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Welcome to WAI’s Potty Portal:
Technical Assistance for the Cesspool Conversion Process
What is WAI’s Potty Portal?
The Potty Portal is a resource to educate homeowners and those interested about the cesspool issue in Hawaiʻi and the cesspool conversion process.
If you are a cesspool owner and want to get in touch with the WAI team for help with the conversion or a licensed Individual Wastewater System (IWS) installer and would like to be featured on this website, please use the resources below.
Are you a Hawaiʻi homeowner looking to convert a cesspool? Check out these resources!
Do you live on Maui Island? Find out what happens after you flush the toilet on FlushAware!
What is the best individual wastewater system for your property?
IWS ENGINEERS & INSTALLERS
The lists below intend to show every engineer licensed to design Individual Wastewater Systems (IWSs) and every contractor licensed to install IWSs. They are provided for convenience and not to be seen as an endorsement of any specific person or company.
Hawaii Department of Health: List of Individual Wastewater System (IWS) engineers
List of licensed Individual Wastewater System (IWS) installers
If you are an Individual Wastewater System (IWS) installer and would like to be featured on this website, use the button below.
What are cesspools, and why do they need to be converted?
A cesspool is a hole in the ground receiving untreated wastewater. Cesspools pollute the environment and endanger public health.
More info at Hawaii Department of Health: Cesspools in Hawaii
Are all cesspools equally harmful as each other?
Not all cesspools are equally harmful as they can vary in size and the volume of waste they handle. Additionally, the location of the cesspool, the type of waste that is disposed of, and the surrounding soil conditions can also affect the level of harm.
A cesspool that is located near a water source or in an area with high water table could be more harmful than one that is located farther away or in an area with a lower water table.
Graphic by Michael Mezzacapo
The Department of Health’s List of Priority Areas
Where the cesspools are qualified as especially harmful.
What can a cesspool be converted to?
If a cesspool serves the equivalent of five (5) bedrooms or less, it can be converted to an Individual Wastewater System (IWS). More info at What to Expect in Designing your Wastewater Treatment System
While IWSs consisting of a septic tank and a leach field are common, they may not be the best option available depending on your location and conditions. Other more advanced systems can treat waste more effectively and reduce pollution. More info at US Environmental Protection Agency: Types of Septic Systems
A cesspool serving the equivalent of more than five (5) bedrooms is considered a Large-Capacity Cesspool (LCC) with more rules. More info at US Environmental Protection Agency: Large-Capacity Cesspools
What does the Individual Wastewater System (IWS) permitting process look like in Hawaii?
The process involves hiring a licensed civil engineer and a licensed contractor who work with the Hawaii Department of Health. More info at Hawaii Department of Health: Individual Wastewater Systems
Map of Cesspool Locations in Hawaiʻi
Click on the map to see an interactive map based on a number of studies by University of Hawaiʻi and the Department of Health. You can enter any address into the search bar to move the map there. If there is an orange dot at the location you entered, this property is likely served by a cesspool. If the map area is shaded in blue, it is located in one of the cesspool upgrade priority areas as defined by the Hawaiʻi Department of Health. The priority areas will be updated soon. Research is ongoing to better identify properties that are most likely served by cesspools.
Note: Cesspool locations and priority areas are subject to change. Hawaiʻi lacks a complete map of all cesspool locations.
What to Expect When Converting Your Cesspool
The below flowcharts give an overview of the current regulations on Individual Wastewater System (IWS) requirements. Click on each chart to open it in another window. Underlined words link to websites that provide more explanations. There are four flowcharts:
“Regular Property”, use this if you do NOT have multiple systems on your property and are NOT in the No-Pass-Zone on Oahu.
“Multiple Systems”, use this if you have multiple on-site wastewater systems on your property.
“No-Pass-Zone”, use this if you are in the No-Pass-Zone on Oahu.
“Seepage Pit Retrofit”, use this to find out if your existing cesspool can be retrofitted into a seepage pit.
Find a map at this link to check if your property is located in the No-Pass-Zone, which only exists on Oahu. If a location is within the blue area on the map, it is NOT in the No-Pass-Zone.
1: Regular Property
2: Multiple Systems
3: No-Pass-Zone
4: Seepage Pit Retrofit