Storm Water MS4 Program

Mason Chesapeake Bay Action Plan

A Total Maximum Daily Load TMDL for the Chesapeake Bay was established by the U.S. Environmental Protection Agency (EPA) in 2010 requiring states and localities to remove specific pollutants from storm water runoff before the water enters local streams and rivers that drain into the Chesapeake Bay. The level of pollutants allowed to be discharged to the Chesapeake Bay is called a Total Maximum Daily Load.

Mason Facilities Management developed a Chesapeake Bay TMDL Action Plan that shows how it intends to meet the first of three milestones: a 5 percent reduction in nitrogen, phosphorus and suspended solids by June 30, 2018. Mason will be required to offset an additional 35% reduction by June 30, 2023, and the final 60% by June 30, 2028.

Mason TMDL Action Plan Mason TMDL Action Plan

Please submit written comments to Jane (Zhongyan) Xu at 4400 University Drive MS 1E4, Fairfax, VA 22030 or

What is an MS4?

The term MS4 is commonly used to describe both:
• The infrastructure used to convey stormwater runoff
• The owner/operator of the infrastructure that is permitted to discharge this runoff

MS4 Program Plan MS4 Program Plan

2016 MS4 Annual Report 2017 MS4 Report

2016 MS4 Annual Report 2016 MS4 Report

2014 MS4 Annual Report 2015 MS4 Report

2014 MS4 Annual Report 2014 MS4 Report

2013 MS4 Report (Revised) 2013 MS4 Report (Revised)

2013 MS4 Report 2013 MS4 Report

According to 40 CRF 122.26(b)(8), municipal separate storm sewer system (MS4) means “a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels or storm drains):

(i) Owned or operated by a State, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to State law)…including special districts under State law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a designated and approved management agency under section 208 of the Clean Water Act that discharges into waters of the United States.
(ii) Designed or used for collecting or conveying storm water;
(iii) Which is not a combined sewer; and
(iv) Which is not part of a Publicly Owned Treatment Works (POTW) as defined at 40 CFR 122.2.”

Controlling the quality of stormwater in urbanized areas has become of greater concern since the issuance of the Clean Water Act (CWA). Despite earlier attempts to address water pollution, it was not until 1972 when the Environmental Protection Agency (EPA) was given the authority to develop and implement a stormwater management program that regulated the amount of pollutants being discharged in U.S water bodies. As part of its stormwater management program, the EPA created an enforcement management mechanism called the National Pollutant Discharge Elimination System (NPDES). With the implementation of the NPDES, it became obligatory for all operators of a Municipal Separate Storm Sewer System (MS4) who intended to discharge stormwater to surface waters to obtain a NPDES permit.  Depending on the size of the municipality, the NPDES issued Phases I and II final rules. Phase I requiring a NPDES permit for medium and large cities or municipalities with populations of 100,000 and more, and the second one requiring a NPDES permit for small MS4(1). In addition, each regulated MS4 is required to develop and implement a program designed to reducing the discharge of pollutants to the maximum extent practicable (MEP)(2), the MS4 program.  Included in their MS4 program, the University is to fulfill the minimum requirement stipulated by the EPA which includes:
MCM1: Public education and outreach on stormwater impacts

The MS4 program at George Mason University (Mason) seeks to alert homeowners, students and staff on the impacts of stormwater runoff on water quality through free training sessions, workshops and the distribution of educational materials. The public outreach program at Mason also provides guidance on how the community can help in minimizing adverse impacts of urban runoff in waterways.

Public Edu & Outreach

For more information, refer to the EPA’s factsheet on
Public education and outreach on stormwater impacts.

• Schedule of events and workshops
EPA’s Printable outreach materials




After The Storm After the Storm
pdficon_small Prevent Stormwater Pollution
pdficon_small Urban RunOff

MCM2: Public involvement and participation

George Mason University encourages residents and students to participate in volunteer programs hosted on campus for the conservation and improvement of water resources. Projects such as the Patriot Pack Out and the Campus Cleanups are conducted every year with the purpose of getting the community involved in the University’s efforts on reducing the amount of pollutant loads in stormwater. Educational workshops and materials, offered by Mason, also provide information to the public about stormwater management practices implemented on campus and different sustainable practices that can help restore and protect our water.

For more information, refer to the EPA’s factsheet on
Public involvement and participation.

What can you do to help? Join some of our projects and programs at George Mason University….

Patriot Pack Out
• Campus Cleanups

MCM3: Illicit discharge detection and elimination

The MS4 program at George Mason University strives to address public and individual concerns on stormwater impacts and encourages the community’s contribution in discovering and reporting possible hazardous runoff.  In order to detect and eliminate both direct and indirect illicit discharges, George Mason University has developed an Illicit Discharge Detection and Elimination Program (IDDE), which relies on the George Mason University’s Illicit Discharge Detection and Elimination Policy to prohibit any non-stormwater discharges into the sewer system or any receiving waterway.  Such policies are enforced by both, Mason LD and the Environmental, Health and Safety Office (EHS), who rely strongly on regular inspections and public notification. George Mason University encourages the community’s contribution in discovering and reporting possible polluted runoff and maintains appropriate staffing to address such reported concerns.  If you would like to report suspected non-stormwater discharges, fill out an Illicit Discharge Report Form , and/or email us at .

Outfall Reconnaissance Inventory is another important component of the IDDE program at George Mason University. The ORI is performed annually in order to identify possible illicit connections and discharges, as well as, to keep track of all existing stormwater management facilities and structures within the MS4. During the ORI, outfalls are also evaluated for structural damages or uncommon conditions that might indicate the present of pollutants.

For more information, refer to the EPA’s factsheet on
Illicit discharge detection and elimination .

In the event of an oil or chemical spill, follow the Oil and Chemical Spill Response Guide or contact the
Environmental Health and Safety Office (EHS)

• Illicit Discharge Ordinance
MCM4: Construction site stormwater runoff control

Under the VSMP permit, George Mason University is required to develop, implement and enforce a program to
reduce the discharge of pollutants associated with construction activity into the MS4. In order to address MCM 4,
the Erosion and Sediment Control and Stormwater Management Programs are integral components of all design,
construction maintenance, and management of the University’s facilities and campuses. In accordance with the following:

(1) The Virginia’s Erosion and Sediment Control Law (§1O.1-560 et. seq.);
(2) The Virginia Erosion and Sediment Control Regulations (4VAC50-30 et. seq.);
(3) The Virginia Erosion and Sediment Control Certification Regulations (4VAC50-50 et. seq.);
(4) the Virginia Stormwater Management Act (§1O.1-603 et. seq.); and
(5) The Virginia Stormwater Management Program (VSMP) Permit Regulations (4VAC5060 et. seq.)

Mason LD has implemented rules and regulations in its ESC and SWM programs, which are enforced during the planning, permitting and construction phase by Mason LD staff. Mason LD personnel receive training by the Department of Conservation and Recreating on Erosion and Sediment Control, in order to enforce such programs.  Certified staff is responsible for reviewing plans during the permitting process and conducting regular inspections of the site during construction. Inspections and Plan review are to be performed in accordance with DCR’s Virginia Erosion and Sediment Control Manual and George Mason University’s Annual Standards and Specifications for Erosion and Sediment Control and Stormwater Management. A copy of the Annual Standards and Specification is available and/or provided upon request. Public concern associated with runoff from construction activity is received via email at or by filling out an Illicit Discharge Report Form.

For more information, refer to the EPA’s factsheet on Construction site stormwater runoff control .
Post – construction stormwater management in new development and redevelopment

The MS4 program at George Mason University consists of minimizing the impacts of runoff associated with land disturbance such as flooding, erosion and water pollution. Due its current developmental expansion, George Mason University’s goal is to find cost-effective alternatives that provide water quantity and quality control while complying with laws and regulations. Current practices implemented by the University in managing and controlling stormwater mainly consist on promoting natural hydrologic processes as well as minimizing contact of pollutants with rainwater.  As land disturbing activities take place, George Mason University incorporates measures that protect and/or improve natural areas during and after construction. In addition to the ongoing efforts to preserve the natural landscape, George Mason University strives to reduce impervious areas as much as possible and create more vegetated regions.
Mason’s Vegetated Roofs:

Mason's Vegetated Roofs
In 2006, George Mason University constructed its first vegetated roof located
on the Fairfax campus, outside of Research I building. The facility covers an
area of approximately 1030 ft filled with a variety of hardy and aesthetically
pleasing plants that seamlessly blend into existing landscaping. The filtration
properties of this facility help to eliminate pollutants while reducing storm
water runoff.

For more information on refer to EPA’s fact sheet on Vegetated Roofs
Porous Pavement at Mason Vale:

Porous Pavement at Mason ValeIn the ongoing effort to reducing impervious areas, George Mason University continues to encourage the implementation of porous pavement. George Mason University currently has more than 1 acre of pervious pavement in Fairfax campus.  Permeable pavement is mainly used in low-traffic areas such as back roads, housing facilities and bike racks. The use of pervious pavement not only reduces the runoff concentrations, but also enhances the natural process of filtration.


For more information on refer to EPA’s fact sheet on Porous Pavement at
Mason Vale

Rain Gardens (Bioretention):

Rain Gardens (Bioretention)
George Mason University has three rain gardens located on north-east portion of the Fairfax Campus. Each rain garden is composed of a variety of native perennial plant species, which require minimal maintenance (wildflowers, shrubs and small trees).  Rain gardens allow the storm water to penetrate into the ground and restore the water table, while simultaneously removing pollutants.



For more information on refer to EPA’s fact sheet on Rain Gardens (Bioretention)

Bio-swales (Vegetated Swales)

There are several vegetated swales which treat, convey and partially infiltrate storm water runoff at different locations of Fairfax and Prince William Campuses. In some cases, these swales are implemented in conjunction with other structures such as check dams, which are used to reduce flow rates of runoff and allow for infiltration, where steep slopes are present.  Such swales are vegetated with water-resistant plants. A variety of small grass swales can also be found on the west side of Fairfax Campus; these work essentially as drainage ditches, but they latently provide more infiltration and pollutant removal. All George Mason University’s existing swales are used mostly as pre-treatment for other existing SWM/BMP facilities.

For more information on refer to EPA’s fact sheet on Bio-swales (Vegetated

Our Ponds:

George Mason University has currently two retention (wet) ponds serving as both storm water management (SWM) and best management practice (BMP) facilities. The first retention pond is located on the south-east portion of Fairfax Campus (Mason Pond).  Mason Pond treats approximately 137 acres, which is equivalent to more than a third of the total campus area. The second wet pond (Prince William Pond) is located on the perimeter of Prince William campus and it treats close to 60 acres of the property; In addition, George Mason University has two existing detention (dry) ponds providing quantity and quality control for stormwater runoff. The first, Krasnow Pond, located at the north-east of Fairfax Campus, treats approximately 8 acres of the campus. The second one, Masonvale pond, is also located at the North-east of Fairfax Campus and it treats approximately 15 acres. Fairfax Campus also relies on an extended detention pond located south-west of the campus known as Braddock Pond. Braddock Pond is used as both quality and quantity control facility which conveys roughly 315 acres of Fairfax Campus drainage water. Braddock pond is a receiving facility for more than half the total stormwater runoff produced in Fairfax campus as it also intercepts water released by the Mason Pond.

For more information on refer to EPA’s fact sheet on Ponds Dry ponds and Wet ponds


Grasscrete are pre-fabricated structure made out of reinforced concrete with voids to be filled with grass.   Grasscrete has been installed as an alternative to ordinary concrete in different locations within Fairfax and Prince William campuses, such as, fire access roads, low-traffic roads, and other areas where emergency traffic is required.  Because its drainage capabilities are roughly the same as regular grass, Grasscrete has been beneficial in George Mason University’s effort to reduce impervious areas.
Pollution prevention and good housekeeping

The operations and maintenance program at George Mason University has a training component focusing on
preventing and reducing the amount of pollutants in receiving waterbodies. Regular construction site inspections,
infrastructure examination as well as environmental compliance assessments are key elements of our in-house
management practices. Other implemented programs that help minimize issues associated with polluted runoff on
campus include our recycling, waste material handling and storage procedures as well as the nutrient management plan.