Stormwater Master Plan


The City’s Stormwater Master Plan will update the previous Drainage Master Plan that was completed in 1994. This plan will update hydrologic and hydraulic models, analyze drainage complaint areas, assess creek erosion, establish a capital improvement plan as well as assess regulatory options and drainage utility review for funding opportunities.

                                     Stormwater Master Plan Open House Presentation

Efforts to optimize activities with the Habitat Conservation Plan (HCP), Water Quality Protection Plan (WQPP), Watershed Protection Plan (WPP) and the Municipal Separate Storm Sewer System (MS4) will also be incorporated. The plan will consider current and future development and the City’s drainage improvements that have been installed since adoption of the Drainage Master Plan.

Basic Services for the Comprehensive Stormwater Master Plan update will include the following:

1. Review and analysis of conceptual options of over 60 drainage problem “hot spots”.

2. Perform 1D/2D modeling on Purgatory Creek and provide options for flood reduction.

3. Finalize a Citywide fee-in-lieu of providing on-site detention facilities for contribution to future regional facilities.

4. Finalize a Stormwater Management Fee within the San Marcos Urban Infill Boundary (UIB) that calculates a fee-in-lieu of providing on-site water quality facilities.

5. Final deliverables to include an updated 10-yr CIP, changes to CodeSMTX that reflects new fee in lieu of detention as well as Stormwater Management Fee, Citywide drainage “hot spots” and concept design remedies.

The City will be provided a completed model which will allow the alignment of flood areas with the newest FEMA map updates.