Two construction eras share one place name
The 2020 to 2024 American Community Survey counts 13,565 housing units here at a median year built of 1955, plus or minus two (B25035). The bands are not one story. There are 7,840 plus or minus 514 units from the 1950s and 1,048 plus or minus 327 from the 1960s, but also 2,081 plus or minus 393 from the 1940s and 1,138 plus or minus 301 built in 1939 or earlier, with 209 plus or minus 94 from the 1970s (B25034).
Those two groups are different buildings behind similar listings. Pre-war framing, foundations and wiring carry their own recurring items; a tract house built to a repeated plan and extended since carries another set. The build year on the property record separates them.
Structure type is mostly but not entirely houses: 12,668 of the 13,565 units are single-unit detached, with 283 in two-unit buildings, 316 in buildings of three or four units, 151 in buildings of ten to nineteen and 57 in buildings of fifty or more (B25024). Of 13,356 occupied units, 11,422 are owner-occupied and 1,934 are rented (B25003).
Heating fuel splits close to the middle
Utility gas heats 6,676 occupied units and fuel oil or kerosene heats 5,297, with 811 on electricity and 361 on bottled or LP gas (B25040). A split like that in a stock of this age means conversions have happened at scale, and a converted house is where an unused oil tank is most easily forgotten.
Nassau does not defer to the state on tanks. The environmental agency's rule summary names four counties, Nassau among them, that "administer their own PBS programs for their respective localities" (petroleum tank regulations), so whatever file exists for a tank at a Nassau address is a county file rather than a state one. Some of it is visible without tools: the two short pipes that once took a delivery hose, a feed line that stops at a blank wall, ground that has slumped along a driveway edge. The removal record is the document to ask a seller for. Questions, not statements about this community.
Permits, and the difference between a postmark and a jurisdiction
The Census Bureau carries Hicksville as a census designated place, GEOID 3634374, whose polygon lies within Oyster Bay town on the county subdivision layer (TIGERweb place and county subdivision layers). The Town of Oyster Bay Building Division states that applications "can be obtained at the Building Division located at 74 Audrey Ave in Oyster Bay as well as the Building Division Annex located in Town Hall South (977 Hicksville Rd in Massapequa)," and the same division issues certificates of occupancy. The listed number is (516) 624-6200, extension 1.
A census designated place is a statistical outline, not a municipal line, and postal delivery follows neither. An envelope addressed to Hicksville can reach a property outside it, and a Nassau village keeps its own permit file. Settle the municipality for the parcel in the county's Land Records Viewer first; the wrong office returns an empty search rather than a clean one.
Water is a district of its own
The state health department lists Hicksville Water District as a community water system, PWS identifier NY2902829, population served 48,000, at 4 Dean Street, Hicksville, NY 11801 (Nassau public drinking water contacts). That address is a district office rather than a boundary description, so it evidences the ZIP at that location and nothing about coverage across the place.
The rail entry, as the state codes it
The state's rail station dataset carries a Long Island Rail Road station named Hicksville, code HVL, branch coded Port Jefferson, fare zone 7, accessibility entered as FULL (MTA rail stations). Those are the dataset's field values; the accessibility entry is administrative, not a survey of any platform.
Sewer status, and how much weight it carries
On the county's list of sewer authorities by community, the entry beside Hicksville names the Nassau County Department of Public Works, and no asterisk sits with it — the document reserves that mark for communities running collection themselves. Nor does the name appear in the document's other roll, the communities it groups as not publicly sewered, which runs to 34 entries. Neither point reaches a single parcel: a house on a sewered street can still have an abandoned cesspool nobody ever tied in. The list shows no date of its own and arrives without a last-modified header or entity tag, so how current it is cannot be said. The Land Records Viewer is where an address-level answer starts.
Flood mapping belongs to the town record
Flood participation is recorded for the town, not the hamlet. Oyster Bay appears as NFIP community 360483, first rate map August 1, 1978, current effective map date September 11, 2009, participating, no sanction, and with no rating entered under the Community Rating System (the NFIP community status book for New York). That last blank has a price attached: nothing discounts a premium written here. And a town entry describes no lot. Zones are drawn panel by panel, Zone X takes in the 500-year floodplain as well as ground beyond it, and the panel for an address is at FEMA's Map Service Center.
Put the questions to the seller in writing
New York hands the buyer a lever here. A seller of a house with one to four dwelling units must deliver form DOS-1614-f, the Property Condition Disclosure Statement, revision 06/23, before signatures bind (Department of State). With a pre-1940 count above a thousand units here, question 3's note comes first: "If the structure was built before 1978 you are encouraged to investigate for the presence of lead based paint." Question 14 covers fuel storage tanks above or below ground and whether any has leaked; question 28 makes the seller tick public sewer, private sewer, septic or cesspool; and question 31 asks the seller outright, "Does the basement have seepage that results in standing water?"