Comal County (Unincorporated)
Comal County Development Services
CountyMS4 Phase IIVerified 2026-03
Local Permit / Authorization
- Permit Required
- Yes
- Permit Name
- Floodplain Development Permit / Drainage Review
- Submit To
- Comal County Development Services
- Lead Time
- Plan review typically 2–4 weeks
- Application Method
- Submit via Comal County Development Services at 150 N. Seguin Ave., New Braunfels, TX 78130 or contact county engineering
- Fee
- Contact agency for current fee schedule
Water Quality Standards
- Impervious Cover Limit
- Significant portions of unincorporated Comal County are within the Edwards Aquifer Recharge Zone or Contributing Zone — EAA permit required; impervious cover limits and water quality controls apply on regulated land; western portions of the county are over the recharge zone
- On-Site Treatment Required
- No
- Detention Required
- Yes
- Detention Standard
- Detention required to limit post-development peak flows to pre-development levels per Comal County Drainage Criteria; applies in unincorporated areas; design must account for Hill Country flash flood risk from Guadalupe and Blanco river watersheds
- Turbidity Standard
- No numeric NTU limit; discharges must comply with TCEQ TXR150000 and not degrade Guadalupe River, Comal River, Blanco River, or Edwards Aquifer recharge features
Local SWPPP / Drainage Plan
- Local Plan Required
- Yes
- Plan Name
- SWPPP per TCEQ TXR150000; drainage report required for county permits
- PE Stamp Required
- Yes
Drainage study prepared by a Texas PE required for development permits in unincorporated Comal County. Edwards Aquifer recharge zone coverage is extensive in western Comal County. The county is experiencing rapid population growth as one of the fastest-growing in the nation. Hill Country terrain creates significant flash flood risk from rapid runoff on limestone slopes. Coordination with Edwards Aquifer Authority is required for recharge zone development.
Local Inspection Requirements
- Requirements
- Comal County Development Services inspects development in unincorporated areas.
- Inspector Qualification
- No county-specific certification required beyond TCEQ SWPPP requirements
Special Overlay Zones
Edwards Aquifer Recharge Zone (Western Comal County)
Trigger: Development on land over the Edwards Aquifer Recharge Zone — primarily the hills and ranches west and north of New Braunfels
Restriction: EAA permit required; impervious cover limited to 15%; water quality controls and karst protection required; karst geology (caves, sinkholes, solution conduits) is prevalent
Guadalupe River Canyon Floodplain
Trigger: Development within or adjacent to the Guadalupe River and its Hill Country tributary canyons
Restriction: Floodplain development permit required; Hill Country canyons can experience extreme flash flooding (wall of water events); standard FEMA methodology may underestimate peak flows in canyon tributaries; conservative design is required
Blanco River Floodplain
Trigger: Development within or adjacent to the Blanco River as it flows through southern Comal County toward Wimberley
Restriction: Floodplain development permit required; the Blanco is among Texas's most flash-flood-prone rivers; conservative freeboard above BFE is strongly recommended
Design Manual
- Manual Name
- Comal County Drainage Criteria
Official Resources
Jurisdiction Notes
Comal County is one of the fastest-growing counties in the United States, driven by the explosive growth of New Braunfels and residential development spreading from both San Antonio and Austin. The county's Hill Country terrain, Edwards Aquifer recharge zone, and flash flood-prone rivers create a challenging stormwater regulatory environment. This entry covers unincorporated Comal County — New Braunfels has its own permit requirements. Canyon Lake (USACE reservoir on the Guadalupe River) is in the western part of the county and provides flood control and recreation, but the Guadalupe below Canyon Lake has experienced major flooding when reservoir flood releases are required.
Remember: These local requirements are in addition to the TCEQ state construction permit. Both must be satisfied before breaking ground.
Disclaimer: This information is provided for general reference only. Always verify requirements directly with Comal County Development Services and the agency website before beginning construction.