CONTEXT:

The need for sanitation systems was recognized by the first civilizations of India, Babylon, Egypt, Crete, and Greece--going back as far as 1500 to 2500 BC. The cities of the ancient Greeks and Romans suffered from refuse and sewage problems worse than many large cities.  Even with new sanitation and waste disposal technologies at hand, lasting solutions are difficult to achieve due to population growth.

The modern era of waste management in the United States is only a little more than a hundred years old. It is within this relatively short period that modern waste treatment systems have been developed and widely implemented. These developments have made possible the control of many diseases and the improvement of health for the great majority of the population.

The wastewater treatment systems in every city are major engineering accomplishments. Although most people never give it much thought, the sewer systems under their streets required careful design, layout, and construction. This system of piping allows for an efficient and safe means of transporting waste and dirty water from anywhere in a city, to a centralized treatment plant where it can be broken down and disposed of properly. A close look at your local sewer system will provide an excellent example of the contribution of Civil Engineering to the health and well being of a society.

CHALLENGE:

EXPLORATORY
Arrange an interview with a Civil Engineer or City Manager to discuss some of the waste treatment problems in your region. If your teacher arranges a classroom visit by one of the above people, attend their presentation and participate in the discussion that follows. Ask questions about the history of your local sewage system and plans for future advancements.
 
INTERMEDIATE
Ask your teacher for the page that provides the "Sewer Layout Diagram." Pretend you are working for a construction company and you are looking at the engineering drawings for a proposed new sewage line. Your job is to make a drawing of each manhole so that construction of the sewer lines can begin. You must determine the angle at which each pipe enters the manhole, and the height of each manhole. This will require accurate measurements, to determine what is needed for each manhole, and the preparation of a "Take Off Sheet" for each of the manholes. If you follow the simple directions, provided in the "To Do" section, you will successfully complete this project and be rewarded with a promotion. Good Luck!
 
ADVANCED
Now that you have completed the Intermediate section of this project you can begin constructing this sewer system. Using your calculations and the material provided (clay. straws, tape, and paper towel rolls) begin the construction of each manhole. Inlet and outlet angles are very important in constructing the base. Follow your calculations carefully so the sewer system will make sewage coming into the system flow effectively to the treatment plant.

After completing this part of your model, use brown cardboard or stiff paper to show what the shape of the ground might be from one manhole cover to the next. You should make the slope of the ground between the manhole covers as gradual as possible. What additional information do you need to make this model more realistic?

MATERIALS:

EXPLORATORY
None 

INTERMEDIATE
None 

ADVANCED

• Modeling Clay
• Straws
• Masking Tape
• Paper Towel Rolls
• Scissors
• X-acto Knife
   

CRITERIA:

Your success on this Challenge will be based on your completion of the activities below. Three general criteria for your performance will be: your participation in the activity; the accuracy of your measurement and model construction; and the performance of your design.  Your teacher will help you understand how your performance will be graded.

EXPLORATORY
Conduct an interview with an engineer or city manager, and/or participate in Speakers presentation. Develop questions for the speaker. Participate in the field trip, if provided by your teacher.
 
INTERMEDIATE
Analyze the forms and drawings provided by your teacher and complete all worksheets. Determine all the distances and dimensions from the Sewer Layout Diagram and record them as directed. Calculate the dimensions and depth of each manhole based on the established slope of the sewer line. Determine the angles of the pipes entering and leaving the manholes and record them on a Take Off Sheet for each manhole.
 
ADVANCED
Follow the design and build a model sewer line. It should be sloped in accordance with the sewer diagram so sewage consistently flows in the proper direction. Under the supervision of your teacher, test your sewer line system by running a small amount of water through the lines. Make a presentation on your work and your sewer line.