Two news sources out of New Orleans, Louisiana recently published articles on the New Orleans City Council’s new requirement of new pervious pavements throughout the city: Radio.Com article titled “Porous pavement: helping to contend with flooding?”, and a Times-Picayune/New Orleans Advocate article titled “What’s porous paving? All new lots in New Orleans must have in city’s fight with water woes”.
Porous Pavement. Permeable Pavement. Pervious Pavement. Heavy Duty Open Grating—all names for the parking surfaces that the New Orleans City Council in Louisiana has decided for all new pavement parking surfaces … New requirement for parking lots seen as step alleviating flooding?
The use of pervious/porous pavements were first presented over six years ago in the “Greater New Orleans Urban Water Plan”, established in 2010. Porous paving is now required in many suburban developments in the west where drought-stricken cities look to recover as much rain water as possible for recharging aquifers.
New Orleans is a city often inundated by water and, just as often, a city frustrated in its attempts to deal with it. Porous pavement is helping to contend with flooding in New Orleans, and a new requirement for parking lots is seen as step to alleviate flooding. Now, joining a movement that supporters say will help mitigate flooding and soil subsidence, the City Council of New Orleans has decided that all new pavement parking surfaces must bypass the use of asphalt and go with new porous/pervious pavement. The rules unanimously approved by the council in early September 2019, require businesses to use pervious paving— for any new projects. The rules do not require businesses to replace existing concrete lots and do not affect residential construction. The ordinance comes more than a year after amendments to the city’s code that required certain developments to keep the first 1.25 inches of rainfall out of the city’s drainage system during storms.
The goal is to allow rainwater flow through the pavement, to be absorbed by the soil beneath it, instead of running off to an overtaxed storm drain. Doing so will also slow ground subsidence and promote undergrowth to hold the ground in times of heavy rainfall.
Parking spaces must be porous under the new rules, but “driving lanes” in parking lots do not need to be. That’s because heavily traveled parts of parking lots tend to need the heavy-duty support that impervious materials provide. Porous parking surfaces obviously won’t solve the problems of all street flooding in New Orleans, or clear the canals and pipelines that drain the city. But, they will lighten the burden placed on the city’s drainage system during heavy rainfalls and curb stormwater runoff to Lake Pontchartrain, council members said.
Jason Williams, City Councilman, who co-sponsored the ordinance said, “Simply put … water cannot simply be absorbed through traditional pavement and concrete. Permeable solutions … allow water to be absorbed into the ground, reduce runoff volumes, mitigate flooding and reduce subsidence.”
Those solutions include porous pavement solutions that come in differing types. Costs for porous surfaces can vary, ranging from 5 to 10% less than for traditional concrete to 10 to 20% more expensive, according to estimates from city stormwater managers.
According to the National Ready Mixed Concrete Association (NRMCA) “Pervious Concrete Pavement” website, pervious concrete pavement is a unique and effective means to address important environmental issues and support green, sustainable growth. By capturing stormwater and allowing it to seep into the ground, porous concrete is instrumental in recharging groundwater, reducing stormwater runoff, and meeting U.S. Environmental Protection Agency (EPA) stormwater regulations. In fact, the use of pervious concrete is among the Best Management Practices (BMPs) recommended by the EPA—and by other agencies and geotechnical engineers across the country—for the management of stormwater runoff on a regional and local basis. This pavement technology creates more efficient land use by eliminating the need for retention ponds, swales, and other stormwater management devices. For the NRMCA Pervious Concrete Pavement website (includes Applications, Benefits, Construction, Design, etc.), please click on image to the left and see link below.
1 – For an additional ISCP pervious pavements article THIS MONTH (September 2019) that touts the Greater Hyderabad Municipal Corporation (GHMC) launched a pilot project ‘Pervious Concrete Road Pavement’ (PCRP) in India titled “GHMC, India Launched ‘Model Pilot Project’: ‘Pervious Concrete Road Pavement’ at Sports Complex”, please go to: https://www.concretepavements.org/2019/09/20/ghmc-in-india-launched-project-pervious-concrete-road-pavement-near-sports-complex/
2 – For the “Greater New Orleans Urban Water Plan”, please go to: https://livingwithwater.com
3 – For the NRMCA Pervious Concrete Pavement site and Applications, Benefits, Construction, Design, etc., please go to: https://www.perviouspavement.org/index.html
4 – For the article titled “Porous pavement: helping to contend with flooding?”, please go to: https://wwl.radio.com/articles/parking-lots-help-flooding-issues
5 – For the Times-Picayune/Advocate article titled “What’s porous paving? All new lots in New Orleans must have in city’s fight with water woes”, please go to: https://www.nola.com/news/politics/article_534386f6-d31e-11e9-a8f0-dba5c6e48a1c.html