The parish is eyeing a low-lying green patch on Lee Drive between Liberty Magnet High School and St. James Place retirement communities, some 200 acres of lowland swamps along Bayou Duplantier. It's also looking at a wooded area along Ward Creek near Highland Road and land in the creek's upper watershed in older parts of Baton Rouge to the northwest.
The projects are still in the early stages and haven't yet involved landowners. But the city-parish has put together nearly $45 million in combined federal hazard mitigation and post-2016 recovery dollars to create or preserve 540 acres of new regional detention and existing floodplain areas across the city-parish.
The city-parish has two strategies. First, it plans to buy land so it can't be developed. New development means new asphalt and concrete, which causes rain to run off instead of being absorbed by the ground.
It also plans to buy land near existing developments to create retention ponds that could ease existing flood problems.
The projects are part of a larger $750 million plan for drainage and stormwater projects in East Baton Rouge.
Flooding has been a top issue since a storm in mid-May inundated more than 1,200 homes in the parish. Some residents have called for a building moratorium, something Ascension and Iberville both implemented recently.
Fred Raiford, the city-parish transportation and drainage director, noted that weather patterns seem to be shifting and severe rains are happening more frequently. So local leaders have to look at ways to adapt.
"Some of these storms, you talk about 50-year storms or 100-year storms, well, they're happening two times, three times a year, and that ain't good," Raiford said. "You've got to look at some ways to reduce the flood risk."
When asked, he said the future detention and floodplain conservation areas could also help reduce the downstream impacts that other planned drainage improvements could have on surrounding parishes.
For example, Ascension and Iberville Parishes have raised concerns about a $255 million U.S. Army Corps of Engineers project to clear and de-snag Ward Creek, Bayou Fountain, Jones Creek and two other waterways in East Baton Rouge Parish. The Corps says the projects will speed up flow in the waterways but won't cause negative effects on the downstream parishes.
What would it cost?
Conserving the land around Bayou Duplantier near Lee Drive would cost $8.5 million. The Ward Creek conservation project, which would seek to buy 140 acres of floodplain just southwest of Airline Highway and on either side of Highland Road, would cost $5.7 million, fact sheets say.
Both are being funded through the $1.2 billion Louisiana Watershed Initiative, Gov. John Bel Edwards' signature, federally funded response to the 2016 floods. An earlier batch of projects from the initiative set aside $5 million to dredge and improve the storm water storage capacity and ecology of the University Lakes near LSU.
The University Lakes empty over a dam into Bayou Duplantier and eventually drain through the 200-acre conservation area being eyed by the city-parish. Part of the Bayou Duplantier conservation project will clear two miles of the bayou's drainage channel, plans say.
Detention and retention ponds, often required by development rules, have become regular features of new neighborhoods and commercial developments in Baton Rouge and other surrounding parishes.
They are seen as a key way to mitigate the increased runoff from the new roads, roofs and sidewalks that replace farm, pasture and woodland.
But regional, public detention areas — either man-made areas or simply conserved floodplains — are emerging as a way to further limit flooding. Both New Orleans and Lafayette governments have been creating water gardens, preserving flood plains, and otherwise using public spaces to hold water.
Even outside the Baton Rouge city-parish government, BREC is trying to build in more stormwater detention features in its latest park improvements at Greenwood Community and Airline Highway parks.
Cheryl Michelet, BREC spokeswoman, said the work will build on past park efforts to hold flood water in the parish. She said BREC parks temporarily held enough water in the aftermath of the August 2016 flood to fill LSU's Tiger Stadium 71 times, according to the agency's calculations.
Melissa Kennedy, a senior project manager with HNTB who is leading the Baton Rouge city-parish's storm master plan effort, said one of the Baton Rouge regional detention projects is a $30 million plan to buy up to 200 acres across several sites in the upper Ward Creek watershed.
Funded through the FEMA hazard mitigation program, the project, unlike the those along Bayou Duplantier or farther downstream on Ward Creek, are designed to improve on existing conditions.
Detention at the upper Ward Creek sites is expected reduce millions dollars in existing flood risk for thousands of older homes in the Baton Rouge area, she said.
As planned, Raiford and Kennedy said, those sites would come in addition to detention ponds that private builders must also create to account for new development and not as a replacement for them.
The city-parish has published a map of proposed sites but has not finalized which ones they will seek to buy.
___
(c)2021 The Advocate, Baton Rouge, La.
Visit The Advocate, Baton Rouge, La. at www.theadvocate.com
Distributed by Tribune Content Agency, LLC.
