If you’ve driven across Indian Bend Wash along Shea Boulevard in Scottsdale, know that the bridge there is among the 150 in Arizona that were recently deemed structurally deficient.

However, that designation is not all doom and gloom for motorists.

The American Road & Transportation Builders Association recently released its report on the most structurally-deficient bridges in the U.S. ARTBA said an analysis of U.S. Department of Transportation data finds there are nearly 235,000 U.S. bridges in need of some structural repair, rehabilitation or replacement, including 47,000 structurally deficient bridges that are in poor condition.

According to the Federal Highway Administration, a highway bridge is a public vehicular structure more than 20 feet in length that spans an obstruction or depression.

Arizona has the second lowest percentage of structurally-deficient bridges in the U.S. Its 1.8% only trails Nevada’s 1.4%.

Numbers-wise, of the 8,294 bridges in Arizona, 150 are classified as structurally deficient, the sixth least in the nation. To be structurally deficient means one of the key elements is in poor or worse condition.

The 150 is an improvement from 2014, when 223 were classified as structurally deficient.

“Safety is the priority,” Doug Nitzel, spokesman for the Arizona Department of Transportation, told the Daily News-Sun. “As part of our commitment to bridge safety, ADOT invests approximately $60 million each year in the state’s bridge preservation program, which includes funding for bridge improvement and reconstruction projects.”

The report says 19 of Arizona’s poorer bridges are on the Interstate Highway System.

In Rhode Island, 23.1% of its bridges are structurally deficient, the highest percentage in the nation. However, Iowa has the highest number of structurally-deficient bridges with 4,675.

Texas has the most bridges at more than 54,000, double the amount of the state with the second-highest, Ohio. And yet, only 1.3% of the Lone Star State’s bridges were deemed structurally deficient.

Of the most traveled structurally-deficient bridges in Arizona, only one in Maricopa County is the Shea Boulevard bridge over Indian Bend Wash. The bridge, built in 1976, sees about 48,700 daily crossings.

Keep in mind, structurally deficient does not mean a bridge is unsafe. It’s a measure of identified repair needs that engineers track.

Mr. Nitzel noted that the ARTBA report includes state and local bridges. For example, bridges that cross the Agua Fria River in the West Valley are considered local, and not under the jurisdiction of ADOT.

“It’s also important to point out that the bridge condition information in the report is actually what ADOT has provided (to the federal government) from our inspections of our bridges,” Mr. Nitzel stated. “The information is the result of our inspection findings, so it’s not a matter of taking action based on the report. We prioritize our bridge improvements based on the judgment of professional engineers.”

Less than one percent of ADOT’s inventory of more than 4,800 state highway bridges are listed as structurally deficient, Mr. Nitzel added.

Overall, Arizona has identified needed repairs on 1,944 bridges at an estimated cost of $1.4 billion, compared to 2,440 bridges that needed work in 2014.

John Schneidawind, a spokesman for ARTBA, said putting bridges on lists for immediate repairs depends entirely on the financial situation in each state.

“Typically, on average, states rely on the federal Highway Trust Fund for 50 percent of their transportation outlays,” Mr. Schneidawind told the Daily News-Sun. “That fund is becoming depleted because Congress hasn’t authorized an increase in the gas tax in 26 years. States also pay for bridge improvements through their own gas tax and other revenues.”

ARTBA says people can quickly send their Congress representatives an email asking to push for a permanent revenue solution to the Highway Trust Fund.

Closing bridges typically falls under the purview of state transportation directors, who are charged with regularly inspecting bridges and can close them at any time if they fail inspection, Mr. Schneidawind said.

ADOT listed the following as reasons its bridge inventory has one of the nation’s top ratings:

Many of its bridges benefit from modern engineering designs, since they are relatively young. That includes structures that carry higher volumes of traffic on Valley freeways,

ADOT has a thorough bridge inspection program, investing about $60 million in its bridge preservation program each year, and

The state’s relatively dry climate helps many bridges last longer before major repairs are needed.

“It’s also good news that we don’t have any of ADOT’s Valley freeway bridges listed as structurally deficient,” Mr. Nitzel stated. “A lot of hard work has gone into repairs in recent years to get us to that point.”