Stormwater Atlas

bmps.manufactured

Manufactured / Proprietary Treatment Devices

Approval lists, verification programs, and when MTDs may substitute for GI.

ReviewedPrevalence 48%~289 manuals tagged14 citationsModel: heuristic+editorial
Provisional practice synthesis for discussion — not a design manual or adopted regulation. Controlling state, regional, and MS4 criteria apply when more stringent. Verify citations against the linked jurisdiction manuals.

Practice

Manufactured treatment devices appear in many approved-BMP lists and are commonly conditioned on independent verification (for example TAPE, NJCAT, or state lists). Agencies differ on offline versus online configurations and on whether MTDs may replace runoff-reduction steps.

SCM selection hierarchy

Draft national guidance grounded in atlas practice — not a design manual or adopted regulation.

Hierarchy stepSuggested national guidanceAtlas note
1. Avoid / minimizeReduce imperviousness and disconnect drainage before selecting structural SCMsHierarchy language common in GI/LID chapters
2. Runoff reduction / retentionPrefer infiltration, harvesting, and volume reduction where soils and groundwater allow52% of BMP-list manuals (154)[1,3,4,5,6]
3. Filtration / bioretentionUse bioretention and filtration for treatment when retention is limited43% of BMP-list manuals (130)[1,2,3,4,5]
4. Detention / peak controlUse detention to meet channel and flood criteria after volume and treatment steps61% of BMP-list manuals (182)[1,2,3,4,5]
5. Manufactured treatmentAllow MTDs conditionally with verification-program references; do not bypass hierarchy where infiltration is feasible18% of BMP-list manuals (54)[3,5,6,7,8]

Guidance

  1. 14.1Field-verified

    Allow manufactured devices conditionally with reference to recognized verification programs or state approval lists.[3,1,2,4]

  2. 14.2Editorial

    Size for the water-quality peak or volume per manufacturer and agency rules.[1,2,3,4]

  3. 14.3Editorial

    Do not use MTDs to bypass runoff-reduction hierarchy where infiltration is feasible; prefer verified performance data over marketing claims.[1,2,3,4]

Regional notes

State approval lists differ; some localities ban proprietary devices or require offline configuration.

Open questions

Which verification programs to cite nationally. Offline versus online configurations and bypass design.

References

Numbered footnotes for guidance clauses and atlas notes. Field-verified entries come from structured atlas evidence; corpus-pattern entries are keyword-matched excerpts.

  1. [1]AlaskaAlaskaField-verifiedpp. 180–181
    “Primary Secondary Secondary Secondary Extended Storage Pond High Low Primary Secondary Secondary Secondary Wet Vaults Medium Lowa Primary Secondary Secondary Minor Detention Dry Pond High Low Secondary Minor Minor Minor Oversized Pipes High Low Minor Minor Minor Minor Oil/Grit”
  2. [2]AlabamaAlabamaField-verifiedpp. 18–19
    “3) modification of the surface drainage pattern, including the associated development of stormwater management facilities. Summary of Hazards Associated with Land Development On-site Land development clearly increases potential erosion and sediment hazards on-sit”
  3. [3]MontanaMontanaField-verifiedContents, Chapter 5
    “Infiltration Basin ... Bioretention ... Permeable Pavement Systems ... Dispersion ... Biofiltration Swale ... Extended Detention Basin ... Wet Detention Basin ... Proprietary Treatment Devices”
  4. [4]California Department of Transportation (Caltrans)CaliforniaField-verifiedSection 2.2, Table 2-1, Pages 2-5 to 2-7
    “Caltrans Construction Site BMPs are divided into six categories, as shown in Table 2-1: Temporary Soil Stabilization, Temporary Sediment Control, Wind Erosion Control, Tracking Control, Non-Stormwater Management, Waste Management and Materials Pollution Control”
  5. [5]CaliforniaCaliforniaField-verifiedTable 3-1, Page 3-1
    “Table 3-1 Municipal Fixed Facility BMPs: Non-Stormwater Management, Vehicle and Equipment Management, Material and Waste Management, Building and Grounds Management, Over Water Activities, General Stormwater Management”
  6. [6]ConnecticutConnecticutField-verifiedPage 110-111, Functional Categories of Structural Stormwater BMPs
    “This Manual includes the following major categories and types of structural stormwater BMPs that are recommended for use in Connecticut, based on their primary function: Pretreatment BMPs, Infiltration BMPs, Filtering BMPs, Stormwater Pond BMPs, Stormwater Wetland BMPs, Water Quality Conveyance BMPs, Stormwater Reuse B”
  7. [7]GeorgiaGeorgiaField-verified199
    “Bioretention Basin; Bioslopes; Dry Wells; Infiltration Trenches; Organic Filters; Regenerative Stormwater Conveyance; Sand Filters; and Stormwater Planters/Tree Boxes”
  8. [8]State of Hawaii Department of Transportation, Highways DivisionHawaiiField-verifiedAppendix A, Page v
    “LID TREATMENT CONTROL BMPs: Vegetated Buffer Strip, Vegetated Swale, Enhanced Swale, Infiltration Trench, Infiltration Basin, Bioretention Facility, Permeable Pavement, Pocket Wetland, Rainwater Harvesting, Tree Box Filter”
  9. [9]PennsylvaniaPennsylvaniaCorpus patternpages 300-300
    “COMMON TYPES OF MTDs This Manual addresses the following general types of MTDs: manufactured filters, hydrodynamic separators, micro-bioretention, and manufactured FCDs. Manufactured filters are manufactured devices that contain granulated filter media”
  10. [10]City of DetroitMichiganCorpus patternpages 432-432
    “Stormwater Management Design Manual CHAPTER 14 – Manufactured Treatment Devices14-1 14. Manufactured Treatment Devices This chapter discusses manufactured treatment devices (MTDs), which are proprietary commercially avail”
  11. [11]State of Hawaii Department of Transportation, Highways DivisionHawaiiCorpus patternpages 176-177
    “new or existing drainage structures. These proprietary devices rely on various manufactured processes to achieve the required water quality treatment. A wide variety of proprietary BMPs exist, not all of which could be included here. The designer must”
  12. [12]MontanaMontanaCorpus patternpages 151-151
    “anual September 2017 | A-3 Appendix A – Glossary Proprietary Treatment Devices: Manufactured devices used to treat storm water runoff through various processes which may include sedimentation, filtration, and sorption. These devices can provide treatme”
  13. [13]VermontVermontCorpus patternpages 53-54
    “atment Standards Section 4.0 4.1.5. Proprietary Devices Proprietary devices are manufactured systems that use proprietary settling, filtration, absorption/adsorption, vortex principles, vegetation, and other processes to provide stormwater treatment. T”
  14. [14]ConnecticutConnecticutCorpus patternpages 259-259
    “horus Low Nitrogen Low Bacteria Low Description Proprietary stormwater BMPs are manufactured systems that use proprietary settling, filtration, absorption/adsorption, vortex principles, vegetation, and other processes to remove pollutants from stormwat”
  15. [15]Tennessee Department of Environment and ConservationTennesseeCorpus patternpages 274-274
    “5.4.12 Manufactured/Proprietary Tre Manufactured or proprietary stormwater control measures are absorption/adsorption, vortex principles, vegetation, and oth management requiremen”
  16. [16]District of ColumbiaDistrict of ColumbiaCorpus patternpages 211-211
    “differentiate between a traditional stormwater BMP, a proprietary practice, or manufactured BMP, the term Manufactured Treatment Device (MTD) will be utilized for the class of practices that require an approval from DDOE. DDOE recognizes the value of”
  17. [17]Rhode IslandRhode IslandCorpus patternpages 170-171
    “al when a LUHPPL is present. Figure 6-4 Deep Sump Catch Basin (MADEP, 2008) 6.6 PROPRIETARY DEVICES Many proprietary devices have been developed over the years in an attempt to provide cost-effective stormwater treatment, particularly for retrofit sit”

Supporting jurisdictions

9 jurisdictions cited in this section (outline tags ~289 manuals; full atlas has ~299).

pa-statedetroit-mihawaii-dot-pcbmpbillings-mtvt-statect-statetn-statedc-guidebookri-state