With 88,000 cesspools — far more than any other state — Hawaii is king of the underground hole used for disposing of human waste.
But the state is moving to end the practice, and a state Department of Health report released Tuesday identifies 14 areas where officials say interim cesspool upgrades are critically needed to protect public health and the environment.
The priority areas account for about half of the state’s cesspools and, according to the report, represent either a significant risk to human health or a threat to drinking water or could drain into sensitive waters.
The highest priority was assigned to upcountry Maui and Kahaluu, where cesspools are a threat in all three categories.
“The report findings are troubling and show wastewater from cesspools is beginning to impact drinking water in some parts of upcountry Maui,” Health Director Dr. Virginia Pressler said in a news release.
Pressler added that water in the identified areas is still safe to drink, with no evidence of bacterial contamination.
“However, there are early warning signs that tell us we must act now to protect the future of our drinking water and the environment,” she said.
The department presented its cesspool report to state lawmakers and will hold community meetings in priority areas across the state in January, beginning with Makawao on Jan. 9 and Kahaluu on Jan. 12.
Cesspools allow raw, untreated sewage to be emptied directly into the ground, where it can contaminate ocean water, streams and groundwater with disease-causing pathogens and nitrates.
Officials have estimated that cesspools discharge about 53 million gallons of raw sewage into Hawaii’s groundwater every day.
Meanwhile, more than 90 percent of Hawaii’s drinking water comes from groundwater, officials said.
Tuesday’s report was ordered by Act 125 of the state Legislature earlier this year.
Last year Gov. David Ige signed wastewater system rules that banned all new cesspools statewide, ending a practice that saw 800 new cesspools being created in the islands every year.
State law currently requires the elimination of cesspools by 2050. The Health Department has estimated the cost of upgrading all of the state’s 88,000 or so cesspools at $1.75 billion, or about $20,000 for each one.
Last year’s wastewater system rules offered temporary income tax credits under Act 120 for the cost of upgrading or converting a qualified cesspool to a septic tank system or an aerobic treatment system, or connecting to a sewer system.
Taxpayers may apply for a tax credit of up to $10,000 for cesspools upgraded to a sewer or septic system over the next five years, but the program is limited to a total of $5 million, or about 500 cesspools a year.
According to the law, owners of cesspools situated within 500 feet of the ocean, streams or marshes, or near drinking water sources, can qualify for the tax credit. So far only about 50 taxpayers have used the program, officials said.