Project Background
Abstract
This project analyzes the various drainage factors that could affect the transmittal of stormwater going through the culverts at the intersection of Steves Blvd and the Fanning Wash. An analysis was needed at this intersection due to clogging of the culverts, as well as sedimentation being found at the inlet of the three culverts. Through this analysis the existing conditions will be analyzed for the channel and culverts by also looking at upstream and downstream conditions to produce an accurate model of the flow path. The analysis will determine the runoff based off of different storm events, and predict where flooding could occur within our project limits. Proposed modeling will guide the recommendations to improve the existing drainage conditions where modifications will be made on the channels and culverts to determine if these modifications will help or hurt the existing channel or culvert. Considerations will be made for the downstream conditions to show how the proposed conditions at the intersection will affect the stormwater flow upstream and downstream of our project area. All existing and proposed designs will be produced using the City of Flagstaff Stormwater Design Manual. The sections below explain the work scope, project constraints, proposed schedule of design work, and the cost of engineering services.
Project Location
The three figures depicted below show the project location and extents of the Fanning Wash at the intersection of Steves Blvd.
Overview of Site Photo Credits: Google Maps
Zoomed in Location of Site Photo Credits: Google Maps
Site Location within Flagstaff Photo Credits: Google Maps
Project Tasks
The project work scope included seven major tasks listed below:
Task 1: Site Investigation
Task 1.1: Field Visit and Initial Assessment of the Intersection
Task 1.2: Field Surveying
Task 1.3: Documentation of Existing Structures/Topography
Task 1.4: Review Existing Approved Plans
Task 1.5: FEMA Floodplain Information
Task 2: Hydrologic Analysis
Task 2.1: Analyze Previous Precipitation Data
Task 2.2: Watershed Delineation
Task 2.3: Determine Natural Runoff
Task 3: Hydraulic Analysis
Task 3.1: Analyze Previous Drainage Studies
Task 3.2: Determine Existing Channel and Culvert Capacity
Task 3.3: Design Recommended Channel and Culvert Modifications
Task 4: Construction Plans
Task 4.1: Existing Floodplain Map
Task 4.2: Existing Topographic Survey with Culverts
Task 4.3: Existing Channel Plan and Profile
Task 4.4: Proposed Channel Plan and Profile
Task 4.5: Existing and Proposed Channel Cross Sections
Task 4.6: Channel Design Details
Task 4.7: Culvert Design Details
Task 4.8: Erosion Protection Design
Task 4.9: Project Notes and Specifications
Task 4.10: General Project Details
Task 5: Evaluate Project Impacts
Task 5.1: Environmental Impacts
Task 5.2: Societal Impacts
Task 5.3: Economic Impacts
Task 6: 30%, 60%, 90% and Final Deliverables
Task 7: Project Management
Task 7.1: Project Meetings
Task 7.2: Schedule Management
Task 7.3: Resource Management
Existing Outlet Culvert Locations at the Intersection Photo Credits: Cole Kelley
Project Constraints
The four primary project constraints are shown below:
Surveying of Private Property: land boundary surveys, property corners, and drainage easements
Geotechnical Engineering: subsurface hydrology, soil properties through various testing, and compaction
Traffic Analysis: traffic flows, and roadway speed limit
Roadway Analysis: pavement design, roadway width, and other roadway geometric conditions
Project Schedule-Gantt Chart
A Gantt Chart was produced to show when the necessary project task will be completed, to comply with deadlines set out by the course. Milestones were identified to ensure the project stayed on track with the schedule. The critical path for our design is displayed below in red.
Project Staffing
The design team plans to spend a total of 795 hours on the project to complete all of the major tasks shown above. The table below depicts the estimate for the engineering design services.
Project Costs
The project was projected to cost about $76,000 for all aspects of the design which included personnel, travel, supplies and licenses for the different softwares needed for analysis.
