Students learn about the organizational coordination and technical know-how necessary to respond to weather disasters. The small group activity explores the chemistry and environmental science behind innovative deicing products.

Grade Level

7-9 (may be adapted for younger or older students)

Materials

Discussion

When a blizzard or ice storm strikes, the people who work for your state and local transportation agencies respond to battle the elements much as an army responds to an enemy attack. When the meteorologists tell us that a storm is threatening our area, we implement our Emergency Action Plans. These plans detail who needs to do what to keep people safe during the storm and to get us moving again as soon as possible after the storm passes.

Our Emergency Operations Center (EOC) uses the latest computer technology to help us decide what we need to do, when, and where. We have sensors on the roads that tell us road temperatures, whether the road is wet or dry, and information about snow, ice, and deicing chemicals on the roads. This information is set by telephone lines to a remote processing unit, and then to a central computer at the control center.We put the highway condition data into our winter storm mapping system, where it is visually displayed on a statewide map. Our maintenance engineers receive this information on their laptop computers and use it to determine when and where to send snowplows and deicing equipment.

During a storm a lot of people need information fast. We have closed circuit television cameras on the major roads in the region that feed pictures of traffic into the EOC. We can see right away when an accident occurs or a traffic back-up starts. In some areas, you can see these live video images on the Internet or on cable tv. The State Police work with us at the EOC to send help immediately to people who have accidents or get stuck on the road during the storm. We can redirect drivers away from a problem area by reprogramming the traffic signals, and by broadcasting warnings on our changeable message signs and highway advisory radio. We notify the television, radio, and newspaper reporters about road and traffic conditions, so they can tell people at home or in their offices or cars.

We work with meteorologists to advise your school officials about road safety. They have to decide by about four o'clock in the morning whether to tell the school bus drivers to come to work. Sometimes we aren't sure at four o'clock what the weather is going to be like later in the day, so the schools delay opening for a few hours. If the weather clears, they won't have lost the whole day, Sometimes the storm has passed, but school is delayed for a few hours or a half-day to give us more time to clear away the snow. The school officials have to base their decisions on the safety of everyone in their school district. Sometimes roads are safe where you live, but school is closed because some of your classmates live where the roads are not clear yet.

We have new weapons in our arsenal to combat snow and ice storms that are the products of scientific and technical research. Modern snowplows are designed to plow snow more efficiently. Some "Smart Plows" are equipped with "Global Positioning Systems", which beam the plow's location to a satellite, and back down to our EOC so our operations managers know exactly where the snowplows are all the time. This helps us get plows where they need to be more quickly.

We are using new deicing chemicals that are more effective and less harmful to the environment than road salt. Road salt is not biodegradable, and can harm plants when it stays in the soil. Sometimes it leaches through the soil to groundwater, and makes the water undrinkable. Road salt also is corrosive, causing the steel in bridges and in cars to rust. Furthermore, it doesn't melt ice very effectively in temperatures below about 20 degrees Fahrenheit.

Activity I

The Physical Properties of Two De-Icing Materials

Purpose:

(1) To familiarize the students with the physical properties of both the traditional deicer, sodium chloride, and the newly marketed organic material, ICE-BANTM. (Steps 1-6)

(2) To compare the freezing temperature of the Ice BanTM /salt mixture with ice water (Steps 7-9).

In advance:

1. Order Ice Ban TM from manufacturer. Contact: Ray Marshall, ICE BANTM America, 1-888-423-2261. The product is the residue created by processing corn, and is completely safe and biodegradable. It will wash out of clothes.
2. Xerox the handout, making one for each student. (Staple together "The Physical Properties of Two De-Icing Materials;" "Conclusions;" and "Data Table.")
3. Set up the materials for each group:

One small beaker (50 ml) of Ice Ban TM
One small beaker (50 ml) of table salt
Two 200 ml (or similar sized) beakers
One teaspoon
One graduated cylinder or measuring cup
One thermometer (optional)
Enough ice (ice cubes or crushed ice) for one 200 ml beaker per group

Instructions for leading the classroom activity:

4. Tell the students to break up into activity groups (5-7 students) and give each student a handout. Instruct them to follow the steps under "Procedure."
5. Monitor each group to make sure they follow the instructions. The activity should take the students about 15-20 minutes to complete.
6. After the students have completed the procedures and filled in the Data Table, have them sit back at their desks. Direct their attention to "Conclusions." You may either ask each student to fill in their own answers and then discuss the answers as a group, or go directly to a group discussion

Discussion

Most of you should have found that the temperature of the ICE BANTM/salt mixture was several degrees lower than the temperature of the ice water. That is why it works as a deicer. We like to put deicers on the roads just before a storm to prevent snow and ice from sticking to the road. We call that "pretreating." We also put the deicers on after the storm, to help the snow and ice melt more quickly.

The manufacturer claims that ICE BANTM's freezing point is -36 degrees Celsius, compared to the 0 degrees Celsius freezing point of water. Regular road salt works well as a deicer down to about -6 degrees Celsius. [Someone may ask why the activity did not compare the ICE BANTM/salt mixture with a salt water mixture. The reason is that the differences in freezing points might not be apparent in such a small sample.]

Now let's talk about the conclusions. Most of you probably noticed that the salt water wasn't clear. That was because not all of the salt had dissolved into the water.

The ICE BAN TM has a molasses-like consistency and a distinct smell. If we added the ICE BANTM to a house plant, we wouldn't expect any effect. Adding a salt water solution to a plant would probably kill it, or at least make it pretty sick. That's one reason we are moving away from the use of road salt on the roads. It can harm plant life, and also leach into the soil and the groundwater supply.

If someone in your family needed an ambulance to go to the hospital during a bad winter storm, where the temperature was less than about 20 degrees Fahrenheit or -6 degrees Celsius, it might make a big difference whether we had treated the road with a alternative deicer. Those of us who work in the transportation industry take pride in doing our job well, so that you can travel safely.

This activity was developed by a public outreach partnership among the American Society of Civil Engineers, the FHWA, the Virginia Department of Transportation, and the Maryland Department of Transportation.

Activity II

(To Come)

Discussion

People who work in the transportation field have a major impact on people's lives. You may want to consider a career in transportation.

Many civil engineers work in the transportation field, designing and building roads, bridges, and transit systems. Engineers need a good mathematics and science background. Many scientists with backgrounds in chemistry, physics, electronics or biology work in transportation research to developing new equipment and products for transportation agencies to use. Maintenance workers, equipment operators, and construction workers also play vital roles, and are increasingly called upon to use new technology in their jobs. Transportation planners work with public officials and citizens to decide how a community wants its transportation system to operate and grow. Planners study social sciences and public administration. Public information professionals--who have good language skills and a basic understanding of science and technology--help transportation agencies communicate with the media, special interest groups, and the general public. All of these types of people work together as a team to solve transportation problems. When an emergency event such as a winter storm occurs, we can see how important their work is to everyone.

This activity was developed by a public outreach partnership among the American Society of Civil Engineers, the FHWA, the Virginia Department of Transportation, and the Maryland Department of Transportation.