Drainage and Flood Control

As a 30 year resident of northern Arizona, SWI is familiar with local drainage issues of the area and has modern solutions to combat the elements. For a more detailed list of relevant projects, please visit our contact page to request more information.

SWI was the lead civil engineer responsible for the drainage improvements of an existing drainage channel located adjacent to the Sunrise Vistas subdivision in Fort Mohave, Arizona. SWI’s scope of work included site topography, preparation and boundary survey for the channel property, drainage analysis and reports, and the preparation of the drainage improvement plans for over a half-mile of existing channels.

Due to the proximity of the existing drainage channels, the adjacent homes experienced flooding during heavy rainstorms. The original subdivision drainage design included drainage facilities that captured a portion of the flows. SWI utilized the existing facilities in the final design to include concrete weir structures maximizing the existing facilities effectiveness. The new channel design was sized to convey the 100-year storm to reduce the risk of flooding to these homes.

SWI provided creative design solutions by utilizing the existing concrete facilities and constructing weirs to slow down channel velocities thereby reducing sediment transport and erosion.

SWI identified the necessary property rights and ensured the project alignment was clear of all utility conflicts before the construction of new drainage facilities for the Rio de Flag by the U.S. Army Corps of Engineers. This included the preparation of complete plans, specifications, and cost estimates for the utility relocation effort and the acquisition of property rights for the construction of the $54 million Rio de Flag Flood Control project.

The purpose of this five-phase drainage project was to protect public infrastructure and private properties from flooding by Soldier Wash. SWI was the prime engineer for all phases of the project providing infrastructure design and storm water consultation for the City of Sedona. For the first three phases, SWI provided the design of replacement jersey barriers along the banks to increase channel capacity and prevent vehicles from being washed into the channel.  The fourth phase consisted of box culverts and channel improvements designed to convey a 25-year storm. The fifth phase replaced the arch culvert at Brewer Road.

SWI was the prime engineer and surveyor for this project in Bullhead City. SWI provided topographic surveying for the project site including the existing conditions of Goldrush Road and detailed topography for Montana Wash and two adjacent tributary washes. Utilizing the topographic survey, SWI performed the design for the reconstruction of Goldrush Road from Ramar Road to Silver Creek Road. The design included two box culverts, a large diameter culvert, and re-grading of the road profile to eliminate three low-water crossings and removing the roller coaster effect of the existing road profile. The design also included widening the road section and curb; gutter; and sidewalks to improve drainage conditions creating a safer high volume connector road.

SWI was also retained to prepare the US Army Corps of Engineers Jurisdictional Delineation and 404 Permit application.

SWI was tasked with preparing the Jerome Area Drainage Master Study (ADMS) using funding provided by Yavapai County Flood Control District. SWI provided the Town Council with extensive field observations and structure identification of five project locations. As a result of the investigations, SWI provided hydrology and hydraulic modeling, 15% plans, cost estimates, and the final ADMS report for review and acceptance by the Town and Yavapai County Flood Control District.

SWI worked with the town and Council to obtain public input for impacted areas. Using public input, SWI presented the Drainage Master Plan to the Council and Community.