What is Impervious Cover

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  • Physical Address
  • Municipal Plaza Building
    114 W. Commerce, 6th Floor
    San Antonio, TX 78205   
  • Mailing Address
  • P.O. Box 839966
    San Antonio, TX 78283-3966
  • Phone
  • 210.207.8022
how will tci determine the impervious area of each benefited property?

TCI has gone through the process of measuring the impervious area of each parcel of land in San Antonio utilizing aerial and satellite imagery, and Bexar County Appraisal District property records. Based on these sources, the impervious area for all existing storm water accounts has been digitized into individual records. Through the use of an interactive map, rate payers can view the amount of impervious area. Through an appeal process, there will be an opportunity to address errors in calculating the impervious area footprint. 

Interactive Impervious Cover Map

Any dispute contesting the amount of impervious area allocated to a given property will be addressed by comparing the digital record of impervious area to actual measurements provided by the rate payer based on the following definition of "impervious cover". 

Impervious Cover – Roads, parking areas, buildings, pools, patios, sheds, driveways, private sidewalks, and other impermeable construction covering the natural land surface (City of San Antonio Unified Development Code, Appendix A – Definitions and Rules of Interpretation).

As impervious areas do not allow water to be readily absorbed into the ground, the larger amount of impervious area on a property, the greater the storm water flow produced from the property into the storm water system.

In all disputes concerning the calculation of the impervious area for benefited property raised by the owner or occupant responsible for paying the Storm Water Utility Fee, the complainant will have the obligation to present evidence to support the dispute, and the Director of Transportation & Capital Improvements (TCI) shall make the final determination based on applicable law, regulations, and engineering principles. The TCI Director may delegate this authority to TCI staff.