Detention Pond Project Description: This project aims to design a stormwater detention pond on the site assigned to your group in the lab. The detention pond must provide minimum storage of 50,000 gallons, meet all design criteria, and minimize the project's total cost. Figure 1 shows the embankment design criteria.

Figure 1. Embankment Design Criteria

The detention design criteria are:

• The maximum side slope of the pond embankment on the upstream side of the dam (inside the pond) is 1:2
• The maximum side slope of the pond embankment on the downstream side of the dam (outside the pond) is 1:3
• The crest of the pond embankment should be 10 ft. wide to accommodate a vehicle.
• The water level must be at least 1 ft. below the crest of the pond embankment.
• The soil used to construct the pond embankment must be compacted, and the fill or loose soil volume is reduced by 15% when compacted.
• The side slopes of the pond embankment must be protected from erosion.
• The pond embankment must have a spillway not placed on compacted material.
• The minimum width of the spillway is 10 ft.

Typical costs for materials and services are:

• On-site cut and fill: $2.50/yd.³
• Off-site fill: $5.00/yd.³
• Off-site cut: $3.00/yd.³
• Concrete (delivery and labor): $100/yd.³
• Pond embankment protection: sod $0.25/ft.², hydro-seed - $0.17/ft.², dry seed $0.10/ft.²,
                                               stone $ 1/ft.², concrete $ 2/ft.²

These cost estimates are preliminary. Over time, as additional cost items are required, a current list of costs will be posted on the class web page. Please keep the proj As additional cost items are required, a current list of costs will be posted on the class web page over time. Please check the web page routinely to keep the project's status up to date. In addition, all supplemental information posted on the web page will be announced in class.

The detention pond project poses several challenges to each group: developing an accurate topographic survey of the site, designing and configuring the detention pond, locating the detention pond on the site such that cut-and-fill is minimized, and developing a sound engineering solution that meets the design criteria while reducing the project cost.

The analysis skills required in this project are topographic computations for contour maps, traverse computations for estimating areas, cut-and-fill for the pond and the embankment, and the configuration of the pond spillway. Spreadsheets should be developed to compute information for topographic maps, traverse areas, and cut-and-fill minimization.

Project Resources:

Groups may seek information about materials and design from: the UM Civil Engineering faculty (Drs. Claudio Meier, David Arellano, and Charles Camp), professional organizations, practicing engineers, and available publications.

This website was originally developed by Charles Camp for CIVL 1112.
This site is maintained by the Department of Civil Engineering at the University of Memphis.
Your comments and questions are welcomed.