Which Permit Type do you need?

Editor’s note: Welcome to our series on Stormwater Management! We hope you find these PIG-exclusive articles to be helpful in explaining the basics of stormwater regulations and what you can do to help protect your storm drains.

Background on state level permits: In all but four states and US territories, the National Pollutant Discharge Elimination System (NPDES) permit program operates at the state level. When states are issuing these permits, the limitations and requirements are developed to help meet their goals for improving water quality in impaired waters. For waters that currently meet established water quality standards, the goal is to maintain or improve upon those standards.

There are two main types of NPDES permits — general and individual — which we’ll discuss in more detail below.

What is a Stormwater General Permit?

General permits establish the same effluent limitations and requirements for every entity who is eligible to apply for this type of permit. Most states prefer to issue general permits because it helps to simplify and speed up the permitting process. It also reduces the amount of time the state agency needs to spend reviewing the details of individual permits and establishing specific effluent limitations on a case-by-case basis.

Multi-sector General Permits and Construction General Permits are the two most common types of permits issued.

Multi-sector General Permits

States usually group multiple types of industries who are all likely to have a minimal effect on the environment, or those that have processes that generate similar types of pollutants together to minimize the need for facilities to submit individual permit requests.

Because the effluent limitations are the same for all applicants, permittees know the limits that they will need to meet when they submit their Notice of Intent (NOI) and their Stormwater Pollution Prevention Plans (SWPPPs) can reflect specific control measures that will be effective in meeting those limitations.

Construction General Permits

Construction permits are more temporary in nature and the effluent limitations focus on the specific types of pollutants that construction activities generate, such as sediment, oil and grease. States vary on who must apply for construction general permits, as regulations specify that the operator must submit the application. But some states define this as the general contractor, while others say that it is the landowner [40 CFR 122.21(b)].

What is a Stormwater Individual Permit?

As the name implies, individual permits are specific to a single entity. Individual permits are based on the specific types of pollutants that the permitted entity will be discharging and effluent limits in the permit are often different from the requirements of general permits. This can be either an advantage or a disadvantage because the permittee does not know what limits the state will impose before their permit is issued. In some cases, the limits may end up being more stringent than the general permit requirements. In other cases, the permittee may benefit by not having to test their discharges for effluent parameters that they know are not present at their facility.

In some cases, even if a facility submits a NOI and requests an individual permit, the state or permitting agency may choose to cover them under a general permit.

Does My Facility Need a General or Individual Permit?

Facilities may choose to apply for either type of permit, but it is usually more difficult to obtain an individual permit.

  • You may not be able to apply for an individual permit online, whereas general permit applications can often be processed online
  • Individual applications require longer review periods
  • Individual permits are typically more expensive than general permits

General permits are usually issued unless there are specific factors concerning your operations that cause you to fall outside the parameters of the general permitting process. Whenever states or the federal government make an exception, they have to manage that exception individually in addition to everyone else who has a general permit. In most cases, individual permits are issued only if there is a qualifying reason to do so. Some of these reasons include:

  • The state requires you to apply for an individual permit
  • You have an absolutely unique situation that doesn’t fit into the general permitting scheme
  • There is no way that you can comply with a term of the general permit, and you therefore need a variance that an individual permit may provide

The Bigger Picture

Whether permits are general or individual, each permit establishes the specific requirements that must be met to allow the state to meet its water quality parameters. When states issue permits, the pollutants from all entities are considered collectively to ensure that the combined pollutant loads entering each water body are not exceeded. According to the EPA, before the creation of the Clean Water Act in 1972, “only one-third of our waters were considered healthy. Today, approximately two-thirds are considered healthy.”


Keep reading our Stormwater Management Series for more expert advice and storm drain solutions from New Pig.

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