US Bridges

Floyd Pkwy Ext over Narrow Bay

PoorPosted for load

Suffolk County, New York · SW of Mastic Beach · Structure no. 000000003300770

Built
1959
66 years old
Condition
Poor
inspected October 2024
Type
Movable - Bascule
Steel
Length
1,220 ft
3 main spans
Daily traffic
4,381
2020 count
Owner
County
County Highway Agency

About this bridge

Floyd Pkwy Ext over Narrow Bay is a steel movable - bascule carrying Floyd Pkwy Ext over Narrow Bay in Suffolk County, New York. It was built in 1959, so it is 66 years old, older than the New York average of 53 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: posted for load restriction.

It carries about 4,381 vehicles a day, roughly 3% of them trucks, projected to reach 5,054 by 2041. The structure is 1,220 ft (371.9 m) long and 36 ft wide.

CarriesFloyd Pkwy Ext
CrossesNarrow Bay
LocationSW of Mastic Beach
RouteCounty Highway 0
Coordinates40.73705, -72.86751
Functional classUrban Other Principal Arterial

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating40 US tons
Inventory rating24 US tons

Structure

Structure typeMovable - Bascule
MaterialSteel
DeckConcrete, cast-in-place
Main spans3 (+16 approach)
Design loadHS 20
Structure length1,220 ft (371.9 m)
Longest span90 ft (27.4 m)
Deck width36 ft (11 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,381 (2020)
Projected traffic5,054 by 2041
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed—
TollToll bridge
National Highway SystemYes

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedWidening with deck rehabilitation or replacement
Estimated improvement cost$71.2 million (2024 estimate)
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was Floyd Pkwy Ext over Narrow Bay built?

It was built in 1959, making it 66 years old in 2025.

What condition is Floyd Pkwy Ext over Narrow Bay in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in October 2024.

How much traffic does Floyd Pkwy Ext over Narrow Bay carry?

About 4,381 vehicles per day (2020 count), of which roughly 3% are trucks.

How long is Floyd Pkwy Ext over Narrow Bay?

The structure is 1,220 ft (371.9 m) long with a longest span of 90 ft (27.4 m) and a deck 36 ft wide.

Who owns Floyd Pkwy Ext over Narrow Bay?

It is owned by the County Highway Agency.