Conducting Visual Assessments - Michigan's New Industrial Storm Water Permit Requirement

by Caitlin Andler
Apr 15, 2015


The Michigan Department of Environmental Quality (MDEQ) Storm Water Program has recently implemented a new requirement for all properties that have a National Pollutant Discharge Elimination System (NPDES) Permit for industrial storm water discharge. The new requirement, a visual assessment, will be added to a facilities permit requirements when their Certificate of Coverage (COC) is renewed. The Industrial Storm Water Certified Operator at the facility conducts this assessment. A facility has six months after their new COC has gone into effect, to update their Storm Water Pollution Prevention Plan (SWPPP) with these new requirements.

"A visual assessment is the observation of storm water discharges from the discharge points at a facility during and/or after a rain event or snow melt" (DEQ, Visual Assessment of Industrial Storm Water Compliance Assistance Document). The sample is collected from the property's storm water discharge during the first 30 minutes of release from a storm event, which occurs at least 72 hours after any previous significant storm event. The sample needs to be collected in a clean, clear container. An Industrial Storm Water Certified Operator must record their observation and take a color photograph of the sample against a white background. It should be noted if there is any turbidity, color, oil films, floating solids, foams, settleable solids, suspended solids, or deposits in the sample. If any of these characteristics are observed, the source of the contamination needs to be determined and corrective action taken to eliminate the contamination source. A visual assessment needs to be made once per quarter, within 30 days of a facility's quarterly inspection.

The goal of the new visual assessment monitoring is to ensure clean storm water discharge. This new testing requirement will help determine if current controls need to be revised to meet the requirement, or as in most cases confirm the controls in place are effective.

Envirologic is available to assist with updating storm water plans, provide storm water discharge management and reporting, or to discuss in detail the new requirements. Please contact our staff for more information or if we can be of assistance.

For added information about the new visual assessment requirements, please review the following documents from the DEQ - Visual Assessments of Industrial Storm Water and Visual Assessment Question & Answer Document. You can find additional information on the DEQ website.

Back to Archived Posts >

Post a Comment

8 + 1 =

Email Alerts

Subscribe to email alerts from the Envirologic Blog.



View Recent Posts


industrial storm water discharge  visual assessment  compliance

Tell Us About Your Project

We'll share our expertise, create a quote and find the best solution for you.

Contact Envirologic
© 2021 envirologic  |  2960 Interstate Pkwy
 |  Kalamazoo, MI 49048
P 800.272.7802  |  F 269.342.4945
This website is Eco-Friendly Small Business Certified Envirologic on Facebook Envirologic on Twitter Envirologic on Linked In