The upper Omak Creek watershed had several undersized culverts replaced:

UO-1, one undersized culvert was removed and replaced with an appropriately sized 9' culvert.
UO-2, one undersized culvert was removed and replaced with an appropriately sized 9' culvert.
UO-3, one undersized culvert was removed and replaced with a 300' road decommission.
UO-4, one undersized culvert (NWNW S3 T32 R29) was removed and replaced with an appropriately sized 3' culvert.
UO-5, one undersized culvert was removed, (SESW S17 T33 R29), the channel widened and sloped to engineered specifications and a new 30' bridge installed.
UO-6, one undersized culvert was removed, (SWNW S20 T33 R29), the channel widened and sloped to engineered specifications and a new bridge installed.
UO-10, one undersized culvert was removed and replaced with a 41' single span bridge appropriately.
UO-11, one undersized culvert was removed and replaced with an appropriately sized 8' culvert.
UO-12, one undersized culvert was removed and replaced with an appropriately sized 8' culvert.
UO-13, one undersized culvert (NWNE S34 T33 R29) was removed and replaced with an appropriately sized culvert.
Jim Creek Culvert, one undersized culvert, (just downstream of UO 5 & 6) was removed and replaced with an appropriately sized 6' culvert

One of the main factors limiting salmonid production in the Omak Creek and connected tributaries is high proportion of fine sediment. The source of fine sediment is primarily from unimproved road surfaces. In addition to decommissioning roads, the Tribes Fish & Wildlife staff have worked with Environmental Trust to identify undersized drainage structures which are a threat of being over-topped and washing out. These structures are being replaced with a larger diameter length of corrugated metal pipe (cmp) or a pre-cast bridge. The anticipated result is to reduce the risk of the road sections at these undersized drainage structures from washing-out thereby depositing large volumes of road fill into the stream channel. In time it is anticipated that the volume of fine sediment in Omak Creek will be measurably reduced thereby resulting in an increase in egg-to-fry survival.