Ames F2013-2018 Capital Improvements Plan (CIP) That Was Authorized by the Ames City Council in Spring 2013
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I. Authorizing Resolution Passed by the Wastewater Utility’s Governing Board for the Sponsored Project Application This project is included in the City of Ames F2013-2018 Capital Improvements Plan (CIP) that was authorized by the Ames City Council in Spring 2013. Enclosed with this application is the page from the CIP that specifically address this project. II. Letters of Support from Project Partners The Iowa Department of Natural Resources has served as a partner on this project. Enclosed with this application is a letter of support from Nate Hoogeveen, the River Program Coordinator. III. Letter from the Wastewater Utility’s Bond Counsel Indicating Concurrence with the Sponsored Project Concept Dorsey & Whitney, LLP serves as bond counsel to the City of Ames. Enclosed with this application is a letter of concurrence with the Sponsored Project concept. IV. Assessment of the Impacted Waterbody and its Watershed with Data that Supports the Identification of the Water Quality Problems to be Addressed. Iowa DNR Provided a copy of a Flathead Catfish Study which shows that for the South Skunk River, the 13th Street Dam in Ames, IA serves as an obstacle to passage. No Flathead Catfish have been sampled upstream of the 13th Street Dam since 1970. Sampling for other species of fish has shown similar results, including only one Channel Catfish since 1970. The South Skunk River page from the Flathead Catfish Study has been enclosed with this application. V. Discussion of Project Goals and Objectives In-stream Habitat Enhancements The proposed modifications to the 13th Street Dam will allow fish passage upstream to the Hannum’s Mill Dam. The Hannum’s Mill Dam is the only dam upstream preventing fish passage to the entire South Skunk River. The Oakland Mills Dam is 188 river miles below the 13th Street Dam. Access to headwaters on the Des Moines Lobe geological landform will be important for the fishery. The segments of river immediately upstream of Ames contain cobble and rock substrates that are not available in many other portions of the South Skunk River. The existence of the dam likely limits the populations for certain species that would typically be in place, such as deepwater overwintering ictalurids like channel catfish and flathead catfish. The period of sampling record upstream of the 13th Street Dam saw only a single channel catfish sample in 1970 with 30 subsequent years of records, and no flatheads during the same period. These would be the primary species to benefit. Additional species that are present downstream, but not upstream of the 13th St dam include Bullhead Minnow, Channel Shiner, Emerald Shiner, Freshwater Drum, Longnose Gar, Shortnose Gar, Shoal Chub, Slenderhead Darter, and Smallmouth Buffalo. Additionally, the Creek Heelsplitter and Paper Pondshell species of mussels would also benefit from biological connectivity resulting from this project. Installation of Natural Channel Design Techniques The proposed modifications to the 13th Street Dam will use natural channel design techniques including the strategic placement of weir boulders, base stone, and gradation stone to direct the flow as well as pool water and protect the river bank. These natural channel design techniques will help protect the river bottom and river banks during periods of high flow by reducing the concentration of kinetic energy immediately downstream of the dam. The highest velocities will also be directed away from the sides of the river and will be slowed downstream of the dam by installation of a j-hook configuration of natural stone. VI. Evaluation of Alternatives Considering the Unique Demographic, Topographic, Hydrologic, and Institutional Characteristics of the Planning Area Project Alternatives Many alternatives were considered since the inception of this project. Public meetings were held to receive stakeholder input and develop a design that accommodated those needs. The one constraint from the beginning was that the 13th Street dam cannot be removed altogether. The reason the dam was originally built was to provide groundwater recharge to the aquifer serving the City of Ames drinking water wells. During periods of drought, the dam has proven invaluable at mitigating the effects on the groundwater supply to the City of Ames. With removal of the 13th Street Dam eliminated as an alternative, the stakeholder needs were taken into account. The arched rock rapids design with weir boulders, base stone, and gradation stone was chosen because it used natural channel design techniques and it provide the greatest in-stream habitat enhancements to fish and mussels in the South Skunk River. The current design also will provide recreational opportunities for canoeing and naturalist groups, as well as eliminate the dangerous hydraulic circulation that has caused so many deaths throughout Iowa in recent years. In approximately the past two years, the project has become more expensive due to required hydrological modeling and increased materials costs. While determining whether to continue with the project, the City of Ames met with Nathan Young at the Iowa Institute for Hydraulic Research in Summer of 2012, to discuss alternative designs. It was determined at that time that, excluding dam removal, there are no lower-cost design alternatives that could be pursued that would provide the in-stream habitat enhancements, natural channel design techniques, as well as meet the other needs of the stakeholders. VII. Description of Practices to be Implemented with the Expected Water Quality Outcomes The Iowa Department of Natural Resources – River Programs has worked closely with the City of Ames to develop a design based on the principles outlined in various publications by Luther Aadland on the topic of Natural Channel Design. Enclosed with this application is documentation on the design for the project. VIII. Discussion of project locations, land ownership, and any plans for acquiring properties or easements The project is located in North River Valley Park upstream of 13th Street. The property is owned by the City of Ames and, due to its design footprint, no acquisition of property will be needed for this project. Figure 1 – Aerial of Low-Head Dam in City of Ames at North River Valley Park. Figure 2 - View of Low-Head Dam in City of Ames at North River Valley Park, looking north. IX. Identification of Any Other Organizations or Resources to be Involved in the Project and their Expected Contributions Other organizations that have been involved with this project include the Skunk River Paddlers, the Hawkeye Fly Fishing Association, and individual citizens. Verbal commitments of funding have been made to this project, from some individuals and groups, but no money has actually been donated at this time. X. Proposed Project Schedule with Major Milestones Project Event/Milestone Date Application for Sponsored Projects Funding Submitted July 19, 2013 Public Hearing November 14, 2013 Public Comments Closed November 21, 2013 Commission Meeting & Approval December 17, 2013 Complete Hydraulic Modeling January 2014 Begin Construction June 2014 Complete Construction September 2014 XI. Proposed Evaluation Procedures and Measures Biological and Physical Monitoring Data Several decades of fish population and community samples exist for sites upstream and downstream along the South Skunk River. Iowa DNR has indicated in past grant proposals that Channel Catfish and Flathead Catfish populations could be targeted for increased sampling in the future after modifications to this dam have been completed. This could also include tagged releases downstream of the 13th Street Dam. Monitoring for tagged releases downstream would provide verification that the proposed modifications were successful. LOW-HEAD DAM MODIFICATIONS PROJECT STATUS: Scope Change Cost Change City of Ames, Iowa Capital Improvements Plan Delayed DESCRIPTION/JUSTIFICATION This project will modify the low-head dam in North River Valley Park. The primary purpose is to reduce the risk of drowning due to a hydraulic recirculation downstream of the dam. Additional benefits of the improvements include increasing the recreational opportunities for paddlers and kayakers, and creating an opportunity for fish to migrate upstream past the dam. COMMENTS The low-head dam in River Valley Park serves an essential function during periods of sustained drought by pooling water in the primary recharge zone for the Water PlantRs Downtown Well Field. This type of dam has the potential to create a dangerous hydraulic recirculation downstream of the dam. The recirculation can trap a person below the surface and can lead to drowning in just a few feet of water. A conceptual proposal has been developed jointly between the City of Ames and the Iowa Department of Natural Resources that will achieve the primary goal of improved safety, while also providing additional recreational opportunities for paddlers and kayakers. The design would also facilitate the movement of fish upstream past the dam, helping to increase the upstream fish population diversity. The project was originally shown in the FY 10/11 CIP at an estimated cost of $150,000. The City received a grant award of $75,000 from the stateRs Low-Head Dam Public Hazard Grant program. Over the past two years, staff has been unsuccessful in receiving permit clearance for the original design concept. Work with the Iowa Department of Natural Resources and the Iowa Institute for Hydraulic Research has resulted in a design that should be able to receive permits from the necessary