US Bridges

Maple Ave over Black Brook

Poor

Cheshire County, New Hampshire · Downtown Keene · Structure no. 013600900010100

Built
1961
64 years old
Condition
Poor
inspected November 2024
Type
Culvert
Steel
Length
23 ft
3 main spans
Daily traffic
3,502
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Maple Ave over Black Brook is a steel culvert carrying Maple Ave over Black Brook in Cheshire County, New Hampshire. It was built in 1961, so it is 64 years old, older than the New Hampshire average of 56.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 3 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.

It carries about 3,502 vehicles a day, roughly 3% of them trucks, projected to reach 5,182 by 2043. The structure is 23 ft (7 m) long. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesMaple Ave
CrossesBlack Brook
LocationDowntown Keene
RouteCity Street 0
CountyCheshire County
StateNew Hampshire
Coordinates42.94993, -72.32313
Functional classUrban Collector

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
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert3 SeriousLoss of section, deterioration, spalling or scour have seriously affected primary structural components.
Last inspectionNovember 2024
Inspection intervalevery 16 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating99 US tons
Inventory rating99 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans3
Design loadUnknown
Structure length23 ft (7 m)
Longest span6 ft (1.8 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,502 (2023)
Projected traffic5,182 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusPossibly eligible for the National Register; requires further investigation
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$314,000 (2025 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Maple Ave over Black Brook built?

It was built in 1961, making it 64 years old in 2025.

What condition is Maple Ave over Black Brook 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 November 2024.

How much traffic does Maple Ave over Black Brook carry?

About 3,502 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Maple Ave over Black Brook?

The structure is 23 ft (7 m) long with a longest span of 6 ft (1.8 m).

Who owns Maple Ave over Black Brook?

It is owned by the City or Municipal Highway Agency.