Collaborative Illicit Discharge Elimination Program (IDEP) — 2025

Background

This Illicit Discharge Elimination Plan (IDEP) for the City of Midland, Midland County Drain (MCDC) Commissioner, Midland County Road Commission (MCRC), and Lincoln Township (collaborative permittees) and has been prepared in accordance with the requirements of the National Pollutant Discharge Elimination System (NPDES) Permit Application for Discharge of Storm Water to Surface Waters of the State from a Municipal Separate Storm Sewer System (MS4). The IDEP is intended to prohibit and effectively eliminate illicit discharges, illicit connections, and illegal dumping/spills to the separate storm water drainage system. The IDEP will focus on storm water outfalls and point source discharges within the urbanized area limits, based on the most current Census Data. All aspects of the IDEP will be documented by action and evaluation methods and recorded within the Progress Report submitted to the EGLE.

• An “illicit discharge” is any discharge to, or seepage into, an MS4 that is not composed entirely of storm water or uncontaminated groundwater except discharges pursuant to a National Pollutant Discharge Elimination System (NPDES) permit. A discharge that originates from the applicant’s property and meets the illicit discharge definition is considered an illicit discharge.
• An “illicit connection” is a physical connection to an MS4 that primarily conveys non-storm water discharges other than uncontaminated groundwater into the MS4; or a physical connection not authorized or permitted by the local authority, where a local authority requires authorization or a permit for physical connections.

No person shall discharge or cause to be discharged into the storm water system, pollutants or waters containing any pollutants, or cause to or contribute to a violation of applicable water quality standards.

Storm Sewer System Map

All storm sewer system data is housed by the collaborative permittees per the table below. These maps can be accessed or viewed upon request.

Procedure for Performing Field Observations

At a minimum of once per permit term (i.e., one time every five years), each outfall and point of discharge is observed during dry weather (at least 48-72 hours after precipitation) to determine if there are signs of a potential illicit discharge. Dry weather screening will not commence until at least 48 hours after any rainfall event but may commence if less than one tenth of an inch (1/10th inch) of rain occurred during the previous 48 hours.

Trained staff from each collaborative permittee, or their designee, will observe the characteristics of dry weather flow, any staining or residues, and/or water quality at the receiving water body. The minimum data collected from the outfall and point of discharge source screening will include the information listed below:

• Presence/absence of flow
• Deposits/stains on the discharge structure or bank
• Water clarity
• Color
• Odor
• Foam
• Structural condition
• Floatable materials
• Vegetation condition
• Biology (e.g., bacterial sheens, algae, and slimes)
• Trash

Field observation for each outfall or point of discharge source is documented using a field form. The documentation will include observations for each parameter listed above, as well as an identifier for the outfall/point of discharge, weather conditions (time since last rain event), staff conducting the screening, and a photograph.

If an outfall is submerged due to high water, an effort will be made to screen these outfalls during times of the year when the outfall is exposed (e.g., summer months). When the outfall is constantly submerged, dry weather screening will be conducted at the next upstream manhole or catch basin. This alternate location is still representative of the outfall and will be documented on a field form.

Dry weather screening of points of discharge will be conducted at the last manhole or catch basin before a jurisdictional boundary.

Procedure for Performing Field Screening

The following field screening activities will be conducted immediately, but not to exceed one to two days following the initial observations.

Following the identification of dry-weather flow, an upstream investigation will be performed. This investigation will entail reviewing the storm sewer map and tracking or tracing the observed flow upstream to determine the origin. Accessing manholes or catch basins throughout the drainage area until a source is identified may be required.

If the source of the dry-weather flow is not immediately determined, samples of the flow will be collected. In the field, pH will be measured within 15 minutes of collection. The samples will also be analyzed for E. coli, ammonia, and surfactant. For any analysis that cannot be completed in the field, samples will be taken to an appropriate lab by the collaborative permittee or their designee. Additional parameters may be selected based on field observations and potential source of the potential illicit discharge.

If the dry weather flow appears to be groundwater (e.g., clear water with no odor), field screening will occur to verify that the source of flow is uncontaminated groundwater by testing the parameters listed above.

Procedure for Performing Source Investigation

If field screening indicates that additional investigation is necessary to identify the source of the observed dry weather flow, a source investigation will begin immediately, but not to exceed two weeks following the initial observations.

Common methods used as a part of source investigation include, but are not limited to:

• Visual Inspections: Generally visual inspections of sites are conducted as a part of the screening process.
• Records review: Records typically include storm sewer maps, as-built plans, previous dry weather screening, and information regarding land use (residential, commercial, industrial etc.).
• Sound Testing: Sound testing involves tapping or striking a structure and listening for the sound to carry through a pipe. Sound testing is often used to confirm connectivity of the drainage system.
• Dye Testing: Dye testing involves inserting a tracer dye in a plumbing fixture or drainage system and observing the presence of the dye at other locations. Dye testing is often used to confirm connectivity. The use of tracer dyes with the potential to discharge to the surface waters of the state are regulated and require a permit from the Michigan Department of Environment, Great Lakes, and Energy (EGLE).
• Smoke Testing: Smoke testing involves blowing a non-toxic simulated smoke through the collection system to determine connectivity. Smoke testing requires notifying the residents and local authorities. Smoke found exiting a building plumbing vent indicates that the home is illicitly connected to the storm sewer. Smoke testing may be inconclusive when water traps or other blockages are present.
• Video Surveillance: Closed Circuit Television Video (CCTV) sewer inspections are commonly used to look at pipe conditions and locate connecting pipes (or taps) in the sewers. Video the sewer pipes may not by itself confirm connectivity and may be followed by dye testing or other similar approach.
• Sandbagging: Temporarily sandbagging a sewer pipe may be useful to check for intermittent flow conditions. Sandbagging involves partially blocking the lower portion of a drainage pipe and is only used during dry weather conditions.

Non-Stormwater Discharges to a MS4

The following non-stormwater discharges are not authorized in this document, but do not need to be prohibited. Unless the collaborative permittee accepting the discharge identifies them as a significant contributor or source of pollutants entering the MS4, under their jurisdiction these discharges may be allowed to enter the MS4 if approved by the collaborative permittee:

1. a)Water line flushing and discharges from potable water sources
2. b)Landscape irrigation runoff, lawn watering runoff, and irrigation waters
3. c)Diverted stream flows and flows from riparian habitats and wetlands
4. d)Rising groundwaters and springs
5. e)Uncontaminated groundwater infiltration and seepage
6. f)Uncontaminated pumped groundwater, except for groundwater cleanups specifically authorized by NPDES permit
7. g)Foundation drains, water from crawl space pumps, footing drains, and basement sump pumps
8. h)Air conditioning condensates
9. i)Water from non-commercial car washing
10. j)Street wash waters
11. k)Dechlorinated swimming pool and hot tub waters from single, two, or three family residences.
12. l)Discharges or flows from emergency firefighting activities

Procedure for Responding to Illegal Dumping/Spills

Illegal dumping and spills to the MS4 are typically discovered by either visual and/or olfactory observations and are subsequently reported by citizens or staff. An on-going effort to educate the citizens about water quality issues is critical to the success of decreasing illegal dumping into the storm water catch basins/inlets and is included in the Public Education Plan. Citizens are advised to report illegal dumping or spills.

A complaint related to illegal dumping or spills will be investigated by the designated representative of the collaborative permittee receiving the report within 24 hours of receiving notification on business days. If an illicit connection is identified but not immediately resolved, a notification will be transmitted within ten business days to the party responsible of the requirement to eliminate the discharge to the MS4. Responsible parties will be notified within 24 hours on business days if the illicit discharge may endanger health or the environment.

Compliance and Enforcement Procedure for Illicit Discharges, Spills, and Dumping

Large spills requiring emergency response will be handled by Midland Police Department or Midland Fire Department.

When a complaint or report of a suspected improper connection or illicit discharge is received, the following steps will be followed: (1) documenting the complaint or suspicion in the tracking system, (2) investigation, (3) source identification, (4) voluntary and/or enforced corrective action, and (5) administrative tracking of steps 1 through 4 to assure remedy and closure.

Spill Reporting

Emergency response and spill reporting procedures will be developed and incorporated into the facility-specific Standard Operating Procedure (SOP) for each high priority facility identified in the Pollution Prevention and Good Housekeeping section of the stormwater management plan (SWMP).

The noncompliance notification requirements below will be followed in response to all instances of noncompliance, including:

1. 1)Spills, illicit connections, or dumping to the permitted MS4
2. 2)Releases from municipal facilities that result in a discharge to waters of the state

Noncompliance Notification

All instances of noncompliance will be reported as follows:

24-Hour Reporting:

Within 24 hours of becoming aware of any noncompliance which may endanger health or the environment, collaborative permittees, will report to EGLE verbally by calling EGLE’s 24-hour Pollution Emergency Alerting System telephone number, 1-800-292-4706. A written notification will also be included in the required progress report.

Other Reporting:

For other instances of noncompliance, collaborative permittees will provide written notification via MiEnviro Portal as part of the required progress reporting for the permit.

Written notifications will include:

1. 1)A description of the discharge and cause of noncompliance
2. 2)The period of noncompliance, including exact dates and times, or, if not yet corrected, the anticipated time the noncompliance is expected to continue
3. 3)The steps taken to reduce, eliminate and prevent recurrence of the noncomplying discharge

IDEP Training and Evaluation

Training will be provided for all staff employed by collaborative permittees who may come into contact or observe an illicit discharge to the MS4. Training topics will include:

• Techniques for identifying an illicit discharge or connection, including field observation, field screening, and source investigation
• Procedures for reporting, responding to, and eliminating an illicit discharge or connection and the proper enforcement response

Training will occur once every permit term (once every five years) for existing employees and within the first year of hire for new employees.

Evaluation of Overall Effectiveness

At the time each progress report is prepared, staff will compile documentation of illicit discharges and connections discovered during the reporting period, and corresponding method of detection (e.g., dry weather screening, complaint, notification from staff, wet weather screening, or alternate approach), enforcement method used to eliminate illicit discharge, and time elapsed before discharge was eliminated. The most recent method of staff training method prior to the illicit discharge being discovered may also be considered in the evaluation. This information will be reported in the progress report and will be retained to evaluate overall effectiveness at the end of each permit term. The results of the evaluation will be considered when determining IDEP procedures for the next permit term.

IDEP Ordinance(s) or Other Regulatory Mechanism(s)

All IDEP ordinance data is housed by the collaborative permittees per the table below.

Enforcement Venues for County Agencies

The Midland County Road Commission (MCRC) and the Midland County Drain Commissioner (MCDC) do not have ordinance authority; however, the MCDC has limited authority to control water pollution in county drains provided by the state Drain Code of 1956. County Agencies can also use the County’s Public Health Code and obtain enforcement through the Public Health Department to obtain compliance in issues which involve public health and safety as it is related to the Illicit Discharge Elimination program.