HR Green Wins Multiple Iowa ACEC Engineering Excellence Awards, Including Grand Place Award
HR Green is pleased to announce multiple projects received 2022 Iowa Engineering Excellence Awards which recognize the year’s most notable engineering achievements. The awards recognize engineering firms and their clients for projects that demonstrate an exceptional degree of innovation, complexity, achievement, and value.
The winning projects are:
- WRA Eastside Interceptor, Des Moines Metropolitan Wastewater Reclamation Authority – Grand Place Award
- The Urban Loop – I-80/I-35 & IA 141 and Adjacent Interchanges, Iowa DOT – Honor Award
- Mahaska County Bridge Replacement Using ABC Techniques, Iowa DOT – Engineering Achievement Award
WRA Eastside Interceptor
There were eight major segments of construction projects broken out for the overall project. Segments 1 through 5 encompass a gravity interceptor sewer from Union Park, through the east side of Des Moines, to the Wastewater Reclamation Facility (WRF). Segments 6 and 7 encompass a 42” diameter pressure force main from the Westside Pumping Station site to the gravity sewer at Union Park. Segment 8 involved the construction of a new High Flow Pump Station on the Westside Pumping Station property and was designed to provide an additional capacity of 40 mgd. HR Green provided engineering services for the $24.8M Segments 6-8.
The WRA Eastside Interceptor helps address known capacity deficiencies of the Westside Interceptors and increase the system’s capacity to effectively and efficiently convey the flow of wastewater for the Des Moines metro area for decades to come.
The Urban Loop
The I-80/I-35 to IA 141 flyover bridge is the cornerstone element to resolve congestion and safety challenges at the convergence of I-80 and I-35 with Iowa Highway 141 (locally known as Rider Corner and now known as the Urban Loop) in the Cities of Urbandale, Grimes, and Johnston in the northwestern quadrant of the Des Moines metro area. Not only is the flyover a critical element of the overall interchange design, but the planning and design of adjacent interchanges were needed to address several corridor constraints, multiple construction staging and safety challenges, geotechnical challenges, as well as accommodate a future collector-distributor concept parallel to the I-80/I-35 mainline.
Mahaska County Bridge Replacement Using ABC Techniques
The Mahaska County Bridge Replacement Project replaced the existing 140′ long continuous concrete slab bridge constructed in 1965. During the concept phase of Mahaska County Bridge Replacement project, the benefits of conventional versus ABC approaches to construction were considered. The BSB, the Design Bureau, and District 5 followed the evaluation procedure outlined in the Bridge Design Manual to calculate an ABC Rating Score. The ABC Rating Score is a numerical value from 0 to 100, indicating the viability of bridge construction projects considering ABC concepts. The higher the score, the more suited a project is for ABC. Bridges with a score of 50 or more are automatically further evaluated for consideration of ABC techniques. The ABC rating score for this project was 57.
The goal of the Mahaska County Bridge Replacement project was to save user costs and reduce maintenance costs by implementing ABC techniques to reduce the road closure period to a maximum of 21 days. The final construction cost was $70,000 less than the engineers’ estimate of $4.85 million. The new bridge opened to traffic after being closed for only 19 days, two days ahead of schedule.