SW

Stormwater Directory

City of Conroe

City of Conroe Engineering Department

CityMS4 Phase IIVerified 2026-03

Local Permit / Authorization

Permit Required
Yes
Permit Name
Grading / Drainage Permit
Submit To
City of Conroe Engineering Department
Lead Time
Plan review typically 2–4 weeks
Application Method
Submit via City of Conroe Engineering at 300 W. Davis St., Conroe, TX 77301 or online portal at cityofconroe.org
Fee
Contact agency for current fee schedule

Water Quality Standards

Impervious Cover Limit
No citywide impervious cover cap; drainage systems must accommodate design storm flows per City of Conroe Design Standards; Lake Conroe watershed is a primary water quality concern
On-Site Treatment Required
No
Detention Required
Yes
Detention Standard
Detention required to limit post-development peak flows to pre-development levels for 2-, 10-, 25-, and 100-year storms per City of Conroe Engineering Standards; Montgomery County drainage requirements apply in unincorporated areas
Turbidity Standard
No numeric NTU limit; discharges must comply with TCEQ TXR150000 and not degrade Lake Conroe, San Jacinto River, or Spring Creek

Local SWPPP / Drainage Plan

Local Plan Required
Yes
Plan Name
SWPPP per TCEQ TXR150000; drainage report required for local permit
PE Stamp Required
Yes
Drainage study prepared by a Texas PE required for grading permits. Conroe is the seat of Montgomery County and the city closest to Lake Conroe, a SJRA water supply reservoir. Projects in the Lake Conroe watershed should implement enhanced water quality BMPs. The city is experiencing rapid growth as a Houston suburban overflow market.

Local Inspection Requirements

Requirements
City of Conroe Engineering Department inspects grading permits at rough grading and final stabilization.
Inspector Qualification
No city-specific certification required beyond TCEQ SWPPP requirements

Special Overlay Zones

Lake Conroe Watershed
Trigger: Development draining to Lake Conroe (San Jacinto River Authority water supply reservoir)
Restriction: Enhanced water quality BMPs required to protect drinking water supply; San Jacinto River Authority (SJRA) manages Lake Conroe and may require coordination for projects with significant watershed impact
San Jacinto River Floodplain
Trigger: Development within FEMA-mapped 100-year floodplain along the West Fork San Jacinto River
Restriction: Floodplain development permit required from City of Conroe Floodplain Administrator; no net fill without compensatory storage; USACE coordination required for work in the San Jacinto River channel
Montgomery County Drainage Districts
Trigger: Development connecting to Montgomery County Drainage District maintained channels in or near Conroe
Restriction: Coordinate with applicable Montgomery County Drainage District for outfall connections; district criteria apply for channel connections

Design Manual

Manual Name
City of Conroe Engineering Design Standards

Jurisdiction Notes

Conroe is the seat of Montgomery County and a major growth center north of Houston along the I-45 corridor. The city has experienced explosive population growth as Houston's northern suburbs expand. Lake Conroe is a significant water supply reservoir managed by the San Jacinto River Authority. Montgomery County updated its drainage design criteria after Hurricane Harvey (2017). The city's development is closely tied to Montgomery County's overall growth and the expansion of The Woodlands-area master-planned communities.

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 City of Conroe Engineering Department and the agency website before beginning construction.