In December, we told you about a new drainage review plan that the city council will consider at Thursday’s Council meeting (Item #37) to exempt development from drainage regulations. A planning commission version and a staff version will be presented to the council.
Proper management of increased stormwater flow is critical to preventing localized flooding. If the City Council adopts the Staff proposal, neighborhoods will have greater exposure to lot-to-lot flooding.
Under the Council proposal, for residential infill, a developer does not have to comply with Section 25-7-151 89 (Stormwater Conveyance and Drainage Facilities) but only provide a “drainage plan” showing that water will run into the right of way or an existing city drainage system. There are no requirements to control peak flow rates.
Even CodeNext provided that “[a] development application may not be approved unless the proposed development reduces the post-development peak flow rate of discharge to match the peak flow rate of discharge for undeveloped conditions as prescribed in the Drainage Criteria Manual.” Section 23-10E-3010 (A)(5)(f).
To justify removing drainage rules, staff contends that the “[p]roposed Code amendments to drainage regulations may reduce up to 40% of total project costs.” [link] Even with the qualifier of “may,” the projected savings of “forty percent of total project costs” is an extraordinarily overblown estimate of drainage regulation costs in the vast majority of cases according to professionals in the industry.
Shockingly, the Planning Commission desires to go even further than the staff, wanting to eliminate drainage review and on-site water detention on residential sites of up to 1.5 acres with up to 16 units. There is no consideration for drainage protection even in city-recognized localized flooding areas or the Austin FEMA flood plain maps.
“Staff does not recommend eliminating all drainage review for such a broad category of development because the resulting runoff could negatively impact surrounding residents by increasing instances of lot-to-lot flooding and, for projects exceeding one acre, strain the capacity of local drainage systems. Additionally, staff believes the Planning Commission proposal would result in a lower level of drainage protection in Austin than any other major Texas city.”
Although Section 11.086 of the Texas Water Code allows someone to sue in court for damages if their property is damaged by water overflow due to diversion from another property, enforcement of proper drainage should not be shifted to neighbors.
Please urge the Austin City Council to reject the proposed changes. Instead of making development more profitable for infill stakeholder developers, consideration should be given to communities experiencing localized and riverine flooding.