Mission/Rock Creek Floodplain Restoration, Phase 3

The Mission / Rock Creek Floodplain Restoration Phase 3 project is located in the Lapwai Creek watershed near Jacques Spur, Idaho. Project funds were used to install steelhead habitat improvement measures on two work sites in the lower Clearwater River drainage - Mission and Rock Creeks.

Treatments on Mission Creek (site 1747) resulted in the protection and restoration of steelhead habitat. Streambank erosion treatment occurred on 0.03 miles of stream using bank shaping and placement of rock and wood. Riparian vegetation was installed on both sides of a 0.14 mile reach and weed control occurred on 2.35 acres.



In 2019 a flood event occurred which deposited gravel and large wood at the site. This event resulted in the natural creation of gravel bars and two pools, and improved the site for spawning use. Consequently, the two instream structures originally planned were no longer needed, and the length of stream of being treated was shortened.



This site was originally planned for 0.38 mile of fence to protect riparian plantings from wildlife. However, no fence was installed due to an existing perimeter fence around the parcel which provides some protection from wildlife, and the fencing needs at the Rock Creek worksite were deemed to be greater.



Treatments on Rock Creek (site 1918) resulted in the restoration of 0.6 miles of Rock Creek, a tributary to Mission Creek. Levees were removed and floodplain was reconnected through the creation of two floodplain benches. The number of instream structures increased from 35 proposed to 49 installed due to ROW changes made by the county road department. Instream structures were installed using rock, logs, and rootwads to form scour pools for juvenile steelhead. Streambank protection was not a proposed action but was added when 2019 high flows eroded 0.02 mile along a county road in the project area. Logs, toe rock, and plantings were used to stabilize this area. Riparian vegetation was planted on 4.83 acres of floodplain (Proposed metrics for planting were not included due to an error in the original application.)



Fencing was not planned at this worksite due to the lack of wildlife presence at this location. However, during construction and planting, it became apparent that the white-tailed deer population was significant and they were browsing the newly planted vegetation each evening. The fencing treatment proposed for Mission Creek was installed on Rock Creek due to its greater browsing pressure with 0.44 miles of fence installed.



Additional work is planned within the stream channel in phase 4, which will occur after 2 to 3 winter high flow events.



This contract received amendments to extend the end date due to numerous delays caused by COVID-19 restrictions.



Partner contributions (match) were less from Nez Perce County Road and Bridge Department than originally planned as it took less time than expected to complete their component of the project.

The purpose of this project when completed is to improve instream aquatic habitat, reduce sediment transport to Mission Creek, and increase floodplain connectivity. This project will implement priority actions in a priority watershed (Lapwai Creek) as directed by the NMFS 2016 proposed recovery plan for the recovery of Snake River steelhead DPS, Clearwater River MPG, and Lower Mainstem Clearwater River population.



Lapwai Creek is a priority watershed for restoration implementation in the Lower Mainstem Clearwater River steelhead population, Clearwater River MPG, Snake River steelhead DPS and has been identified as such in the NMFS 2016 proposed recovery plan. When implementation of the resulting designs occurs, the work will address priority actions identified in the proposed recovery plan.