Last Updated 07/28/2026
Excerpt from Arlington Texas Design Criteria Manual
5.10.3. Stormwater Quality Measures
A. Site Layout
While site layout will not give a specific reduction credit, conscientious site layout will reduce the impervious area, thus reducing the post-construction BMP requirements. When the predevelopment grade is steeper than five horizontal to one vertical (5:1) or the site contains natural creeks or wetlands, the site layout shall be designed to require the least modification to the existing topography and drainage. Factors to be considered are lots oriented and designed to minimize change in grade, drainage systems designed to minimize change in time of concentration, and street layouts designed to minimize extents of pavement.
B. Potential Pollutants
Potential pollutants to be treated with post construction BMPs may consist of, but are not limited to the following:
- Total suspended solids
- Increased temperature
- Oil and grease
- Floatables (trash)
- Nutrients (fertilizers)
- Bacteria
- Metals
- Pesticides
- Sediment (soils due to erosion)
C. BMP Selection
Examples of factors that shall be considered when evaluating and selecting BMPs area as follows:
- Effect of the development on runoff volumes and rates
- Potential pollutants from the development
- Drainage area to be treated by the BMP
- Effectiveness of the BMP on potential pollutants from the development
- Natural resources on the site (pre and post construction)
- Configuration of site, including changes to existing waterways.
D. Allowable Post-Construction BMPs:
The following post-construction BMPs may be used. Refer to the NCTCOG iSWM Technical Manual for Site Development Controls or other acceptable North Texas design criteria for detailed design guidance not contained in this manual.
- Bioretention Pond;
- Rain Garden;
- Enhanced Swale;
- Vegetated swale – maximum grade is 2%;
- Filter Strip – at least 20 ft wide with flow spreaders to ensure sheet flow;
- Dry Detention with Forebay (see Stormwater Storage Facility design guidance);
- Retention Pond (see Stormwater Storage Facility design guidance);
- Permeable pavers – designed with an underdrain system and engineered. Design shall address life expectancy, load bearing capacity, soil condition, and drainage
to ensure no standing water; - Infiltration – discharge of roof drains or impervious area to an infiltration trench, soakage trench or planter box;
- Rainwater Harvesting – holding tank for irrigation. Must show irrigation plan utilizing the holding tank;
- Floatables exclusion system – inlet inserts, trash racks, grates on curb inlets installed on private inlets, and designed to account for clogging. Must demonstrate no adverse impacts as detailed in manual if installed on a public outfall. Credit will not be given for grated surface inlets in parking lots unless installed with an inlet insert;
- Subsurface Treatment Devices – oil/water separators, centrifugal treatment devices, and other commercially available devices that are able to treat the design storm without causing structure flooding;
- Natural Area Preservation – can reduce impervious area and count towards postconstruction BMP requirements. This may include preserving, restoring, or creating natural areas and/or riparian areas.
Other post construction BMPs and innovative designs will be considered when submitted with supporting calculations and removal efficiencies in accordance with nationally or regionally recognized design criteria.
F. Construction and Maintenance
The owner shall construct and maintain all post construction BMPs. Ownership and maintenance responsibility of the BMPs are transferable upon the sale of a property. For subdivisions, maintenance may be performed by an association (including home owners associations), but ownership and maintenance responsibility are transferred to each individual property within the association. The plat or separate instrument dedicating the easement shall include a statement of the owner’s responsibility for maintenance; and a Maintenance Agreement shall be filed with detailed information concerning BMP operation, maintenance responsibilities and enforcement actions to be taken if BMPs are not maintained. Standard language for Maintenance Statements and agreements can be obtained from the City.
G. Post-Construction BMP Inspection
The City will inspect the installation of Post-Construction BMPs. The Engineer must submit a letter stating that the post-construction BMPs were constructed as designed. This may be incorporated with the as-built letter for private improvements.
Per the maintenance agreement, the Owner may be required to submit an inspection form to the City on an annual basis as detailed in the maintenance agreement. The City may perform periodic inspections for the purpose of confirming the validity of the inspection reports and ensuring that the BMPs are still functioning as designed. The City may require repair or removal and replacement based on its inspection.
View State Page
Frequently Asked Questions
What post-construction stormwater requirements apply in Arlington, Texas?
Arlington requires post-construction best management practices (BMPs) to treat stormwater runoff from new development and redevelopment sites. These BMPs must be selected to address the specific pollutants likely to result from activities on the site, which can include total suspended solids, oils and grease, nutrients, bacteria, metals, pesticides, and sediment from erosion.
Site layout is also a factor in compliance. When predevelopment grades are steeper than 5:1 or the site contains natural creeks or wetlands, the design must minimize changes to existing topography and drainage. Reducing impervious area through thoughtful site layout lowers the overall post-construction BMP requirement for the site. AQUALIS can help you identify what is required for your specific project before the design process begins.
What types of post-construction BMPs does Arlington allow?
Arlington’s Design Criteria Manual lists the following approved post-construction BMPs. Each has specific design requirements that must be met for the BMP to qualify.
Bioretention ponds, rain gardens, enhanced swales, vegetated swales (maximum 2% grade), filter strips (at least 20 feet wide with flow spreaders), dry detention with forebay, retention ponds, permeable pavers with underdrain systems, infiltration trenches or planter boxes, rainwater harvesting with an irrigation plan, floatables exclusion systems, subsurface treatment devices, and natural area preservation.
Other innovative BMP designs will be considered when submitted with supporting calculations and removal efficiencies consistent with nationally or regionally recognized design criteria. AQUALIS can help you evaluate which BMP type best fits your site conditions and meets Arlington’s pollutant removal goals.
Who is responsible for post-construction BMP maintenance in Arlington?
The property owner is responsible for constructing and maintaining all post-construction BMPs. Ownership and maintenance responsibility transfer automatically upon the sale of a property. For subdivisions, maintenance may be performed by a homeowners or property owners association, but responsibility transfers to each individual property within the association as well.
A Maintenance Agreement must be filed with the City that includes detailed information on BMP operation, maintenance responsibilities, and the enforcement actions that will be taken if BMPs are not maintained. The plat or instrument dedicating the easement must also include a statement of the owner’s maintenance responsibility. Standard language for both documents is available from the City.
Depending on the terms of the maintenance agreement, the owner may also be required to submit an annual inspection form to the City. AQUALIS can manage your ongoing BMP maintenance and inspection reporting obligations on your behalf.
How do I know if my Arlington stormwater system is at risk of failure or safety violation?
Watch for these warning signs.
No Maintenance Agreement filed with the City. Every post-construction BMP in Arlington requires a recorded Maintenance Agreement. If yours was never filed, or if the property changed hands and the agreement was not transferred, that is an active compliance gap.
Engineer certification letter not submitted after construction. Arlington requires the engineer of record to submit a letter confirming that post-construction BMPs were built as designed. If this letter was not filed at the end of construction, the permit closeout may be incomplete.
Annual inspection form not submitted per your maintenance agreement. If your maintenance agreement requires annual reporting and those forms have not been submitted, you may already be out of compliance with the agreement’s terms, which the City can act on during a periodic inspection.
Your BMP is not treating the pollutants it was designed to address. Arlington requires BMPs to be matched to the specific pollutants from your site. A bioretention area that is compacted and no longer infiltrating, a forebay that has filled with sediment, or a floatables system that is clogged is not meeting its design purpose.
Recent property purchase. Maintenance responsibility in Arlington transfers with the property. If you recently acquired a developed site with post-construction BMPs and were not provided the Maintenance Agreement or any maintenance history, AQUALIS can assess the current condition of your stormwater infrastructure and help you confirm what is on file with the City.
The information on this page is provided for general informational purposes only and is not legal advice. Regulations change frequently — AQUALIS makes no warranty as to the accuracy or completeness of this content, and any reliance on it is at your own risk. Consult a qualified professional or your local regulatory authority to confirm requirements applicable to your specific property.
