This page is a practical explainer, not an official notice or compliance determination. If you have a property-specific letter, follow its instructions and ask your issuing agency when unsure.
Does this requirement apply to your property?
WES states that properties with private stormwater collection and treatment devices must inspect annually, maintain or clean as needed, and submit an annual report. Examples of covered structures can include privately owned storm drains, underground tanks, vaults, oil/water separators, detention facilities, ponds and swales.
The key distinction is WES service area, not simply having a Clackamas County mailing address. Other cities and districts may use different rules. Check your utility, recorded maintenance agreement or WES directly if unsure.
- Confirm jurisdiction: Identify whether WES oversees your property and whether it has private stormwater devices.
- Identify the system: Look for catch basins, manholes, treatment vaults, filters, swales or ponds noted in your site plan.
- Check property-specific instructions: Your notice or operations-and-maintenance plan can add important details.
When is the annual report due?
WES says to send the annual inspection and maintenance report before December 31 each year. For the current 2026 reporting cycle, do not treat December 31 as a guaranteed last-minute submission day—submit early and verify any property-specific instructions in your WES notice.
The deadline is the WES reporting instruction, not a statewide Oregon deadline for all stormwater facilities. If you have received a separate enforcement or corrective-action notice, follow its own timeline rather than assuming the annual report date applies.
- Schedule the inspection with enough time to address findings.
- Record when and by whom the inspection was completed.
- Submit the WES form directly through its official reporting portal before the stated year-end cutoff.
What information does the WES form ask for?
The official online form requests the facility location, owner/contact details, inspector and inspection date, plus the types and numbers of structures inspected, cleaned or repaired.
It includes questions about free-flowing inlet/outlet pipes, vegetation condition, invasive vegetation, sediment accumulation, debris removal, and optional comments. Use the form to report what actually occurred; do not mark work as complete until confirmed.
- Site or facility name and address; contact details.
- Inspector name and inspection date.
- Counts of structures inspected, cleaned and repaired.
- Maintenance or repairs completed and debris removed, when applicable.
How to submit the official report
Use the Clackamas WES Annual Stormwater System Inspection and Cleaning Report. This is the county’s form, not a form hosted by our website. WES also lists a mailing option on its Watershed Protection page.
Keep a copy of the information you submitted and any confirmation for your records. If you do not know what to report, or your notice contains different instructions, contact WES rather than guessing.
- Open the official WES form and complete the actual inspection and maintenance fields.
- Save your confirmation and underlying inspection records.
- Ask WES directly about any uncertainty or property-specific corrective notice.
Do you need a contractor?
A facility may need basic debris removal, vegetated-area work, catch-basin cleaning, or specialist inspection and repairs. WES also describes a Storm Drain Cleaning Assistance Program for eligible basic drain cleaning; program availability and scope should be verified directly with WES.
For vaults, mechanical filters or repairs, ask whether a provider works on your actual system and holds any applicable licenses. A public listing does not establish current qualifications or service coverage.
- Get a written scope identifying which structures will be inspected or serviced.
- Ask for a written record of findings, dates, and completed work for reporting.
- Confirm qualifications and necessary permits before repairs.
Official sources and forms
- WES Watershed Protection: annual requirement, timing and SCAP
- WES official annual stormwater inspection report form
- Clackamas WES forms and documents
Requirements may change. Confirm deadlines, eligibility, maintenance and permit details with the responsible agency for your address.
Need help with the physical work?
Understand the requirements first. Then find publicly listed providers by facility type, and verify service area, current qualifications and insurance before hiring.