Passionate, Practical, Creative Problem Solving

Ayres has carried out over 50 task orders over the course of two five-year master contracts to provide riverine design and review services through hydraulic and hydrologic analysis and design and fluvial geomorphic assessment across the northeastern quadrant of Colorado. Six tasks are in progress, including 1D and 2D modeling (3D also available), floodplain permitting, review, design support, field assessments, hydrology, scour, and countermeasure design.

Over several decades FHWA has trusted Ayres to develop courses and instructional materials to equip engineers around the nation with critical skills and tools to enhance infrastructure resilience through hydraulic analysis and design. Ayres has also provided personnel to deliver instruction around the nation and in virtual environments. Several of our staff have received NHI awards for their excellence as FHWA course instructors.

The City of Colorado Springs Stormwater Enterprise hired Ayres to design long-term channel stabilization for approximately 3,000 feet of Cottonwood Creek. Ayres’ survey and subsurface utility engineering operations supported this effort to reduce future maintenance demands along the creek. See the project site on Ayres Site View.

Region 1 services involved emergency flood and culvert support, including flood damage assessments, repair evaluations, and scour countermeasures for corridors including US 34 and 36. For Region 4, Ayres completed hydraulic design for the replacement of Front Range timber bridges. Services included 2D hydraulic analyses, scour calculations and countermeasures, and floodplain permitting.

Ayres designed a floating bulkhead for use at several spillways. Many dams have operating gates that require dewatering for maintenance or for periodic operation to confirm they can be fully opened during high flows. A floating bulkhead comprises caissons that can be placed in a reservoir, pinned together, and floated into position upstream of the spillway that is to be dewatered.

Ayres provided many services on Orono Dam, initially providing a walking safety inspection and updates to the emergency action plan. Ayres found low spots, erosion concerns, and gate bolt and drain issues. The City later called Ayres when Gate 1’s hoist failed and the fabrication company needed an accurate gate weight, cable length, and hoist capacity.  Ayres' ropes team climbed the gate, computed its weight, and analyzed pin and side seal friction.

Ayres designed improvements to Clam Falls Dam, which impounds the Clam Falls Flowage immediately downstream of the County I bridge. The existing dam consisted of an undersized slide gate spillway and a decommissioned powerhouse. Ayres designed post-tension anchors and concrete improvements to increase the spillway capacity and stabilize the powerhouse.

The first comprehensive assessment (CA) and Level 2 risk analysis in this five-year IDIQ contract involved Castle Rock Dam, which is 3.5 miles long and has 18 tainter gates. Over 200 potential failure modes were proposed; about 50 were developed and evaluated. This was the first formal risk analysis within FERC's Chicago Region and set the bar for others. Subsequent CAs involved six Wisconsin dams.

Building upon three previous Ayres stream rehabilitation/enhancement projects upstream, this project aims to analyze Fossil Creek between Lemay Avenue and Trilby Road in Fort Collins and design improvements that rehabilitate the natural stream channel morphology, reconnect floodplain areas, improve aquatic and riparian habitat, address erosion and sediment transport concerns, improve resilience, and protect Southridge Golf Course.

Ayres assisted Larimer County and the Big Thompson Watershed Coalition in mitigation projects to protect valuable assets at risk after the Cameron Peak Fire. This included design recommendations and construction oversight support at two severely impacted locations. Ayres worked with the County, landowners, and the NRCS to remove severe debris deposition and complete channel alignment designs for efficient conveyance of water and sediment.

Ayres is helping the Nevada DOT to comply with the FHWA's National Bridge Inspection Program Metric 18 pertaining to evaluating and managing scour around bridge piers and abutments. This includes organizing existing documentation, screening undocumented bridges, appraising bridges, and completing plans of action (POAs) for new scour-critical bridges. Ayres also is updating existing scour-critical bridges' POAs.

Ayres conducted a preliminary wetland assessment to assist with project design while the site was outside the growing season required for wetland delineation. Ayres completed an official wetland delineation during the following growing season and coordinated with the Wisconsin Department of Natural Resources to determine which wetlands were artificial and which were subject to regulation.

Mlsna Dam, a dry flood-control dam, was breached during a 2018 flood. Vernon County decided to decommission and remove the dam because of stability issues associated with its sandstone abutments and a history of recent dam failures in Wisconsin's Driftless Region. Ayres designed the dam removal and stream restoration.