Since May, the Super Neighborhood Alliance and the City of Houston were supposed to be discussing changes to Chapter 9 of the City’s Infrastructure Design Manual. We haven’t been.
Instead, we have been discussing one small part, a “fee in lieu of detention” for development and redevelopment of properties less than 15,000 square feet. For reference, that’s approximately a third of an acre and detention is already required by Chapter 9, so a change in this requirement can affect 94% of single family residences. As an elevation challenged city, Houston needs all the detention that it can get, and it needs to be where the new density is occurring, but land to build large regional detention ponds where needed for maximum benefit is often unavailable.
We have proposed an alternative, a single paragraph to the existing wording that permits a fee to be used for under sidewalk detention of up to 15 cubic feet per linear foot of sidewalk. The fee would be paid to the City who would subcontract one of several companies who do this sort of thing. A phone call to the company at the top of a search list resulted in an estimated cost of $5.50-$6.75 per cubic foot of detention. The proposed “fee in lieu of detention” was to have been $7.50 per cubic foot of required detention as calculated by a formula in the City’s Infrastructure Design Manual and didn’t include the cost of a sidewalk. The maximum fee for “under sidewalk detention” would be $5000 for a 15,000 square foot lot. For the City’s average lot of 5,000 square feet, the cost would be $1667.
Under the sidewalk detention provides an immediate solution to rainwater runoff when construction occurs, rather than delaying to gather enough funds to build a regional detention pond. Distributed detention can provide surprising large amounts of detention and it’s located where the detention is needed, so doesn’t need to be piped to the lowest cost land when, and if, it becomes available. And the open bottom system drains water into the aquifer, rather than letting mosquitoes breed as they do in regular storm sewers.
If you think “under sidewalk detention” is a more reasonable alternative than a “fee in lieu of detention” for single family residential properties under 15,000 square feet, please contact your City Councilmember.