Underground parking amendment moves forward

Note: Story corrected at 12:05pm

 

Council Member Lee Leffingwell wants to see an environmentally sensitive code amendment that encourages underground parking. Last night, the Planning Commission approved a version of that code amendment with limited discussion.

 

The amendment’s incentive to encourage underground parking is to give a developer the ability to exclude underground parking from a project’s overall impervious cover under a certain set of conditions or circumstances.

 

Environmental Officer Pat Murphy outlined the set of conditions required to exclude the parking from impervious cover limits:

 

·       the underground parking is limited to multi-family or commercial projects in the urban roadway boundary, minus the limited area in the Barton Springs zone;

·       the footprint cannot extend more than 15 percent beyond the building’s own impervious cover limits; the minimum depth of the soil would be two feet, with an average of at least four feet; and

·       the discharge of groundwater from the structure must be managed to avoid adverse impacts on public health and adjacent property.

 

The discussion at the Codes and Ordinances subcommittee of the Planning Commission was more extended than the discussion before the full commission. At that meeting, Murphy explained that the 15 percent limit was intended to limit any excess on underground parking and that the depth was intended to give the encourage the developer to plant trees and shrubbery over the garage area.

 

Commissioners agreed that the ordinance should include an expedited study of the impact of such structures on groundwater. Murphy concurred, saying that it was important to understand how underground structures could affect local streambeds.

 

Murphy said Leffingwell intended to propose a companion resolution to the code amendment to initiate the groundwater study. He will forward the scope of the work and the timeline to the Planning Commission as soon as it is determined.

 

Commissioner Saundra Kirk asked that the groundwater study be expedited so that the amendment could address, if necessary, as soon as possible.

 

Murphy noted, in the subcommittee meeting, that the section about groundwater impacts came out of a current downtown garage that redirected its water flow, in heavy rain situations, into an alleyway behind the building. That kind of situation, Murphy said, should not be acceptable in any future structure.

 

The Planning Commission approved the amendment, 7-0, with Perla Cavazos absent. Environmental Board Chair Dave Anderson said Wednesday when the item came before the board last month, members felt they did not have sufficient information on groundwater impacts and tabled the matter.