City of Austin

Storm Water Management Program - MCM 3: Illicit Discharge

City of Austin Has...

60 Miles of Streams:

  • Cedar River
  • Dobbins Creek
  • Murphy Creek
  • Turtle Creek
  • Wolf Creek
  • Tributaries of these waters (ditches, etc.)

3 Water Bodies:

  • East Side Lake
  • Mill Pond
  • Ramsey Mill Pond

City of Austin Has..

33 Miles of Impaired Streams:

  • Our streams are impaired for
    • aquatic life
    • aquatic recreation, OR
    • aquatic consumption
  • They do not meet water quality standards.
  • They ultimately flow to the Mississippi River.

2 Impaired Water Bodies:

  • Our lakes are impaired due to pollutants.
  • They do not meet water quality standards.

City of Austin Has..

206 Stormwater Outfalls:

  • An outfall is the point where stormwater flows into a water body.

Example of an Outfall

How is stormwater regulated within our community?

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What is MS4?

  • Municipal Separate Storm Sewer (MS4) is any municipally owned stormwater conveyance system (e.g., City roads, ditches, and stormwater pipes). City of Austin has to comply with the NPDES MS4 permit through 6 Minimum Control Measures (MCMs).

MCMs:

  1. Public Education & Outreach
  2. Public Involvement / Participation
  3. Illicit Discharge Detection & Elimination
  4. Construction Site Stormwater Runoff Control
  5. Post Construction Stormwater Runoff Control
  6. Pollution Prevention / Good Housekeeping

Illicit Discharge?

  • An illicit discharge is anything that enters into the storm sewer system (e.g., storm drains, ditches, ponds) that is not entirely composed of stormwater.
  • Storm drains do not flow to the wastewater treatment plant, so any pollutants that goes into the storm sewer system will end up in our lakes and streams.

Example of sediment on roadway

Sediment:

  • This is often the largest and most obvious pollutant load associated with stormwater runoff.

Impacts:

  • Sediment can increase turbidity in waterways, which can harm fish and other aquatic life by reducing food supplies, degrading spawning beds, and effecting gill function.

Illicit Discharge Cont.

Grass Clippings:

  • As waste breaks down in our local waterways it adds excess nutrients such as NITROGEN & PHOSPHORUS to the water.
  • This leads to unwanted & uncontrolled growth of algae and non-native aquatic weeds.

What is so bad about algae?

  • Excess nutrients can lead to high levels of algae growth. Apart from looking unsightly, excessive algae blooms can block out sunlight and deplete the oxygen levels in the water, which can lead to fish kills.

Other Illicit Discharges:

Holes in the bottom of the dumpster.

Motor Oil left on the side of street

Concrete Washout areas directly over storm drain

What you can do:

  • If you suspect an illicit discharge is occurring REPORT IT.
  • Take a photo or record a video, if able.

Who to Contact:

  • Stormwater Specialist - Michael Rask
  • Office Phone: 507-437-9950
  • Email: mrask@ci.austin.mn.us

Major Spills Contact:

  • Local Authorities: 911
  • MPCA Duty Officer: 1-800-422-0798

Example of an Outfall

Example of sediment on roadway

Holes in the bottom of the dumpster.

Motor Oil left on the side of street

Concrete Washout areas directly over storm drain