he team created several potential solutions and scored them based on the criteria and constraints of the project. It was determined that solution 2 was the best choice for the final design, due to improvements in the stream and its low cost. The design solutions and scoring matrices can be found below.
Map of three potential design alternatives.
Solution One: Keep the stream as it is, inside the culvert, but to improve the existing conditions surrounding the stream. The design solution would clean up the area while preserving the riparian vegetation to insure the stream will still be protected by its natural surroundings. The area of this design solution would only be the currently open portion of the stream that runs through the neighborhood.
Solution Two: Combination of the first solution with a partial daylighting of the stream. The portion of the stream that would be daylighted would be the area behind the Coca-Cola plant. The open portion of the stream running through the neighborhood will be cleaned up as stated in the first solution, but when the stream reaches the plant, it will be taken out of the culvert and rerouted to a natural drainageway located on the north and east sides of the plant.
Solution Three: Daylight behind the Coca-Cola plant as well as a section of land in the neighborhood, specifically 7th to 5th Street. This design will still include the benefits from daylighting behind the Coca-Cola plant, but it will also incorporate a daylighted stream in mostly vacant areas of the land in the neighborhood.
Solution Four: The ideal condition- to daylight the entire stream. This entails daylighting the stream in the neighborhood from 10th to 5th street as well as the area behind the Coca-Cola plant. The stream would flow through parts of the neighborhood and under roads.
Each of the solutions mentioned above will also involve a community outreach portion. An information packet for the community with information on how they can decrease their stormwater fees, and how daylighting Cedar Run will benefit them will be disturbed. An estimate of the amount of runoff that the proposed project can mitigate will also be presented to the community. Presenting this educational information to the community will hopefully increase the community’s awareness and sense of pride in Cedar Run.
Solution Two: Combination of the first solution with a partial daylighting of the stream. The portion of the stream that would be daylighted would be the area behind the Coca-Cola plant. The open portion of the stream running through the neighborhood will be cleaned up as stated in the first solution, but when the stream reaches the plant, it will be taken out of the culvert and rerouted to a natural drainageway located on the north and east sides of the plant.
Solution Three: Daylight behind the Coca-Cola plant as well as a section of land in the neighborhood, specifically 7th to 5th Street. This design will still include the benefits from daylighting behind the Coca-Cola plant, but it will also incorporate a daylighted stream in mostly vacant areas of the land in the neighborhood.
Solution Four: The ideal condition- to daylight the entire stream. This entails daylighting the stream in the neighborhood from 10th to 5th street as well as the area behind the Coca-Cola plant. The stream would flow through parts of the neighborhood and under roads.
Each of the solutions mentioned above will also involve a community outreach portion. An information packet for the community with information on how they can decrease their stormwater fees, and how daylighting Cedar Run will benefit them will be disturbed. An estimate of the amount of runoff that the proposed project can mitigate will also be presented to the community. Presenting this educational information to the community will hopefully increase the community’s awareness and sense of pride in Cedar Run.
The general criteria matrix, with each solution scored.
The cost matrix, with each solution scored. Cost scores were assigned based on an engineer's best personal judgement.
The overall decision matrix. Scores from the above matrices were complied into the matrix below.
The team surveyed two cross-sections of Cedar Run directly upstream of the Coca-Cola plant.
The team used three different methods to determine the flow generated by Cedar Run during different storm events. The three methods used were Anderson, SCS Curve Method, and TR-55. The flow values generated by TR-55 were chosen and used for subsequent calculations. TR-55 was chosen because the values fell between the values generated from the other two methods and was comparable to flow values generated from comparable watersheds.
The team is currently sizing the channel using the Two-Stage Channel Design from Part 654 Stream Restoration Design National Engineering Handbook. A cross section of a two-stage channel can be found below. A two-stage channel was chosen over a trapezoidal channel because of the benefits of improved drainage and ecological function.