers said what they’ve been finding in the past several years are not only improvements in storm water management, but in some cases substantial reductions in project costs.
“Two of the oldest engineering firms in Houston have shifted their entire business model to LID,” he said.
Nick Russo, team leader for environmental services in Harris County, Texas, said the county benefits from using LID by needing less land for a project, reduced costs, improved water quality and the number of groups willing to offer support to make a project work.
For example, the county was going to take an existing two-lane road with side ditches and make it into a four-lane concrete road.
They used LID techniques that funnel the water to one side of the road into a vegetative swale that helps retain the water as the plants help to take out water impurities.
The original cost of the project was going to be $18.5 million, Russo said, but by using the LID techniques, that cost came down to $13.8 million.
Much of the cost savings came from not having to move any pipelines and not needing any offsite water detention area.
Although Harris County has had LID criteria only since 2011, it has been able to move forward with projects quickly because of built-in flexibility.
It also has helped that the county and private developers have realized economic benefits from using the techniques, Adair said.
Jeff Kuehny, director and professor of horticulture with the LSU AgCenter Botanic Gardens, said he hoped the workshop will be the first step in getting developers, planners and others involved in looking at similar solutions for Baton Rouge.