Nason Creek is a Category 2 watershed in the Wenatchee River subbasin and it contains major spawning areas for ESA-listed spring Chinook salmon and steelhead. It is also a bull trout core area. Nason Creek has a high potential to increase salmonid abundance and productivity; therefore, the restoration of ecosystem function through floodplain reconnection is a priority. The primary habitat-limiting factors in Nason Creek are lack of habitat complexity and large woody debris (LWD) and that large sections of historical channel and floodplain have been disconnected from the present channel.

In Nason Creek, the largest impact on fish has been from human activities occurring outside of the main channel. Construction of roads, highways, and railroads has resulted in the disconnection of off-channel habitat and floodplains, and an increase in instream sedimentation. Roads, highways, and railroads have confined Nason Creek cutting off approximately 400 acres of side channels and oxbows and altering channel form resulting in a semi-braided system with severe aggradation. The confinement reduces LWD input, instream cover, instream habitat complexity, streambank stability, and temperature regulation. Today, Nason Creek has approximately 25% as much side channel habitat as nearby reference reaches. The priority actions in Nason Creek are identified as follows: protect remaining floodplain and riparian habitat; restore channel migration to historical function; improve fish access to oxbows and historical side channels where restoration is not possible.

The Nason Creek Oxbow Reconnect Project (N4) installed two fish-passable culverts within the SR 207 road prism to reconnect 1.15 acres of existing abandoned side channel habitat to the current Nason Creek main channel. The upstream and downstream oxbow connections were accomplished by replacing the existing (blocked) culverts under HWY 207 with 8-foot and 12-foot diameter CMP culverts respectively to restore year-round surface water connection to the oxbow. The project site is located on SR 207 approximately 4 miles from the intersection of HWY 2, near Lake Wenatchee.

The project provides year-round, off-channel habitat for juvenile salmonid species by reconnecting the floodplain oxbow. Biologically, the reconnected oxbow will provide off-channel refuge, rearing, and over wintering habitat for juvenile salmonids and other aquatic species. The project was completed in November 2009.