US Bridges

Old Mamalahoa HWY over Kaula Gulch

PoorPosted for load

Hawaii County, Hawaii · Tmk 4-1-01:15 · Structure no. 001410001100001

Built
1928
97 years old, rebuilt 2009
Condition
Poor
inspected June 2023
Type
Girder and Floorbeam System
Steel
Length
52 ft
3 main spans
Daily traffic
300
1986 count
Owner
County
County Highway Agency

About this bridge

Old Mamalahoa HWY over Kaula Gulch is a steel girder and floorbeam system carrying Old Mamalahoa HWY over Kaula Gulch in Hawaii County, Hawaii. It was built in 1928 and reconstructed in 2009, so it is 97 years old, older than the Hawaii average of 63.8 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 300 vehicles a day, projected to reach 360 by 2030. The structure is 52 ft (15.9 m) long and 16 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesOld Mamalahoa HWY
CrossesKaula Gulch
LocationTmk 4-1-01:15
RouteCounty Highway 0
StateHawaii
Coordinates20.00947, -155.28601
Functional classRural Local

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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating21.4 US tons
Inventory rating16.8 US tons

Structure

MaterialSteel
DeckWood or timber
Main spans3
Design loadUnknown
Structure length52 ft (15.9 m)
Longest span17 ft (5.2 m)
Deck width16 ft (4.9 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic300 (1986)
Projected traffic360 by 2030
Trucks0%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$400,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Old Mamalahoa HWY over Kaula Gulch built?

It was built in 1928, making it 97 years old in 2025. It was reconstructed in 2009.

What condition is Old Mamalahoa HWY over Kaula Gulch 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 June 2023.

How much traffic does Old Mamalahoa HWY over Kaula Gulch carry?

About 300 vehicles per day (1986 count).

How long is Old Mamalahoa HWY over Kaula Gulch?

The structure is 52 ft (15.9 m) long with a longest span of 17 ft (5.2 m) and a deck 16 ft wide.

Who owns Old Mamalahoa HWY over Kaula Gulch?

It is owned by the County Highway Agency.