Water damage restoration, Massapequa, NY

Local conditions

What actually goes wrong in Massapequa

Massapequa floods from the bay side. Its shore faces South Oyster Bay, which the Village of Massapequa Park calls the Great South Bay, and south of Merrick Road the streets run down to canals and bulkheads in neighborhoods like Nassau Shores, Harbor Green and Biltmore Shores. When Sandy’s surge came in on October 29, 2012, most of southern Nassau below Merrick Road went under and the creek-side streets flooded as far north as Sunrise Highway. It does not take a hurricane: a nor’easter in January 2017 put one to two feet of water in Nassau Shores.

• Tidal and storm-surge flooding of canal-front homes south of Merrick Road
• Bay water backing up through the storm drains at high tide
• Category three water in anything that crossed the ground or a bulkhead
• Flooded basements, crawlspaces and the enclosures under raised houses

Canal houses, 1950s blocks and flooded basements

Half of Massapequa’s houses were built in the 1950s and 97 percent are detached, according to the Census Bureau’s 2020–24 estimates. Post-war demand replaced the old estates with developments like Harbor Green, Biltmore Estates and Nassau Shores. Harbour Green’s first 113 houses went up between 1932 and 1941, two stories with basements, and after the war the land toward Dartmouth Road was filled and the Gloucester Canal dug out.

The Sandy flood-insurance claims show what that housing looks like from underneath. Of the 2,711 claims in the 11758 ZIP, 968 recorded a basement or enclosure, finished or not, and 370 a below-grade crawlspace. Houses lifted since then have a new space to look after: the enclosure under the raised floor, which is built to let floodwater in and out and has to be finished with that in mind.

South Oyster Bay, storm surge and the canals

Massapequa Creek runs south through the Massapequa Preserve, 423 acres of former New York City watershed land that begins at Merrick Road, past Massapequa Lake and the reservoir and out into the bay through Massapequa Cove. The ordinary tidal range in South Oyster Bay is only about a foot and a half; it is wind-driven tidal surges on top of it that bring the bay into the streets.

Groundwater is not the story here the way it is in Smithtown. Sewering drew the water table down across most of Nassau, as Suffolk County’s own hazard plan notes of the island’s built-up areas. The water intrusion that damages Massapequa houses arrives over the bulkhead, up through the storm drains or out of the sky.

Storm drains that run backwards

About 85 percent of Nassau is on public sewer, with the remaining cesspools concentrated on the North Shore, and the Massapequa Water District’s own history records Nassau County laying sewers through its growth years. The drainage problem here is the other set of pipes.

South Shore storm drains empty into the canals and the bay, so when the tide is high enough the bay comes back up through them and a street floods with no rain at all. After Sandy the Town of Oyster Bay spent upwards of $12 million of federal grant money on the low-lying streets of the Massapequas, among them Harbor Place, Brockmeyer Drive, Clearwater Avenue and Iroquois Place to Unqua Circle: bigger drainage pipe at a better pitch, underground retention, tidal check valves and, in places, a higher road. The work was finished in January 2024.

Water that came in from the street or over the bulkhead is category three, whatever it looks like. Porous materials it reached come out and everything left is decontaminated before drying. Bay water also leaves salt behind in the framing, which keeps pulling moisture back in until it is washed out.

Flood damage on record in Massapequa

1. October 29, 2012 (Sandy)

   A surge of about eight to nine feet on a normal high tide put three to five feet of water into southern Nassau. The National Weather Service recorded most of it below Merrick Road as completely inundated, creek-side streets flooded up to Sunrise Highway, and major residential damage in Massapequa. FEMA’s records hold 2,711 flood-insurance claims from Sandy in the 11758 ZIP code alone.

2. August 28, 2011 (Irene)

   The storm before Sandy: 691 flood-insurance claims from the 11758 ZIP code.

3. January 24, 2017

   A nor’easter, not a hurricane, put one to two feet of water on Delta Road and in Nassau Shores, according to the National Weather Service.

4. January 25, 2024

   The Town of Oyster Bay finished its drainage and tidal check-valve project on the low-lying streets of the Massapequas.

Mold · by appointment

Mold removal in Massapequa

After a tidal flood, mold is a question of what was left in the walls. Houses that were gutted and rebuilt after Sandy are generally sound. The trouble is the ones where wet insulation, a bottom plate or a subfloor was dried in place without being cleaned, and the growth comes back every humid summer.

In a raised house, check the enclosure underneath and anything stored in it. It is built to let floodwater in and out, and whatever sat in it through a tide should be treated as having been in category three water.

Mold remediation is booked, not dispatched

Mold remediation is scheduled work. Nobody needs a crew at two in the morning for mold growth that took weeks to appear, and a contractor who sells it as an emergency is selling the fear rather than the fix. The job starts with a survey: where the hidden moisture is coming from, how far the growth goes behind the finish, and whether the area is large enough to fall under New York’s mold rules. Mold prevention after a water loss is mostly moisture control: dry the structure to its standard, then keep indoor humidity between 40 and 60 percent.

Once a project covers more than about ten square feet, Article 32 of the New York Labor Law separates the person who assesses the mold from the company that removes it, and the same firm may not do both on one job. That is why the clearance test at the end goes to an independent assessor, not to us. How mold inspection works on Long Island sets out the whole rule.