Three new studies confirm what Elizabeth Boineau knows first-hand: Coastal flooding is getting worse, and in some cases is driving down property values. Her two-story colonial at 128 Beaufain St., worth close to $1 million a few years ago, is now a tear-down after repeated flooding. The lot will soon go on the market for $599,000.

According to a first-of-its-kind study by the Brooklyn-based First Street Foundation, Charleston-area homes collectively declined in value by $266 million between 2005 and 2017 due to damage from tidal flooding. Depreciation by 2033 is pegged at $653 million based on estimates by the Army Corps of Engineers that sea levels will have risen 6 inches by then.

That may seem counterintuitive in a region where home values have mostly skyrocketed, especially compared to a relatively anemic increase in area median wages. But other data seem to confirm the findings.

A third study done at Harvard University found that homes at higher elevations were appreciating faster than those in lower, flood-prone areas, something researchers called “climate gentrification.”

The specific findings varied, but the takeaway is clear. Charleston is in for a watery future, and declining property values could hurt homeowners financially and shrink the tax base, leaving the city in a weakened position to raise money for fixes.

The First Street Foundation study, based on tidal flooding rather than hurricane surges, looked at 5.5 million residential real estate transactions in Florida, Georgia, South Carolina, North Carolina and Virginia.

Statewide, more than 92,000 South Carolina properties have already lost value because of damage from tidal flooding, the study found.

Among cities, Charleston ranked No. 3 in assessed-value declines behind Miami and Hollywood, Florida. In Charleston, the study found 5,543 residential properties already at risk of depreciating due to tidal flooding, with that number rising to 8,349 over the next 15 years. An interactive flood map of the area, developed as part of the study, is available at floodiq.com.

Hospitals, fire and police stations and other public safety infrastructure also are at risk. By 2033, two police stations, three fire stations, 17 schools, six medical facilities and 52 religious sites in the Lowcountry will be at risk, according to the study.

The near-term cost of flood-proofing Charleston has been estimated at $2 billion — just to fix problems within city limits. That’s an already staggering total that would be harder to raise if the tax base were to take a hit.

The scenario isn’t a pretty one, but it should grab the attention of lawmakers in Columbia who balked this year at a bill that would have enabled the city to use a cut of its tourism taxes to fund flood-relief projects. We need all the money we can get.

And local officials must coordinate rules on new developments to ensure that homes are built to withstand not just current conditions, but a wetter future as well.

Charleston will have to come up with a number of creative solutions to address tidal flooding, and it is clear the city also will need state and federal help. The only thing we cannot do, as the studies suggest, is wait.