Why a place name is the wrong unit for a flood answer
Queried against Seaford's census outline, FEMA's National Flood Hazard Layer returns Zone AE, Zone X shaded at the 0.2-percent annual chance and Zone X unshaded, all under countywide identifier 36059C. Understand what that outline is before reading anything into which zones came back: a line drawn to tabulate statistics, not the extent of the place as the name is used. The geography behind it is 2.61 square miles of land to 0.06 of water, 2.1 percent of the whole (TIGERweb geography).
So the result the layer gave — AE and shaded X inside that boundary, with no VE polygon falling inside it — is a fact about a query, and shortened to “Seaford has no V zone” it becomes both false and dangerous. An envelope address is not a census geography; the two lines serve different purposes and need not agree. Coastal high hazard mapping takes no notice of a tabulation boundary. Pull the panel for the parcel itself at FEMA's Map Service Center. The NY Rising Seaford/Wantagh plan covers two hamlets as a single planning area, and nothing numeric is taken from it for this page.
Shaded X earns its own warning: mapped here, outside the mandatory purchase area, and still mapped as flood-prone. It is where a purchaser hears “not in a flood zone,” declines coverage, and later meets a lender reading it otherwise.
A hamlet, with the file at the town
Seaford is recorded as a census designated place under status code 57, and its town subdivision is Hempstead, 3605934000; the Town of Oyster Bay lies to its east. There is no village government, so the Town of Hempstead Building Department issues permits and keeps the certificate of occupancy record, and an open permit shows through the town permit portal. A rebuild or a substantial improvement would have engaged the town's flood damage prevention rules and left paperwork a purchaser can ask to see.
The Babylon Branch stops here: station code SFD, fare zone 7, accessibility recorded as FULL in the state's rail stations dataset. That value is the state's own, and holding it is not the same as having walked the platform.
The stock, band by band
There are 5,389 housing units, median year built 1958 with a two-year margin (median year built). The distribution behind it (year structure built):
- 2,423 units from the 1950s and 880 from the 1960s;
- 598 finished before 1940, and 263 during the 1940s;
- 589 from the 1970s, 80 from the 1980s, 98 from the 1990s;
- 218 from the 2000s and 226 from the 2010s.
A house completed after 2000 in an otherwise post-war hamlet is likelier a replacement or heavy reconstruction than infill on vacant ground. Structure type barely varies — 5,041 of the 5,389 are detached single-unit houses, 119 sit in two-unit buildings and 67 are attached (units in structure) — and 4,858 of 5,227 occupied units are owner-occupied (tenure).
A third of occupied homes burn oil
Fuel oil or kerosene heats 1,771 of 5,227 occupied units, close to a third, with 3,312 on utility gas, 87 on electricity and 38 on solar (house heating fuel). At that share, basement and buried tanks are both in ordinary circulation, and what settles a removed tank is the abandonment record — better requested before closing than discovered after. A September 2026 query of the state's spill incidents file returned upwards of 890 records against this locality name, more than 800 petroleum, private dwelling ahead of the other source categories. Each row is a filing entered under a typed place name. The total counts filings, not addresses, and a larger one reflects more reporting rather than more hazard.
Supply, and what the service line filings show
All of the county's drinking water is groundwater drawn from beneath Long Island. The county counts 46 public water systems and describes those as tested for over 150 different contaminants. Its roughly 500 private wells are a count on the same page, with no testing attached (county public water supply). The state's Nassau public water system roster holds none named for this hamlet, so the supplier has to be pinned down address by address. The service line filings are grouped by a typed place name, which appears here in two casings: 7,245 non-lead, one galvanized requiring replacement and eight unknown in one, 138 non-lead in the other, with nothing at all in the lead category. Ask the same file for ZIP 11783 and 7,392 rows come back. Nowhere in it is a water utility named. That is the inventory as submitted, not a promise about one line, and it covers nothing inside the house.
Collection district: county authority, parcel unknown
Look Seaford up on the county health department's roster of public sewer collection districts and the entry beside it reads Nassau County Department of Public Works, with nothing flagging a community that handles collection itself. The same sheet marks other Nassau communities as not publicly sewered, so the column is a genuine binary rather than a roster of where the county happens to operate.
Both caveats have to travel with that. No date appears anywhere on the sheet and the file arrives with no last-modified header, so a reader cannot date it. And it assigns an authority to a community rather than certifying that a given house is tied into a main — which is why the county describes cesspools and septic systems as “a cost-effective and environmentally sound alternative to sewers in areas that are outside designated sewer areas” (Nassau Septic) and funds replacements at up to $20,000 apiece. Its conditions run the other way from this page, though. A qualifying property must not be “located within an existing or proposed sewer district,” and the single opening is a site constraint the district itself puts in writing. Only the county's Land Records Viewer answers the question for one property.