A cesspool is essentially a hole in the ground — often a concrete cylinder with an open bottom or perforated sides. Waste from toilets, sinks and washing machines pours in, percolating out the bottom. This outdated drain-and-drip wastewater system is poised to cause complicated problems in the islands.

There are about 88,000 cesspools in Hawaii — far more than any other state. Collectively, they release about 55 million gallons of untreated sewage into the ground every day, touching off threats such as tainted drinking water (more than 90 percent of our potable water is tapped from groundwater) and coral reef degradation.

The state Department of Health (DOH) recently filed a report with the Legislature pinpointing 14 priority areas where upgrades are needed. Legislators must find ways to effectively accelerate the phasing-out of cesspools — an effort initiated 25 years ago.

In 1992, the state put in place a ban on new cesspools on Kauai and Oahu, most of Maui, Lanai, and portions of Molokai and Hawaii island. Last year, it was applied statewide, ending a practice that had seen 800 new cesspools created every year.

State law currently requires cesspool elimination by 2050. But with the Health Department estimating the price tag at $1.75 billion, or about $20,000 for each fix, environment- and public health-focused aspiration are colliding with economic realities.

Last month, for example, the DOH dropped a program through which it had offered to cover half the cost of installing modern sanitation treatment units on Hanalei Watershed Hui properties when the group’s commitment to 15 upgrades dwindled to four.

Another stalled effort is a $5 million program that offers income tax credits up to $10,000 for upgrading or converting to a septic tank system or an aerobic treatment system, or connecting to a sewer system. However, only cesspools in designated sensitive areas, such as within 500 feet of the ocean, qualify. So, while the program could cover 500 fixes, so far only about 50 taxpayers have used the program.

Both programs should be reworked with more attractive limited-time-offer incentives followed by tough enforcement of deadlines, including fines.

In addition, Hawaii lawmakers should revisit a point-of-sale provision similar to the one prodding progress in Rhode Island, which has the second-largest cesspool tally nationwide. New cesspools were banned there 50 years ago. The phase-out, however, was sluggish until just three years ago, when Rhode Island adopted a provision requiring the scrapping of a cesspool system after sale of a property. Either the buyer or the seller pays for the upgrade, which can become part of the overall sale negotiation.

A similar pitch proposed by Hawaii’s DOH made it to former Gov. Neil Abercrombie’s desk, but it was never signed. Opponents contended that the cost discriminated against low-income residents and expressed doubts about cesspool- related dangers. But evidence confirming dangers is continuing to pile up. Fast. And if paradise is to be maintained, everyone must help foot the bill.

The DOH’s top priority areas are Upcountry Maui and Oahu’s Kahaluu area, where cesspools pose a triple threat: significant risk to human health as well as concerns about drinking water contamination and draining into sensitive waters.

In parts of the aquifer serving Upcountry Maui, there’s elevated groundwater nitrate — beyond concentrations found in natural and agricultural sources. In some areas, well installations would now require expensive treatment to meet drinking water standards, according to the DOH report. Kahaluu, meanwhile, has documented high bacteria counts in the surface water and incidents of skin infections consistent with sewage-contaminated waters.

Hawaii prides itself on stewardship of natural resources. So much so that the state Constitution mandates that we have a “right to a clean and healthful environment.” This pollution problem is overdue for a mitigation vision, with the state and counties backing it up, that will rid the islands of cesspools.