Cesspool vs Septic Systems in Hawaii: What Property Buyers Should Know

If you’re buying property on the Big Island of Hawaii, you will likely encounter homes with either cesspools or septic systems.

Understanding the difference is important because Hawaii has been working toward phasing out cesspools statewide.

What Is a Cesspool?

A cesspool is a simple underground pit that collects wastewater from a home.

Unlike modern systems, cesspools do not treat wastewater before it enters the ground.

Many older homes in Hawaii still rely on cesspools because they were the standard wastewater solution for decades.

What Is a Septic System?

A septic system is more advanced.

It includes:

• A septic tank
  
  

• A drain field
  
  

• Wastewater treatment through filtration
  
  

Because septic systems treat wastewater, they are considered much more environmentally friendly.

Hawaii’s Long-Term Cesspool Phase-Out

The State of Hawaii has set a goal to eliminate cesspools by 2050.

This means property owners will eventually need to convert to:

• Septic systems
  
  

• Aerobic treatment units
  
  

• Sewer connections (where available)
  
  

The cost to convert can range from $15,000 to $40,000 or more, depending on site conditions.

Why This Matters When Buying a Home

If a home has a cesspool, buyers should factor in the future conversion cost.

In some cases, lenders may also require inspections or disclosures related to wastewater systems.

Understanding these issues upfront can help buyers plan for future improvements.

Local Knowledge Helps

I often help buyers evaluate properties where wastewater systems may impact financing, insurance, or future costs.

When purchasing property on the Big Island, understanding infrastructure systems like these can make a big difference.