Oakland County Septic Inspection Guide: Time of Sale Requirements

If you're buying or selling a home with a septic system in Oakland County, Michigan, you'll need to understand the Time of Sale inspection requirements. This comprehensive guide covers everything you need to know about the process, what inspectors look for, and how to ensure your system passes.

What Triggers an Oakland County Septic Inspection?

In Oakland County, Michigan, a septic system inspection is required when a property with an on-site sewage disposal system (septic system) is being sold. This is known as a "Time of Sale" inspection and is a mandatory part of the real estate transaction process.

The inspection requirement applies to all residential septic systems that serve single-family homes in Oakland County. Commercial properties and multi-unit buildings may have different requirements—check with your local health department for specifics.

Michigan DEQ and Oakland County Regulations

Septic system inspections in Oakland County fall under Michigan Department of Environment, Great Lakes and Energy (EGLE) regulations, which replaced the former DEQ. These inspections ensure that on-site sewage disposal systems meet current state and local standards.

Key regulatory points:

• Inspections must be performed by a certified septic system inspector
• The inspection follows Michigan's on-site sewage disposal system rules
• Oakland County Health Department oversees compliance in the county
• Sellers are responsible for providing inspection results, though either party can commission the inspection
• If the system fails, repairs must meet current EGLE standards before closing

What Does a Time of Sale Inspection Include?

Visual Inspection of the Tank

The inspector will locate your septic tank, open the access cover, and visually inspect the interior. They'll look for:

• Tank structural integrity (cracks, corrosion, deterioration)
• Liquid level and the presence of scum and sludge layers
• Baffles (dividers inside the tank that direct flow)
• Signs of leakage or seepage

Drain Field Assessment

The inspector evaluates the drain field (absorption field) to ensure it's functioning properly:

• Visual inspection for standing water or wet spots over the drain field area
• Observation of grass color and growth patterns (unusually green areas indicate problems)
• Checking soil composition and drainage characteristics
• Assessing separation distance from wells, property lines, and surface water

Soil Percolation Testing (If Required)

In some cases, especially if the drain field appears compromised or the property is being modified, the inspector may recommend or require a perc test. This test measures how quickly soil absorbs water and determines if the soil is suitable for septic system use. Perc tests can add $300–$800 to the inspection cost.

System Accessibility and Safety

Inspectors verify that:

• The tank is properly marked and accessible
• No structures or vehicles are parked over the tank or drain field
• The system meets setback requirements from wells and surface water

Plumbing System Function

The inspector may review whether the home's plumbing system drains properly into the septic system. They'll check for evidence of backups, slow drains, or other issues.

Pass/Fail Criteria: What Inspectors Look For

An Oakland County septic inspection results in one of three outcomes: Pass, Conditional Pass, or Fail.

Systems That Pass

Your system passes if:

• The tank is structurally sound with no major cracks or leaks
• The tank contains appropriate levels of sludge and scum (not overfull)
• The drain field is not saturated or failing
• No standing water or odors are present around the tank or drain field
• Proper setback distances are maintained
• The system meets current EGLE standards

Conditional Pass

A conditional pass means the system is currently functional but may have minor issues that don't prevent immediate use. Common conditions include:

• Tank needs cleaning/pumping
• Minor tank repairs needed
• Drain field cover needs restoration
• System approaching capacity for household size

Conditional passes typically require corrective action within a specified timeframe—often 30–90 days after closing.

Failed Inspections

A system fails if it poses a public health or environmental risk. Common failure reasons:

• Tank is cracked, collapsed, or severely deteriorated
• Drain field is failing (standing water, sewage surfacing)
• System is contaminating groundwater or a well
• System is inadequate for the home's current or intended use
• System doesn't meet current setback or design standards

If a system fails, it must be repaired or replaced before the property can close—or the buyer must be aware and accept the non-functional system. Repairs can cost anywhere from $2,000 (minor repairs) to $20,000+ (full system replacement).

What Happens If Your Septic System Fails?

If your system fails inspection, you have several options:

1. Make Repairs

For many failures, repairs can restore the system to passing status. Common repairs include tank cleaning, pumping, baffle replacement, or drain field remediation. Work with a licensed septic contractor to address the specific issues found.

2. Replace the System

If the tank is beyond repair or the drain field has failed, replacement may be necessary. Michigan requires new systems to meet current EGLE standards, which can include:

• Larger tank size than original
• Advanced treatment units (if soil or water conditions warrant)
• Proper separation distances from wells and water bodies

3. Negotiate with the Buyer

In some cases, sellers and buyers negotiate a price reduction to account for necessary repairs. The buyer assumes responsibility for fixing the system after closing. This requires buyer awareness and acceptance in writing.

4. Obtain a Variance or Waiver

In rare cases, the Oakland County Health Department may grant a variance allowing non-compliant systems to remain in place. This is uncommon and typically only for systems that pose minimal risk.

Costs and Timeline

Inspection Costs

A standard Time of Sale septic inspection in Oakland County typically costs $400–$800, depending on:

• System accessibility and tank location
• Whether perc testing is needed
• Inspector's experience and local rates
• Any additional testing or evaluation

Timeline

Septic inspections are typically completed within 3–7 business days of scheduling. However, the overall timeline depends on:

• Inspector availability
• Weather conditions (heavy rain can affect testing)
• Whether additional testing is required
• Time needed to address any issues found

It's wise to schedule inspections early in the real estate process to allow time for repairs if needed.

How to Prepare Your System for Inspection

Michigan-Specific Considerations

Michigan's climate and soil conditions can affect septic system performance:

Frozen Ground

Michigan winters can freeze the ground, affecting drain field function. Inspectors understand this and may schedule inspections during warmer months when the system is functioning normally.

High Water Table

Parts of Oakland County have high groundwater levels, which can compromise drain fields. Systems in these areas may require special designs or more frequent pumping.

Soil Type

Michigan soils vary widely. Clay-heavy soils drain poorly and require larger drain fields. Sandy soils drain too quickly and may not provide adequate treatment. Inspectors assess soil type and recommend appropriate system designs.

Common Questions About Oakland County Septic Inspections

Can a septic system pass if it hasn't been pumped recently?

It's possible but not guaranteed. A full tank may fail inspection because the inspector can't see the tank interior properly. Pumping before inspection increases the likelihood of passing.

Who pays for the inspection?

The seller typically initiates the inspection, though either party can commission one. Inspection costs are usually negotiated as part of the real estate transaction.

How often should a septic system be pumped?

Every 3–5 years for a typical family of four. Systems with more occupants or higher water usage may need more frequent pumping. Learn more about pumping frequency.

What if I'm buying a home and the inspection shows a problem?

You have the right to request repairs, a price reduction, or repair escrow (funds held until repairs are completed). Don't proceed with a failed system without addressing the issue.

Get Your Septic System Inspected Today

If you're buying, selling, or just want peace of mind about your system's status, Holly Septic Services can help. We're experienced with Oakland County's inspection requirements and can provide reliable assessment and repair recommendations.