Small Municipal Separate Storm Sewer System (“MS4”) Controls Get Tightened Up in new PAG-13 -- March, 2012

Small Municipal Separate Storm Sewer System (“MS4”) Controls Get Tightened Up in new PAG-13

John R. Embick, Esq. -- March, 2012

I’ve written several times earlier about the manner in which the U.S. Environmental Protection Agency (“USEPA”) and the Pennsylvania Department of Environmental Protection (“PaDEP”) have been moving to require additional controls on stormwater runoff discharges from municipal storm sewer systems (the appropriate term is “Municipal Separate Storm Sewer System”, or “MS4s”).  Many municipalities, if they are located in an urbanized area, are now required to obtain National Pollution Discharge Elimination System (“NPDES”) permits for the discharge of stormwater from municipal storm water collection systems.

These stormwater discharge controls originated with the amendments to the federal Clean Water Act in 1987, and were imposed in a series of phases, which included controls on MS4s.

In order to moderate the administrative burdens associated with developing and reviewing the many MS4 applications for NPDES stormwater permits, EPA allowed states to develop general permit applications for MS4 stormwater discharge permits.  Basically, if a municipality commits to follow the precise provisions and requirements contained in the general permit, then a stormwater discharge permit is issued without an individual review.

Municipalities that need MS4 NPDES permits are currently operating under a general permit (if that municipality is eligible for the general permit), known as PAG-13.  Existing PAG-13 was due to expire in 2010, but has been extended to 3/15/2013.  The extension of the existing PAG-13 was necessary while PaDEP and US EPA negotiated over the terms and conditions of a new PAG-13.

These talks concluded successfully, and on 9/17/2011 PaDEP issued the new PAG-13.  If a municipality thinks it is eligible for coverage under the new PAG-13, then the last date to file a “Notice of Intent” to claim coverage under the new PAG-13 is 9/14/2012.   Do not miss this deadline.

The new PAG-13 tightens MS4 storm water discharge controls in our opinion.  Please also remember that the obligation to develop and implement stormwater discharge controls is an unfunded mandate and it is up to the municipalities must find a way to fund and implement these controls.

What is new or improved in the new PAG-13?

-A written stormwater management plan is required (in the existing PAG-13 this was denominated a “stormwater management protocol”).  The SWM plan must adopt 6 Minimum Control Measures (“MCMs”) and must achieve reductions to the Maximum Extent Practicable (“MEP”) in various categories of discharge parameters.  The MCMs include the relatively new post construction storm water management (“PCSWM”) permit requirement for new development and redevelopment.  Municipalities still do not have to comply with “numerical” discharge standards, and the measures they must comply with are commonly  known as “narrative” measures. 

-If the MS4 discharges to impaired waters which are the subject of a “Total Maximum Daily Load” (TMDL”), permit, then the MS4 operator must develop and include a written MS4 TMDL Plan.   The TMDL Plan must be “designed to achieve pollutant reductions consistent with the conditions and assumptions of the WLA in the approved TMDL permit”.  A series of Best Management Practices (“BMPs”) (i.e, porous pavement, raingardens, etc.) must be used in order to demonstrate compliance. 

-If the MS4 seeks coverage under the new PAG-13, the municipality will need to adopt a revised municipal stormwater ordinance (the model ordinance is attached to the PAG-13).  This may involve amendment and modifications to existing ordinances.

Why is all of this necessary, since most rainfall is “pure?”

After stormwater (virtually any kind of precipitation) falls on the earth, a portion of  it generally flows directly into rivers, lakes and streams. On its journey, everything that stormwater touches or collects from the land surface, roadways, sidewalks, parking lots, construction sites, business parks, etc., is carried to gutters, stormdrains, canals, drainageways, and finally ends up in rivers and streams, without treatment.  Accordingly, a significant portion of contamination in waterways is the result of stormwater runoff.  This is also generally referred to as non-point source pollution (even though most MS4 discharges eventually come from a pipe).

The problem with non-point source pollution is that it is very expensive to collect, treat and discharge. Treatment facilities would have to be very large to treat peak storm flows and would sit unused much of the time.

Accordingly, an efficient and economical way to improve stormwater quality is to treat stormwater at the source and avoid contaminating the stormwater in the first place. Methods to do this have been developed and they are generally referred to as Stormwater Best Management Practices (“BMPs”).

Therefore, EPA and PaDEP contend that MS4 discharges are a part of the waterway contamination problem and need to be controlled. 

Many of the uncertainties regarding the new PAG-13 have been cleared up.  However, a big unknown relates to the next PAG-13 (which will be a requirement in five years or so).  USEPA was to issue a revised or new Stormwater Rule in late December, 2011 (the existing Storm Water Rule Phase II rule was issued on 12/8/1999).  The rule has not been issued as yet.  We expect that the new Stormwater Rule will spell out what additional controls USEPA thinks are necessary to further document and control reductions in MS4 discharges.  Municipal solicitors, please stay tuned.