SW

Stormwater Directory

City of Harlingen

City of Harlingen Public Works / Engineering

CityMS4 Phase IIVerified 2026-03

Local Permit / Authorization

Permit Required
Yes
Permit Name
Grading / Drainage Permit
Submit To
City of Harlingen Public Works / Engineering
Lead Time
Plan review typically 2–4 weeks
Application Method
Submit via City of Harlingen Building Department at 118 E. Tyler Ave., Harlingen, TX 78550 or contact city engineering
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 Harlingen Drainage Design Criteria; flat RGV topography requires pump-assisted drainage in low areas
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-, and 100-year storms per City of Harlingen Drainage Design Criteria; Rio Grande Valley irrigation canals and the Cameron County Drainage District system are interconnected with urban stormwater
Turbidity Standard
No numeric NTU limit; discharges must comply with TCEQ TXR150000 and not degrade Arroyo Colorado or Rio Grande water quality

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. Harlingen is in Cameron County in the Rio Grande Valley. The Arroyo Colorado — a natural Rio Grande distributary — flows through Harlingen and is classified as an impaired waterway by TCEQ (TMDL for bacteria). The interconnected irrigation and drainage canal system in the RGV creates a complex drainage environment. Hurricane season preparedness is important in this coastal-adjacent region.

Local Inspection Requirements

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

Special Overlay Zones

Arroyo Colorado (Impaired Waterway)
Trigger: Development draining to the Arroyo Colorado
Restriction: TCEQ has established a TMDL for bacteria in the Arroyo Colorado; enhanced pathogen and pollution controls required; Arroyo Colorado is a state priority water quality concern for the Rio Grande Valley
Cameron County Irrigation / Drainage Districts
Trigger: Development in areas served by Cameron County Irrigation Districts (CCID) or Drainage Districts
Restriction: Cameron County Irrigation Districts control the network of canals that serve dual irrigation and drainage purposes; outfall connections to irrigation or drainage canals require district approval; do not introduce sediment into irrigation canals
FEMA Special Flood Hazard Area
Trigger: Development within FEMA-mapped 100-year floodplain
Restriction: Floodplain development permit required from City of Harlingen Floodplain Administrator; no net fill without compensatory storage

Design Manual

Manual Name
City of Harlingen Drainage Design Criteria

Jurisdiction Notes

Harlingen is a commercial hub city in Cameron County in the Rio Grande Valley, home to a major VA hospital, South Texas College of Law, and significant retail and medical industry. The city sits on the Arroyo Colorado, which is impaired for bacteria and subject to a TCEQ TMDL. The RGV's flat topography and interconnected irrigation/drainage canal network create a unique drainage management environment. The region is in one of the few areas where agricultural irrigation canals and urban stormwater drainage are directly interconnected.

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 Harlingen Public Works / Engineering and the agency website before beginning construction.