The United States has 95,925 industrial facilities currently regulated under EPA stormwater permit programs — auto scrapyards, concrete plants, mines, sawmills, refuse haulers, plating shops and trucking terminals whose runoff is legally allowed to enter rivers, lakes and storm sewers. The interactive map below shows every one of those EPA-permitted facilities across 38 reporting states, plotted directly from the EPA Enforcement and Compliance History Online (ECHO) Industrial Stormwater feed. Click any point for the facility name, address and Standard Industrial Classification (SIC) code, switch to satellite imagery to see what waterway sits next door, or search by business name, city or ZIP.

What This Map Shows

Each blue dot is an industrial site that holds — or has applied for — coverage under either the EPA Multi-Sector General Permit (MSGP) or an equivalent state-issued industrial stormwater permit. Coverage is required because the facility carries out activities (material handling, equipment maintenance, fuelling, scrap processing, mineral extraction, fleet washing) that expose pollutants to rain and snowmelt. Without a permit and a Stormwater Pollution Prevention Plan (SWPPP), the runoff would be an illegal discharge under the federal Clean Water Act.

The map pulls live from EPA’s ECHO public service, so the points reflect the current permittee list rather than a yearly snapshot. Switch the basemap to Satellite in the top-right control to see what each facility actually looks like from the air — and, more importantly, what surface water sits within a few hundred metres of it.

Why Industrial Stormwater Is a Big Deal

The EPA estimates that industrial stormwater is one of the top three sources of surface-water impairment in the United States, alongside agricultural runoff and combined sewer overflows. Unlike a smokestack or a wastewater outfall, a stormwater pollutant load only shows up when it rains: a bare patch of dirt at a quarry, a leaking hydraulic line at a scrapyard, or a fuel-stained slab at a trucking terminal becomes the start of a pollution pulse the moment a thunderstorm hits.

Common pollutants in regulated industrial runoff include suspended solids, oil and grease, dissolved metals (zinc, copper, lead), polycyclic aromatic hydrocarbons (PAHs), nutrients, pH-shifted water and sector-specific chemicals such as cement-process residue, scrap-metal leachate, paint solids and asphalt emulsions. The MSGP requires permittees to monitor for “benchmark” parameters, but the data is self-reported and inspection rates are low — which is exactly why a public locator is useful.

Industrial Stormwater Facilities by State

California alone accounts for roughly 20% of every industrial stormwater permittee in the federal database. Combined, the top five states (California, Utah, Wisconsin, Ohio and North Carolina) hold 47,658 facilities — almost half the national total. The Utah figure is striking given the state’s relatively small economy: it reflects a particularly aggressive enrolment programme by the Utah Division of Water Quality, which captures small construction-aggregate, transport and warehousing sites that other states process differently.

Every state with reportable facility data in the EPA feed, ranked by facility count:

1. California — 19,368 facilities
2. Utah — 10,280 facilities
3. Wisconsin — 7,186 facilities
4. Ohio — 6,496 facilities
5. North Carolina — 4,328 facilities
6. Florida — 3,768 facilities
7. Michigan — 3,680 facilities
8. Pennsylvania — 3,090 facilities
9. Tennessee — 2,970 facilities
10. Mississippi — 2,864 facilities
11. Iowa — 2,552 facilities
12. Oklahoma — 2,373 facilities
13. Illinois — 2,121 facilities
14. Minnesota — 2,084 facilities
15. Georgia — 2,079 facilities
16. South Carolina — 2,049 facilities
17. Connecticut — 1,791 facilities
18. Oregon — 1,533 facilities
19. Maryland — 1,508 facilities
20. Indiana — 1,477 facilities
21. Arizona — 1,401 facilities
22. Missouri — 1,395 facilities
23. Virginia — 1,259 facilities
24. West Virginia — 969 facilities
25. Nebraska — 929 facilities
26. South Dakota — 850 facilities
27. Wyoming — 800 facilities
28. Vermont — 794 facilities
29. Kansas — 763 facilities
30. North Dakota — 641 facilities
31. Washington — 441 facilities
32. Kentucky — 436 facilities
33. Alaska — 401 facilities
34. Delaware — 385 facilities
35. Montana — 342 facilities
36. Idaho — 244 facilities
37. Hawaii — 216 facilities

Thirteen states are absent from the federal feed (Texas, New York, New Jersey, Massachusetts, Alabama, Arkansas, Colorado, Louisiana, Maine, Nevada, New Hampshire, New Mexico and Rhode Island). They administer their own NPDES industrial stormwater programmes and do not currently push facility-level data into the EPA locator — their permittees exist, the data simply lives in a state agency database (TCEQ, NJDEP, NYSDEC and so on). See the data sources section below for more.

Where Industrial Facilities Cluster: Top Cities

San Diego edges out Salt Lake City as the country’s most industrial-stormwater-dense city, with 835 permitted sites. Five of the top ten are in California; four are in Utah and Ohio. The 25 cities with the most permitted industrial stormwater facilities:

1. San Diego, CA — 835 facilities
2. Salt Lake City, UT — 831 facilities
3. Columbus, OH — 748 facilities
4. Ontario, CA — 687 facilities
5. Los Angeles, CA — 673 facilities
6. San Jose, CA — 580 facilities
7. St. George, UT — 527 facilities
8. Tulsa, OK — 524 facilities
9. Portland, OR — 462 facilities
10. Jacksonville, FL — 443 facilities
11. Santa Fe Springs, CA — 422 facilities
12. Oklahoma City, OK — 389 facilities
13. Phoenix, AZ — 356 facilities
14. Fontana, CA — 331 facilities
15. Anaheim, CA — 328 facilities
16. Milwaukee, WI — 321 facilities
17. Memphis, TN — 306 facilities
18. Ogden, UT — 301 facilities
19. Pomona, CA — 288 facilities
20. Charlotte, NC — 275 facilities
21. Cincinnati, OH — 258 facilities
22. Santa Ana, CA — 257 facilities
23. Orlando, FL — 253 facilities
24. Lehi, UT — 248 facilities
25. Oxnard, CA — 241 facilities

Top Industries: Standard Industrial Classification Breakdown

Of the 95,925 facilities in the dataset, 70,579 are reported with at least one Standard Industrial Classification (SIC) code. The top 25 codes account for over a third of all permittees and tell a clear story: the typical American industrial stormwater site is not a steel mill or a chemical plant. It is a scrap yard, a concrete plant, a sand and gravel pit, a trucking depot or a warehouse.

The 25 most common industries among industrial stormwater permittees:

1. SIC 5015, Motor Vehicle Parts (Used) — auto dismantlers and salvage yards — 3,091 facilities
2. SIC 5093, Scrap and Waste Materials wholesale — 3,070 facilities
3. SIC 1442, Construction Sand and Gravel — 3,016 facilities
4. SIC 3273, Ready-Mixed Concrete — 2,030 facilities
5. SIC 4212, Local Trucking, Without Storage — 1,790 facilities
6. SIC 4213, Trucking, Long Distance — 1,637 facilities
7. SIC 4225, General Warehousing and Storage — 1,552 facilities
8. SIC 4953, Refuse Systems (landfills, transfer stations) — 1,308 facilities
9. SIC 1440, Sand, Gravel, Clay and Ceramic Minerals — 1,265 facilities
10. SIC 2951, Asphalt Paving Mixtures and Blocks — 1,155 facilities
11. SIC 3089, Plastics Products, Not Elsewhere Classified — 1,151 facilities
12. SIC 4952, Sewerage Systems — 1,009 facilities
13. SIC 4581, Airports and Flying Fields — 994 facilities
14. SIC 4215, Courier Services Except by Air — 837 facilities
15. SIC 2084, Wines, Brandy and Brandy Spirits — 820 facilities
16. SIC 3714, Motor Vehicle Parts and Accessories — 804 facilities
17. SIC 2421, Sawmills and Planing Mills — 780 facilities
18. SIC 3599, Industrial and Commercial Machinery — 770 facilities
19. SIC 3499, Fabricated Metal Products — 744 facilities
20. SIC 5171, Petroleum Bulk Stations and Terminals — 644 facilities
21. SIC 4231, Trucking Terminal Facilities — 609 facilities
22. SIC 4151, School Buses (depots and yards) — 595 facilities
23. SIC 3471, Plating and Polishing — 594 facilities
24. SIC 3272, Concrete Products — 575 facilities
25. SIC 1420, Crushed and Broken Stone — 564 facilities

The high count of SIC 5015 and 5093 sites (over 6,000 combined) explains why scrap-metal stormwater pollution — in particular zinc, lead and PCB-tainted runoff — has become a flashpoint in EPA enforcement. The aggregate industries (construction sand and gravel, crushed stone, ready-mixed concrete, asphalt) make up another ~8,800 sites and tend to dominate the locator in the western and mountain states. Trucking and warehousing (over 6,000 SIC-coded sites between local trucking, long-distance trucking, courier services, terminals and warehouses) reflect e-commerce and freight growth pushing distribution centres into more communities.

Industrial Stormwater vs Municipal (MS4) Stormwater — What’s the Difference?

It’s worth being precise about what this map does and does not show. The dots are industrial stormwater permittees (Phase I and Phase II MSGP / state-equivalent industrial general permits). They are not Municipal Separate Storm Sewer System (MS4) permits, which are held by cities, counties and transport agencies for runoff from streets, parking lots and developed land — roughly 7,500 MS4 permits exist nationally. They are not Construction General Permit (CGP) sites either; CGP coverage is temporary stormwater authorisation for sites disturbing one or more acres during active construction, and CGP enrolment rotates rapidly. And they are not combined sewer overflows (CSOs), which are releases from older sanitary-sewer systems during heavy rain and tracked separately under the NPDES wastewater programme.

If your runoff comes from a quarry pit, a yard full of rusting cars, a fleet of garbage trucks or a bulk-oil terminal, you’re likely to be on this map. If it comes from a freshly cleared subdivision or a city storm drain, you’re not.

About the Multi-Sector General Permit (MSGP)

The MSGP is the federal blanket permit issued by EPA for industrial stormwater discharges in states where EPA itself remains the permitting authority (mostly Idaho, Massachusetts, New Hampshire, New Mexico, federal facilities and tribal lands). The 2021 MSGP technically expired on 28 February 2026 but remains in administrative continuance until a 2026 reissuance is finalised.

Most operators on the map are not on the federal MSGP — they are on a state-issued equivalent permit. California’s IGP, North Carolina’s NCG general permits, Wisconsin’s WPDES industrial stormwater general permit and Utah’s UPDES industrial general permit are all variations on the same theme: a single permit that covers an entire industrial sector with shared monitoring, inspection and reporting requirements. EPA collects facility-level coverage data from cooperating states, which is why the map reflects 38 states rather than all 50.

Data Sources and Limitations

The point data is read live from the EPA ECHO Facility Finder — State Industrial Stormwater ArcGIS service. The service updates as state agencies push refreshed permittee lists; the EPA does not publish a fixed update cadence.

A few coverage caveats are worth knowing about. Thirteen states are absent or near-absent from the federal feed: Texas (which administers TPDES through TCEQ), New York (NYSDEC), New Jersey (NJDEP), Massachusetts (MassDEP), Alabama, Arkansas, Colorado, Louisiana, Maine, Nevada, New Hampshire, New Mexico and Rhode Island. Permittees in those states absolutely exist — the data simply lives in state-level databases that don’t sync into ECHO at the facility-point level. Texas in particular is worth flagging because most users searching for an industrial stormwater map expect to see Houston and Dallas covered.

Geocoding quality also varies across the dataset. The service includes an ADDRESS_GEOCODE_QUALITY field; some points are rooftop-accurate, others are interpolated from a ZIP centroid. Use the satellite basemap to sense-check before drawing conclusions about a specific site. SIC coverage is partial too: about 26% of records have a null SIC code, and the field can hold multiple codes for diversified facilities, so the breakdown above uses the first reported code only. Finally, the Facility Finder layer does not currently expose the NPDES permit number or the inspection and violation history. For that, query the same facility on EPA ECHO’s main facility search, which links to enforcement records.

How To Use the Map

Find a specific facility

Type a business name, city or ZIP into the search box and press Enter. The map will filter the layer and zoom to the matching points. Click a marker for the facility name, full address and SIC industry classification.

See what’s near a waterway

Switch the basemap to Satellite in the top-right control. Zoom to a point and look for nearby creeks, rivers, ponds and shorelines — that’s where the stormwater goes. Pair this with our interactive US watershed map to identify the receiving water body.

Check your own area

Click My location to centre the map on your address (browser permission required). Pan around to see how many permitted industrial sites operate within a few miles of where you live or work.

Frequently Asked Questions

How many industrial stormwater facilities are there in the US?

The EPA federal locator currently lists 95,925 industrial facilities with active stormwater permit coverage across 38 states. The true national total is higher because Texas, New York, New Jersey, Massachusetts and several other states administer their own programmes and don’t push facility-level data to the federal feed. A reasonable national estimate, including state-administered permittees, is in the 110,000–130,000 range.

Is industrial stormwater pollution legal?

Permitted discharges are legal as long as the operator complies with the conditions of their MSGP or state-equivalent permit — which include implementing a Stormwater Pollution Prevention Plan, monitoring benchmark pollutants, controlling non-stormwater discharges, and submitting Discharge Monitoring Reports. Unpermitted discharges or violations of permit conditions are illegal under the Clean Water Act and can carry civil penalties of up to roughly $66,000 per day per violation.

Why isn’t Texas (or New York, or New Jersey) on the map?

Those states run their own NPDES programmes (TCEQ for Texas, NYSDEC for New York, NJDEP for New Jersey) and store industrial stormwater permittee data in their state databases. The data exists — EPA’s federal locator simply doesn’t ingest the facility points from those state systems. To find a permittee in those states, search the relevant state agency’s database directly.

What does a SIC code tell me about a facility?

The Standard Industrial Classification code is the federal industry taxonomy used by EPA to assign each facility to one of the MSGP industrial sectors. SIC 5015 is auto dismantling, 5093 is metal scrap, 1442 is construction sand and gravel, 3273 is ready-mixed concrete, 4212 is local trucking, and so on. The code determines which sector-specific monitoring requirements apply and what benchmark pollutants the operator is expected to track.

Can I report an industrial stormwater violation?

Yes. EPA accepts public tips at echo.epa.gov/report-environmental-violations. You can also contact your state environmental agency directly. Photographs of visible discharge to a waterway, especially during or after rain events, are particularly useful.

Where does the runoff actually go?

For most industrial sites the runoff drains to either a municipal storm sewer system (which discharges untreated to the nearest receiving water body) or directly to an adjacent stream, river, lake or coastal water. Switching the map to satellite imagery and zooming in is the fastest way to identify the likely receiving water for any specific facility. Our watershed map shows the full hydrologic unit each facility drains to.

Related Water Quality Maps on MapScaping

Industrial stormwater is one piece of a larger water-quality picture. If you’re investigating a particular area or pollutant pathway, the US Tap Water Quality Map shows 44,000 community water systems with EPA Safe Drinking Water Act compliance status, useful for tracing what happens downstream of an industrial discharge that contaminates a source water. The PFAS Contamination Map covers per- and polyfluoroalkyl detections in US drinking water by utility and state, and many PFAS plumes originate from industrial stormwater pathways at airports, plating shops and firefighting-foam sites. The US Superfund Sites Map tracks the EPA National Priorities List of contaminated sites; several of the SIC categories above (scrap, plating, petroleum bulk) overlap heavily with Superfund-listed properties. For pollutant-pathway analysis, the interactive US watershed map shows HUC-level watershed boundaries you can combine with the stormwater map to identify which sub-basin a permittee discharges to, while the live stream gauge map exposes real-time USGS gauge data that helps interpret flow conditions when a stormwater event happens. Finally, the North America Pollutant Release Facilities Map covers TRI, NPRI and RETC pollutant releases at the facility level, complementary to the permitted-discharge data shown here.