NewsHour Extra: Bridge Collapse May Be Warning Signal of U.S. Infrastructure -- August 8, 2007

Using NewsHour Extra Feature Stories

Overview: NewsHour Extra features stories can help students identify and interpret key issues in current events. This activity anticipates one class period, but the follow-up essay might be assigned as homework, or in another period.

Warm Up: Use initiating questions to introduce the topic and find out how much your students know.

Main Activity: Have students read NewsHour Extra's feature story and answer the questions on the reading comprehension handout.

Discussion: Use discussion questions to encourage students to think about how the issues outlined in the story affect their lives and express and debate different opinions.

Follow-up: Students can write an 500-word editorial on the topic expressing their views and send it to NewsHour Extra [extra@newshour.org] for possible publication.

Evaluation: Students are graded on their answers to reading comprehension questions and/or their editorial.

Story: Bridge Collapse May Be Warning Signal of U.S. Infrastructure, 08/08/07
http://www.pbs.org/newshour/extra/features/july-dec07/bridge_8-08.html

Initiating Questions:

1. Who is responsible for the bridges and roads we drive on?

2. Who makes sure that bridges and roads are safe?

3. What might make a bridge unsafe?

Reading Comprehension Questions: (click here for printout)

1. What happened in Minneapolis last week?

The eight-lane Interstate 35W bridge in Minneapolis collapsed Aug. 1 during evening rush hour traffic, falling more than 60 feet into the Mississippi River. Five people are known dead, nearly 100 were injured and eight people remain missing nearly a week later.

2. What kind of bridge is the I-35W?

Constructed between 1964-1967, the I-35W bridge is considered a truss arch bridge. The truss is a simple skeletal structure with no piers built into the river bed and a single steel arch over the 390-foot wide expanse of water. Before the collapse, up to 144,000 vehicles used the bridge each day.

3. Who inspects bridges in the United States? How was the I-35W rated? What does this mean?

The I-35W bridge, along with other U.S. bridges, had been inspected and rated by transportation officials. The Minneapolis bridge had been rated "structurally deficient" in 1990.

According to the Department of Transportation, such bridges need "significant maintenance attention, rehabilitation or replacement." But the agency considers them safe for use. Over 70,000 other U.S. bridges have this classification.

The National Bridge Inspection Program rates bridges so that states can prioritize money for bridge repair and replacement.

4. How will the Minneapolis event impact the way in which the government inspects bridges?

Last week's collapse has called into question the inspection system itself.

"They may well have been doing everything that has been prescribed in the national bridge inspection program. That may well not be enough," Mark Rosenker, NTSB chairman told reporters last week, TwinCities.com-Pioneer Press reported.

"There may be some failures in the reporting system that was done here in Minneapolis."

Federal officials have said the program will be reviewed, "top-to-bottom."

5. Are U.S. bridges safe?

But, Rosenker added, Americans should be confident that U.S. bridges are safe.

"I don't believe that they should be worried at all," said Rosenker, the Associated Press reported.

6. How has structural design changed since the I-35 W opened?

Structural design, since 1967 when the I-35W opened, has not changed much, Kurtz said, but computers have radically changed the ways engineers analyze the impact of traffic, snow, wind and other factors.

"Before you had hand calculations and approximations. Now, using a computer, you have fewer approximations," Kurtz said.

7. How has economics impacted bridge design?

But the biggest change in bridge design, according to Kurtz, is economics. Complicated designs, like those seen in truss bridges, are often too expensive to build now with the rising cost of labor in the United States.

"Every bridge in the 1930s was a truss bridge and it was economics. Metal was expensive then and they are very efficient in terms of materials. Materials have gotten cheaper adjusted for inflation but that's not the case for labor costs, which have gone up, even adjusted for inflation," Kurtz said.

Discussion Activity (more research might be needed):

1. Why do you think states are more likely to build new bridges and highways than to repair and maintain the ones they already have?

2. Do you think this bridge collapse will change how states spend their transportation money? Why or why not.

3. Examine and research the major bridges in your community. What is their design? When were they built? What is their safety rating according to the most recent inspections? Ask local officials, are they confident that these bridges are safe for general use?

Write a 300-500 word essay on any of these topics providing clear examples. Send your completed editorial to NewsHour Extra (extra@newshour.org). Exceptional essays might be published on our Web site.