What Fails a Stormwater Inspection? 6 Common Red Flags

If your stormwater facility recently failed an inspection – or you’re worried it might – you’re not alone. From commercial centers to HOAs to industrial properties, stormwater infrastructure failure is more common than many property owners realize. The key is knowing what triggers a failed inspection, and more importantly, what steps to take next to restore compliance and avoid costly penalties.

In this guide, we’ll walk you through the top red flags inspectors look for, and how to respond effectively if your system doesn’t pass.

🚩 Top Reasons Stormwater Systems Fail Inspections

Whether you’re in Maryland, Virginia, DC, or Delaware, most stormwater inspection criteria follow similar standards – especially in MS4 jurisdictions and under NPDES permitting programs. Here are the most common red flags that can lead to a failed stormwater inspection:

1. Sediment Buildup in Inlets or Ponds

Over time, sediment accumulates in stormwater inlets, forebays, and ponds – reducing their storage capacity and flow control. If buildup exceeds allowable limits, the system can no longer function properly, especially during storms.

✅ Tip: Regular sediment removal is more cost-effective than waiting for a full dredging.

2. Clogged or Damaged Outlets and Pipes

When water can’t exit the system efficiently, flooding and erosion become immediate risks. Inspectors often flag broken risers, crushed pipes, or outlet obstructions from debris or vegetation.

✅ Tip: Jet-cleaning pipes and conducting internal CCTV inspections can help identify hidden blockages.

3. Erosion or Bank Instability

Erosion around pond edges, swales, or channels not only weakens structural integrity – it introduces excess sediment into receiving waters, violating water quality standards.

✅ Tip: Stabilize slopes with proper vegetation or riprap and fix undercutting early.

4. Invasive or Overgrown Vegetation

Plants like phragmites or cattails can choke out intended vegetation in BMPs (best management practices) like bioretention areas or wetlands. Excess growth also limits access for maintenance and disrupts water flow.

✅ Tip: Routine mowing and selective removal helps maintain hydraulic function and visibility.

5. Standing Water or Mosquito Breeding Conditions

Except in retention facilities, standing water often signals drainage issues. Mosquito breeding complaints can trigger public health concerns and enforcement notices.

✅ Tip: Remove obstructions, improve infiltration, and repair grading to encourage proper flow.

6. Missing or Incomplete Inspection Records

Many jurisdictions require annual inspection documentation – and failure to provide these records during an audit can itself be a compliance violation, regardless of system condition.

✅ Tip: Maintain a digital log of all inspections, maintenance tasks, and repairs.

🚨 Failed Your Stormwater Inspection? Here’s What to Do Next

A failed inspection doesn’t have to spell disaster. If you take swift, informed action, you can mitigate the issue and regain compliance.

1. Review the Inspection Report Thoroughly

Most inspection reports will include a list of deficiencies with photos, explanations, and required timelines for corrective action. Review this with your stormwater contractor or engineer to determine next steps.

2. Prioritize Repairs by Risk and Timeline

Address high-risk issues – like blockages, structural damage, or erosion – first. Some jurisdictions may allow extensions for non-critical repairs, but others enforce tight timelines.

3. Document All Repairs and Maintenance

Keep a record of all remedial work done. Take before-and-after photos and retain invoices. This can help you avoid future violations and demonstrate compliance if you’re ever audited.

4. Schedule a Re-Inspection (If Required)

Some municipalities require a follow-up inspection to close out a failed report. Others may accept documentation from a certified inspector or maintenance provider.

5. Implement a Long-Term Maintenance Plan

Many failures stem from neglect, not major malfunctions. Partnering with a qualified stormwater maintenance provider ensures regular inspections, cleanouts, and vegetation management to prevent future issues.

⚠️ What If You Receive a Notice of Violation (NOV)?

In some cases, a failed inspection can escalate into a Notice of Violation (NOV) from your local or state regulatory agency. An NOV is an official warning that your property is out of compliance with stormwater regulations and may face enforcement action if issues aren’t corrected within a specified timeframe.

Receiving an NOV doesn’t necessarily mean fines are inevitable – but it does mean the clock is ticking. Ignoring it can lead to escalating penalties, liens, or even legal action.

✅ Act quickly by addressing the violations, documenting corrective actions, and working with a certified stormwater professional to ensure full compliance. The faster you respond, the more likely regulators are to be cooperative.

🛠️ Proactive Maintenance Prevents Future Failures

The best way to avoid failed inspections is to take a proactive approach to stormwater maintenance. That means:

• Annual (or more frequent) inspections by a certified provider
• Routine sediment removal and vegetation control
• Prompt repairs when issues are identified
• Comprehensive documentation

Not sure what your system needs? Our team can help assess your facility and create a maintenance plan that fits your property and jurisdictional requirements.

📍 Serving Maryland, Virginia, DC, and Delaware

iSTORMWATER helps property owners, managers, engineers, and HOAs stay compliant with local stormwater regulations. Whether your facility failed an inspection, you received a NOV or you want to get ahead of future issues, we’re here to help.

Contact us today at (410) 231-3455 for a professional inspection or maintenance quote.