US Bridges

99th Ave over Drainage Ditch

Fair

Maricopa County, Arizona · 250 N of Grand Ave · Structure no. 09666

Built
1972
53 years old, rebuilt 1977
Condition
Fair
inspected December 2022
Type
Culvert
Concrete
Length
47 ft
3 main spans
Daily traffic
13,988
2020 count
Owner
County
County Highway Agency

About this bridge

99th Ave over Drainage Ditch is a concrete culvert carrying 99th Ave over Drainage Ditch in Maricopa County, Arizona. It was built in 1972 and reconstructed in 1977, so it is 53 years old, older than the Arizona average of 47.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 13,988 vehicles a day, roughly 10% of them trucks, projected to reach 13,998 by 2040. The structure is 47 ft (14.3 m) long. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
Carries99th Ave
CrossesDrainage Ditch
Location250 N of Grand Ave
RouteCounty Highway 0
CountyMaricopa County
StateArizona
Coordinates33.59827, -112.27157
Functional classUrban Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionDecember 2022
Inspection intervalevery 36 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating75.9 US tons
Inventory rating45 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans3
Design loadHS 20
Structure length47 ft (14.3 m)
Longest span15 ft (4.6 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic13,988 (2020)
Projected traffic13,998 by 2040
Trucks10%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was 99th Ave over Drainage Ditch built?

It was built in 1972, making it 53 years old in 2025. It was reconstructed in 1977.

What condition is 99th Ave over Drainage Ditch in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in December 2022.

How much traffic does 99th Ave over Drainage Ditch carry?

About 13,988 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is 99th Ave over Drainage Ditch?

The structure is 47 ft (14.3 m) long with a longest span of 15 ft (4.6 m).

Who owns 99th Ave over Drainage Ditch?

It is owned by the County Highway Agency.