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What is a SWP3 in Texas?

A SWP3 (stormwater pollution prevention plan) is the written plan TCEQ's Construction General Permit TXR150000 requires for construction that disturbs one acre or more, or is part of a larger common plan that will. It describes the site, the pollutants it could release, and the best management practices (BMPs) that will control them, and it must be prepared and put in place before soil is disturbed. TCEQ

Last reviewed October 19, 2026. Prepared by our team led by Mohamed Elansary, PhD. We are not a licensed engineering firm and do not seal plans. General information, not legal advice; the permit text controls.

When it is due

The SWP3 must be prepared before you obtain authorization under the permit and implemented before construction that disturbs soil begins. TXR150000 Part III.C TCEQ defines commencement of construction as the initial disturbance of soils from clearing, grading or excavation, or other construction-related activities such as demolition, grubbing, stockpiling fill or placing raw materials. TXR150000 Part I.B

Who needs one

Disturbed area	TCEQ class	Key obligations
Under 1 acre, not part of a larger common plan of 1+ acres	Not regulated by the CGP	No CGP coverage needed. TCEQ
1 to under 5 acres (or part of a common plan in that range)	Small construction activity	SWP3 before work; post Form 20963 at least 2 days before work; copy to MS4 operator 2 days before; no NOI. TXR150000 Part II.E.2
5 acres or more (or part of a 5+ acre common plan)	Large construction activity	SWP3 before coverage; primary operator files NOI in STEERS before work; post Form 20961 or 20962. TXR150000 Part II.E.3

What a SWP3 must contain

Part III.F of the permit lists the minimum contents. In summary:

Site or project description: nature of the work, potential pollutants and sources, schedule or sequence of soil-disturbing activities with start dates and durations, total acres and disturbed acres (including support activities), and soil or discharge-quality data. TXR150000 Part III.F.1
A general location map and detailed site map(s) showing property boundaries, drainage patterns and slopes before and after grading, disturbed areas and phasing, all controls and buffers, stabilization areas, support activities, nearby surface waters (including wetlands, and whether they are impaired), discharge points to waters or an MS4, vehicle wash areas and exits onto paved roads. TXR150000 Part III.F.1(f)-(g)
Names of receiving waters, a copy of (or link to) the permit, and the NOI and acknowledgement (large sites) or the site notice (small sites and secondary operators). TXR150000 Part III.F.1(i)-(k)
A description of BMPs with the timing or sequence of installation: erosion control and stabilization practices, sediment controls, permanent stormwater controls and other required controls such as tracking, materials storage and velocity dissipation. TXR150000 Part III.F.2-4
Consistency with approved local sediment and erosion plans, maintenance requirements, dewatering evaluations, and inspection procedures. TXR150000 Part III.F.5-8

TCEQ's free template, RG-639 (May 2023), organizes these into sections: general site information, schedule of major grading activities, acreage and soil type, location and site maps, support activities, authorization documents and certifications, BMPs and sediment controls, allowable non-stormwater discharges, inspection personnel, dewatering evaluations, inspections of all controls and adverse conditions. RG-639 contents

Where it is kept

The SWP3 is kept on site, or if the site is inactive or has no place to store it, a posted notice must say where it is. It must be readily available during an on-site inspection to TCEQ, local agencies that approve erosion or grading plans, local officials and the MS4 operator. If kept off site it should generally be available within 24 hours of a request. An electronic SWP3 is allowed if it is readable like paper, legally valid and immediately accessible to an inspector. TXR150000 Part III.D.1

Keeping it current

You must revise the SWP3, including the site map, within 7 days of a significant change in design or operations, changed site conditions (new plans, operators or BMPs), or inspection results showing it is not working. TXR150000 Part III.E

How long to keep records

Keep a copy of the SWP3, reports, the site notice and NOI data for at least 3 years from the date the NOT is submitted (or from when coverage ends for sites that do not file an NOT). TXR150000 Part VII

What this page does not cover

Industrial (multi-sector) stormwater permits, MS4 permits, city or county grading permits, and sites outside Texas. It does not replace reading TXR150000.

Have it written for you

SWPPP Desk prepares site-specific SWPPPs from your drawings for construction sites in the states we cover (coverage by state), for a fixed price, delivered the next business day after your inputs are complete. Small site (1 to under 5 acres): $449. Large site (5 acres or more): $749. Background: all guides.

Small site: $449 Large site: $749