A proposal to revise Montgomery County's Drainage Criteria Manual was deferred at the Aug. 27 Commissioners Court meeting after drawing criticism during a public hearing on the item.
The proposed revision would discontinue allowing flood routing studies to be performed instead of the detention requirements for developments in Montgomery County. The revision would apply to developments with drainage studies received after Sept. 1, meaning developers intending to use just the flood route studies would have to actually use the detention requirements set for developments by the county.
This comes as the county is waiting for the Texas Water Development Board to finalize an upper watershed study by the San Jacinto River Authority, the city of Conroe and the county, along with a regional dredging study also in progress that the county is working on with nearby entities, including Harris County.
During public comment, residents and professional engineers spoke out against the revision, asking for more information to be made available publicly for the engineering community to further review.
David Vogt, the principal engineer at Vogt Engineering, said the item in question would remove a tool developers and engineers use to manage floodwaters, and updating the rules due to growth and urbanization should take more time, consideration and public collaboration.
"I believe that the engineering community should have a chance to look at this and speak with the engineering department, and I think it should be considered more," Vogt said. "I don't know that this absolutely should not be done, but this has been a tool to see in many cases that we don't increase the peak by detaining the wrong place in the watershed."
Resident Jeffrey Miller, who lives in Elm Grove Village in Kingwood, said he suffered during the catastrophic May 7 storm and is in favor of the revision.
"I've come to the conclusion lack of retention reduces flooding. ... I've heard in some cases ... flooding studies can be deficient due to they don't consider accumulative effects on other developments; they can be based on outdated hydraulic studies," Miller said. "I urge you to do away with this loophole."
Montgomery County Engineer Jeff Johnson said some developers and engineers use a strategy coined "beat the peak" to avoid detaining the increased runoff caused by developments. He spoke in favor of the revision.
"I'm opposed to eliminating 'beat the peak,'" Johnson said. "When they say we get all that runoff into the stream, creek, ditch or river before the peak, it sounds great but ... it only works if it quits raining before the peak comes."
Johnson said heavy rain events flood all the watersheds in the county, but the math only accounts for each shed's capacity and not the cumulative that builds up.
"Most developments we do, we require them to route runoff through detention ponds and release at a predetermined rate," Johnson said. "In these cases they're letting the water gush into the streams undeveloped, undetained, and I don't think it's a very good practice; I don't believe it's in the public interest. I think it's hocus pocus; I think it's smoke and mirrors, and I don't believe it for a second."
Johnson said 14 large subdivisions in Montgomery County are allowing "beat the peak," and about 95% of the county's large subdivisions already have detention.
"I don't think there's a person up here who doesn't want to solve this problem right now," County Judge Mark Keough said. "We have other [drainage] studies in the loop right now we've participated in, we're waiting on."
Commissioner Mike Meador said to move forward, the engineering department should gather more input and bring back a viable solution.
"On this end of the county we have a tremendous amount of development going on. People are in the process of doing deals on property," Meador said. "If we change that midstream and the purchasing equation, it may make that subdivision or development not viable anymore."
Meador said he expects figuring out where to put the cutoff to be a problem.
"Where we go is still a work in progress; I don't think we're ready to do that today, to keep in mind how we can cut this off and not affect investors already in the loop," Meador said.