News and Press

All News

More Tweets

State Beach Season Passes
Air Pollution Control Preconstruction Permits
Air Pollution Control Operating Permits
Freshwater Wetlands
OWTS (Septic) Permitting
OWTS (Septic) Licensing
Stormwater Permitting Info
All Other Water Permits
Aboveground Storage Tank Registration
Underground Storage Tanks
Permitted Waste Transporters
Online Hunting/Fishing/Boating
Rec Freshwater Fishing Licenses
Rec Saltwater Fishing Licenses
Marine Fisheries License Renewals
Shellfish Harvester Certification
Boat Registration Renewal
Berthing & Land Management Customer Portal
Online Renewals/Fee Payments
Agriculture Product Permit Renewals
RIPDES Permit Annual Fee Payment Service
Hazardous Waste Transporter Permit Renewals
Medical Waste Generator Registration
UST Registration Renewal
Marine Fisheries License Renewals
Dental Amalgam Containing Mercury Waste Recycling Annual Report Form
Online Permit Searches
OWTS (Septic) Permits
Wetlands Permits
Water Quality Certifications / Stormwater Permits
Multi-Sector General Permits
Non-Contact Cooling Water Permits
Remediation General Permits
Other Resources
Application Forms
Permit Application Center
Request a File Review
Rules and Regulations

RIPDES Stormwater Industrial Activity

Background and Regulatory Authority

On November 16, 1990, EPA issued the National Pollutant Discharge Elimination System (NPDES) Phase I stormwater regulations that required owners or operators of specific categories of industrial facilities, which discharge stormwater directly to the waters of the United States or indirectly through a separate storm sewer system via a point source conveyance, to obtain a NPDES stormwater permit.

Rhode Island has been delegated by EPA and is authorized to issue individual or general permits under the Rhode Island Pollutant Discharge Elimination System (RIPDES) Program to cover discharges of industrial stormwater. In 1993, the RIPDES Program developed a statewide baseline general permit to cover all stormwater discharges associated with industrial activity, excluding discharges from construction sites. RIPDES re-issued this permit in 1998 and 2003. In 2006, the RIPDES Program issued the first Rhode Island Multi-Sector General Permit (MSGP) to cover stormwater discharges associated with Industrial Activity. The MSGP was re-issued in 2013 and on May 3, 2019.

Who Needs a RIPDES Industrial Stormwater Permit?

Owners or operators of specific categories of industrial facilities, which discharge stormwater directly to the waters of the State or indirectly through a separate storm sewer system via a point source conveyance, are required to obtain authorization of their discharges under the RIPDES MSGP. Ten major categories of industrial activities have been designated as requiring permit coverage. In general, the 10 categories of industrial activities are as follows:

  • Category One (i): Facilities subject to federal stormwater effluent discharge standards in 40 CFR Parts 405-471
  • Category Two (ii): Heavy manufacturing (for example, paper mills, chemical plants, pretroleum refineries, and steel mills and foundries)
  • Category Three (iii): Coal and mineral mining and oil and gas exploration and processing
  • Category Four (iv): Hazardous waste treatment, storage, or disposal facilities
  • Category Five (v): Landfills, land application sites, and open dumps with industrial wastes
  • Category Six (vi): Metal scrapyards, salvage yards, automobile junkyards, and battery reclaimers
  • Category Seven (vii): Steam electric power generating plants
  • Category Eight (viii): Transportation facilities that have vehicle maintenance, equipment cleaning, or airport deicing operations
  • Category Nine (ix): Treatment works treating domestic sewage with a design flow of 1 million gallons a day or more
  • Category Eleven (xi): Light manufacturing (For example, food processing, printing and publishing, electronic and other electrical equipment manufacturing, and public warehousing and storage)

Permitting Options

Owners and operators of regulated industrial facilities have the following options to obtain permit coverage or be exempted from permit requirements if the industrial stormwater operations are not exposed to stormwater:

  • A. General Permit (Multi-Sector General Permit)- The 2019 Rhode Island Multi-Sector General Permit for Stormwater Discharge Associated with Industrial Activity prescribes one set of requirements for groups/sectors of Permittees. The Best Management Practices used to meet the requirements of the permit can be tailored to the specific conditions of the facility. A Notice of Intent (NOI) serves as the application for the General Permit. The operator must electronically submit the NOI and Storm Water Management Plan using EPA's NeT. Note: Industrial stormwater discharges owned or operated by municipalities are also eligible for permit coverage under the General Permit for Small MS4s and Industrial Activity at eligible facilities operated by regulated Small MS4s.
  • B. Individual Permit - The Individual Permit provides the owner/operator of a regulated facility with the opportunity of seeking coverage with a Stormwater Management Plan tailored to their needs.
  • C. Conditional "No Exposure" Certification - Industrial facilities can certify that their industrial materials and operations are not exposed to stormwater, these facilities are excluded from RIPDES industrial stormwater permit requirements provided that the operator submits electronically a "No Exposure Certification" Exclusion.
  • D. "No Discharge Certification" – Industrial facilities generating storm water associated with industrial activities that is not discharged to waters of the State are not required to obtain permit coverage. Facilities which are not required to be permitted must either be: (1) engineered and constructed to contain all storm water associated with industrial activities from discharging to waters of the State, (2) located in basins or other physical locations that are not hydrologically connected to waters of the State, or (3) have all stormwater associated with industrial activity discharged via Combined Sewer Systems. Facilities claiming No Discharge may submit electronically a "No Discharge Certification"

For more information, email: Margarita Chatterton


Templates & Forms

Guidance and Compliance Assistance


Related Links

Frequently Asked Questions
+ Permit
Do I need a RIPDES MSGP?

You are required to apply for permit coverage under the MSGP if you are an operator of a regulated industrial activity (Appendix B, page 127, ver.5/3/19) in Rhode Island that discharges stormwater associated with industrial activity via a point source to waters of the State.

How do I know if I discharge to an impaired waterbody?

You can use RIDEM’s Environmental Resource Map

  • 1. Select “Surface_Water” from the Layer List, on the right.
  • 2. Using the street address locator and zoom tool zoom in to the area in the vicinity of your industrial facility and receiving water body.
  • 3. Click on the first surface water body that stormwater first discharges to. Please note:
  • 3.1. Information regarding the receiving water body will be shown in a pop up box, such as: the name of the water body, water body ID (WBID) number, list of pollutants causing impairment (Impairments) “TMDLs_For,” which either include the parameters for which a TMDL has been approved by EPA or an “x” indicating that a TMDL has not been completed.
  • 3.2. The receiving water body may not have a waterbody ID in which case you need to determine the nearest downgradient waterbody with a water body ID and use the impairment information provided for the nearest downgradient waterbody with a water body ID.
  • 3.3. The receiving water body may not have a waterbody ID and the receiving water body is not hydrologically connected to a water body with a waterbody ID in which case you need to identify the receiving water body as unnamed and not hydrologically connected to a waterbody with a water body ID.

Any further questions, contact Margarita Chatterton at

I do not have a permit, how do I apply?

Submit a Notice of Intent (NOI) electronically on EPA’s NeT program service, please see our Electronic Reporting Page for instructions.

What is a DMR?

DMR is an acronym for Discharge Monitoring Report. These reports are required for most RIPDES permits, and reflect the sampling you performed to maintain permit compliance. These reports must be submitted electronically through EPA’s NetDMR program service.

Other regulated businesses near me do not have a RIPDES permit. What will DEM do?

If you feel that there is a facility that should have a permit, but does not have a permit, a complaint can be filed by calling DEM at 401-222-1360 or 401-222-3070 (after hours).

Is pressurewater wastewater from boat washing covered under the Multi-Sector General Permit (MSGP)?
No, wastewater from boat washing is not considered an allowable non-stormwater discharge under the MSGP (see Part 1.B.2.a. of the 2019 MSGP) if chemicals, soaps, detergents, hazardous cleaning products (such as those containing bleach, hydrofluoric acid, muriatic acid, sodium hydroxide, nonylphenols), steam, or heated water is used and/or it is used to remove topside or bottom paint; marine growth, or other potentially hazardous materials from vessels. Please see additional DEM guidance for more information.

Do I need to conduct inspections if I have authorization under the MSGP?
All facilities authorized under the 2019 MSGP must conduct quarterly routine inspections and stormwater visual assessments twice January 1-June 30 and twice July 1-December 31. The results of the assessments and inspections should be kept with the facility’s SWMP. Please refer to the MSGP Record Keeping and Reporting Template for more information.

What is a No Discharge Certification (NDC)?
In cases when stormwater runoff is retained on-site or discharges to a combined sewer system, the facility can submit a No Discharge Certification (NDC). The certification can be filed electronically on EPA’s NeT program service. Please see our Electronic Reporting Page for instructions

How do corrective actions apply if I exceed benchmarks?
Please refer to the Corrective Action flow chart for more information regarding the corrective action requirements outlined in the 2019 MSGP.

+ DMR Reporting
Where do I report my data?

All facilities with monitoring requirements need to use EPA’s NetDMR program service to submit their discharge monitoring reports (DMRs) electronically.

What should I do if I'm having problems with NetDMR login/data entry/search?

Please refer to the FAQs below and the NetDMR User Guide before contacting the RIDEM. If your problem remains unresolved, please contact the EPA HelpDesk at 1-877-227-8965 or for further assistance.

Why is my NetDMR access pending?

You requested access to your permit in NetDMR, but our office has not received your signed NetDMR Subscriber Agreement (SA). This will still show as pending in NetDMR, and you cannot submit your required DMRs until we receive and approve this document. To print a copy:

  • 1. Sign in to CDX, click your role (Permittee(signature)) and then click “Continue to NetDMR”.
  • 2. Click on “My Account” at the top of the screen in NetDMR
  • 3. Click on the printer icon under the subscriber agreement column.
  • 4. Print your subscriber agreement from NetDMR and sign it and mail it to Crystal Charbonneau, RIPDES Permitting Program, 235 Promenade Street, Providence, RI 02903

Once received, we can approve your request and you can begin submitting DMRs electronically.

What does Value1/Value2/Value3 mean?

These values correspond to potential permit limits in other RIPDES permits. FOR MSGPs, you only need to enter data under the Value 1 column.

My notes say that you do not want < values entered for non-detect results and want us to enter zero. Is this correct?

Yes. Report the Method Detection Limits (MDLs) as a table in a cover letter and attach it at the bottom of the DMR webform entry screen. Please review the RIPDES DMR Instructions.

Do you want lab reports attached?

It is not required, but you can do so. You must report results directly in the NetDMR webform. All lab reports are required to be maintained by the Permittee for a minimum of 5 years and be made accessible upon request.

: I have met my benchmarks. How do I notify RIDEM?

If you have met benchmarks, you still need to submit a DMR, but instead of a data point, you will need to report a No Data Indicator (NODI=A “General Permit Exemption”) code. Please refer to the RIPDES DMR instructions for more information.

My result is a Greater Than value. How should I report?

Please review the RIPDES DMR Instructions.

Bacteria (i.e., fecal coliform, total coliform, enterococci, etc.) monthly average and weekly average results shall be calculated using the geometric mean. If any of the sample measurements are reported as “too numerous to count”, or “TNTC”, the permittee shall report a value of 24,000,000 as the daily maximum value and shall use a value of 24,000,000 for this sample in the geometric mean calculations. It is the permittee’s responsibility to ensure that a sufficient number of dilutions are used to allow the measurement of the actual bacteria concentration. If any of the bacteria concentrations are reported as TNTC, a detailed explanation of the TNTC result, including the dilutions used in the testing, must be submitted with the DMR cover letter.

If Greater Than (>) values were received for other pollutants, they should be reported as such on the DMR, and a detailed explanation of the result(s) should be reported in the cover letter you attach to the DMR.

Can I use one cover letter for all of the sampling points or do you want a specific cover letter for each sampling point?

If you have multiple outfalls, you can create one cover letter per monitoring period and attach it to the first outfall (001) DMR submission.

Would an explanation of ND results in the comments be preferred over a cover letter?

No – a table in the cover letter is required.

What should the cover letter say?

The cover letter is an opportunity for you to document and relay important information to your permit writer regarding permit violations, corrective actions, Minimum Detection Limits, explanations for reporting NODI code(s), etc.

Who is the Principal Executive Officer?

This is the signatory. He/she will have to sign in and submit the final DMRs once the data has been entered.

Our signatory left the company. What should I do?

If there has been a personnel change, the person responsible for signing and submitting DMRs and other Permit submissions must create a CDX account and obtain the authorization by the appropriate Official to electronically sign these documents. Additionally, a certified letter stating the change in the company’s/entity’s cognizant official must be sent to the RIDEM. Refer to your RIPDES permit, RIPDES Rule 12 and the Electronic reporting webpage for more information.

For wastewater treatment facilities: We have a new town manager/city councilor. Do I need to get re-authorized as a NetDMR signatory?

No. Your Subscriber Agreement with the town manager/city councilor’s approval at time of authorization will suffice.

What is the Form NODI section?

NODI stands for No Data Indicator. If you have numeric results for each parameter, you do not need to put in a NODI code. If you do not have data to report, please choose from the NODI codes listed in Section 6 of the RIPDES DMR Instructions (page 3, Rev.2/21/17)

I sampled more than my permit requires. Should I change the frequency of analysis?

If you are collecting more frequently than your permit requires, you must report all results as instructed, and adjust the frequency of analysis to match the actual sampling performed for that monitoring period. If you disagree with the permit requirements displayed in NetDMR, please contact the RIPDES Data Steward at

What, if anything, are you looking for in the comments (sample date, discussion of benchmark exceedances, etc.)?

Instead of using the comments section, DEM recommends putting any information in a cover letter and attaching it to your submission. To do so, click the “Add Attachments” button.

Should we attach a cover letter to one or all of the DMRs being submitted this monitoring period?

Yes, please attach a cover letter to one DMR each monitoring period.

Who will see my DMR data?

Information submitted through NetDMR is generally updated on a weekly basis on EPA’s public interfacing Enforcement and Compliance History Online website, or ECHO.

+ Sampling
Where do I take a sample?

You must collect samples at outfalls discharging stormwater associated with industrial activity identified in your NOI and mapped in your SWMP you submitted when you applied for your permit, unless the outfall has been identified as a substantially identical outfall in your NOI and SWMP. For helpful sampling videos, please see Minnesota’s Industrial Stormwater website.

What are my outfalls?

Refer to your SWMP that you submitted when you applied for your permit. Contact Margarita Chatterton at if you have any questions regarding outfalls and SWMP submissions.

What should I do if my outfalls have changed and I do not see them in NetDMR?

If your outfalls have changed, you should contact Margarita Chatterton at You may be required to submit a new SWMP for the permit file. The SWMP and map must be amended to correctly identify, describe the new outfalls, catchment areas and show the locations of the outfalls. Any changes discussed should ultimately be reflected in NetDMR. If there are any discrepancies between your permit requirements and NetDMR, please contact

What should I do if I don’t see all of the parameters my permit requires?

If you disagree with the permit requirements displayed in NetDMR, please contact

We completed the annual sampling in the first quarter of the year. There was no discharge in some of the outfalls at that time. Is checking these outfalls for flow during the four quarters of visual assessment enough?

If during all four quarters of visual assessment there is no flow at an outfall then can we submit a NODI=C (no discharge) result for that outfall? All required monitoring must be performed on a storm event that results in an actual discharge from the site (“measurable storm event”) that follows the preceding measurable storm event by at least 72 hours, and samples must be collected within the first 30 minutes of the measurable storm event or as soon as practicable. The facility should make all reasonable efforts to take a representative sample for all its outfalls over the course of the monitoring period. The responsible person from the site who is familiar with its storm water management plan should be assessing the storm water outfalls during potential sampling events to determine when the outfalls have actual flow conditions.

The permittee will have to determine what size storm event results in discharges at the different outfalls. When submitting the DMR that reports that there was not a discharge at an outfall please submit as part of your cover letter a statement that indicates that the largest storm events that occurred during the monitoring period did not result in a discharge from the outfall reported as no discharge.