Finding of No Significant Impact for Rehabilitation of Grade Stabilization Structures S-27, S-31 and S-32 Papillion Creek Watershed, Sarpy County, NE

Introduction

The Rehabilitation of Grade Stabilization Structures S-27, S-31 and S-32 in Papillion Creek Watershed is a federally assisted action authorized for planning under Public Law 83-566, the Watershed Protection and Flood Prevention Act as amended by section 313 of Public Law 106-472, the Small Watershed Rehabilitation Amendments of 2000. An environmental assessment was undertaken in conjunction with the development of the supplemental watershed plan. This assessment was conducted in consultation with local, State, and Federal agencies as well as with interested organizations and individuals. Data developed during the assessment are available for public review at the following location: U.S. Department of Agriculture, Natural Resources Conservation Service, Federal Building, Room 152, 100 Centennial Mall North, Lincoln, Nebraska 68508-3866.

Recommended Action

Proposed is the rehabilitation to High Hazard Criteria of three grade stabilization structures, Papillion Creek Watershed structures S-27, S-31 and S-32 that protect the drainage areas of 152 acres, 249 acres and 223 acres respectively.

Effect of Recommended Action

Rehabilitation of the structures will meet state dam safety requirements for High Hazard Class (c) and prolong the life of the structures and pools for 100 years. The existing principal spillways would be removed and replaced, the auxiliary spillways would be widened, the top of dam would be raised to provide a combination of storage capacity and auxiliary spillway conveyance to pass the design storm without overtopping the dams, and some of the accumulated sediment would be removed from GSS S-27.

Sediment delivery to downstream areas will continue to be held back.

If there is a significant cultural resource discovery during construction, appropriate notice will be made by NRCS to the State Historic Preservation Officer and the National Park Service. Consultation and coordination have been and will continue to be used to ensure the provisions of section 106 of Public Law 89-665 have been met and to include provisions of Public Law 89-523, as amended by Public Law 93-291. NRCS will take action as prescribed in NRCS GM 420, Part 401, to protect or recover any significant cultural resources discovered during construction.

No endangered or threatened species in the watershed will be adversely affected by the project.

No significant adverse environmental impacts will result from installations. The construction process and temporary draining of the pool may cause minor inconveniences to local residents during construction.

Alternatives

Three alternatives were analyzed in this plan.

No Action alternative includes a sponsor's constructed breach. This alternative would remove a portion of the embankment necessary to establish stable overbank velocities. A series of drop spillway structures would be constructed to control the change in elevation at each structure.

Federal Decommissioning alternative would remove a portion of the embankment necessary to establish stable overbank velocities. A series of drop spillway structures would be constructed to control the change in elevation at each structure.

Rehabilitation to High Hazard Criteria alternative, the structures would be rehabilitated to current criteria and would be brought into compliance with state dam safety regulations for high hazard structures. The life of the structures would be extended for 100 years. Grade stabilization and sediment control would continue to be provided by the structure, pool and surrounding area.

Consultation-Public Participation

The Papio-Missouri River Natural Resources District submitted an application for assistance in May 9, 2003. The request was a result of local concern and interest in extending the service life of these aging watershed structures and addressing dam safety.

Scoping meetings were held September 30, 2004. An afternoon meeting was held involving interdisciplinary efforts. Nebraska Game and Parks Commission, Papio-Missouri River Natural Resources District, Nebraska Department of Natural Resources, U.S. Army Corps of Engineers, Environmental Protection Agency, Douglas/Sarpy County Extension Service, and the City of Bellevue were in attendance. An evening meeting was held with twenty-six local residents in attendance and 12 representatives from the NRCS, NRD and HDR Engineering, Inc. A second public meeting for residents was held March 3, 2005.

The environmental assessment was transmitted to all participating and interested agencies, groups, and individuals for review and comment on May 20, 2005. The public meetings were held to keep all interested parties informed of the study progress and to obtain public input to the supplemental plan and environmental evaluation.

Agency consultation and public participation to date have shown no unresolved conflicts with the implementation of the selected plan.

Conclusion

The Environmental Assessment summarized above indicates that this Federal action will not cause significant local, regional or national impacts on the environment. Therefore, based on the above findings, I have determined that an environmental impact statement for the Rehabilitation of Grade Stabilization Structures S-27, S-31 and S-32 in Papillion Creek Watershed is not required.