Lower Jack Creek Wood Placement

Transcription

1 Lower Jack Creek Wood Placement Project Design and Implementation Plan June 22, 214 Prepared By: Project Location: Project Ownership: Project Objectives: Project Permits: Implementation: Funding: Curry Soil and Water Conservation District & Swanson Ecological Services, LLC Jack Creek Chetco River confluence to South Bank Chetco River Road T4S, R13W, Section 34 Latitude , Longitude Freeman Rock, Inc. Contact: Ted Freeman (1) Create winter rearing habitat for juvenile salmonids (2) Create cover and resting habitat for adult salmonids (3) Stabilize approximately 15 feet of eroding stream bank (4) Remove invasive plants from the riparian area (5) Interplant native riparian shrub and tree species in the riparian area Issued (NWP /1) The Lower Jack Creek Wood Placement project was included in Freeman Rock, Inc. s removal-fill permit for gravel extraction Scheduled for the 215 instream work period (July 15 th through September 3 th ). Logs will be sourced from the Dewald s Winchuck River Ranch and trucked to the site. Freeman Rock, Inc. will use their equipment to install the log structures and remove Himalayan blackberry. Curry SWCD staff will oversee the wood placements, and follow up with herbicide treatment of the blackberry and interplanting of the riparian reserve Wild Rivers Coast Alliance (WRCA) funding has been secured for the harvest and transport of the logs, and will partially offset Freeman Rock Inc. s placement costs; WRCA funds will also compensate the Curry SWCD for project management. Riparian treatments are unfunded at this time Project Overview The Curry Soil and Water Conservation District will partner with Freeman Rock, Inc. to construct up to ten (1) large wood structures in lower Jack Creek; to improve instream habitat for adult and juvenile salmonids. The project area extends from the South Bank Chetco River Road (County Road) downstream approximately.47 miles to the confluence of Jack Creek and the Chetco River (see attached plan view map). Within the project area the County Road parallels Jack Creek on river left (looking downstream), and at places the toe of the road fill defines the left bank of the stream. Wood Placement Locations The locations of the wood structures were chosen based on the morphology of Jack Creek, and the location of the channel relative to the fill slope of the County Road. Wood structures will be built in conjunction with existing lateral scour pools and active overflow channels, to increase instream

2 cover, pool depth, and pool frequency; in secondary channel habitat that provides juveniles refugia during high flow events; and along a segment of eroding stream bank that extends into Freeman s pasture. To prevent damage to the County Road, wood structures will not be built where there is less than one active channel width between the toe of the road fill slope and the existing stream channel. Wood Placement Construction Within the project area the Ordinary High Water (OHW) stream channel averages feet in width and the channel slope is approximately 1%. Mobilizing wood to the project area that is of sufficient length to remain static on its own accord is not feasible given the OHW channel width and the influence of the Chetco River (backwatering and flooding); so wood structures will be built by burying approximately 75% of each log into the streambanks and, where needed, using ballast rock to counter the buoyancy of the wood; or, where feasible, using existing riparian trees to wedge the logs in-place (see Cross Sectional drawings with typical wood structure designs imposed). The logs will average 45 ft in length and inches in diameter, and approximately 5% of the logs will have rootwads attached. On average each structure will place 6 cubic yards of wood and up to 2 cubic yards of ballast rock into the OHW channel, for a proposed total fill below OHW of 8 cubic yards. The logs will be harvested from the Dewald s Winchuck River Ranch, trucked to the project area on log trucks, and staged in Freeman s pasture on river right. An excavator will be used to build the wood structures, which will be done from within the stream channel at the downstream sites (this segment of channel typically dewaters by mid-summer), and from top-of-bank at the upstream sites. The excavator will also grub Himalayan blackberry from approximately 25 ft of riparian area located immediately downstream of the County Road, on river right. Freeman Rock, Inc. will supply and operate the machinery used to off-load the logs, build the structures, and remove the blackberry. If funding can be secured, the Curry SWCD will treat the blackberry with herbicides in the first two seasons post-implementation, and will interplant the project area (~12.1 acres) with native trees and shrubs (a planting plan will be developed once funding is secured).

3 ive 1 Miles r CROSS SECTION 1 Ch or e tc S B A NK 1 Ja ck C RD 2 Feet D Cross Sections Roads Streams LR Large Wood Placement Sites L BE Legend re ek MP CA CHETCO CROSS SECTION 3 CURRY COUNTY CROSS SECTION 2 Prepared by Erin Minster, Curry SWCD, 6/13/214. Y:\Data Management\Surveys\Total Station\Survey Projects\LowerJackLWP214 Base map: 21 NAIP source USDA-FSA overlayed on lidar derived hillshade, Lidar Data Source: DOGAMI Contour Interval: 2 ft, lidar derived

4 FEET (ARBITRARY DATUM) RL 51 Cross Section RR FEET OHW = INDETERMINATE, JACK CREEK CHANNEL IS WITHIN THE LARGER FLOODPLAIN OF THE CHETCO RIVER PROPOSED LOG PLACEMENT--GENERALIZED PIN LOGS Prepared by Erin Minster, Curry SWCD 6/13/214 Surveyed 5/8/214 using Nikon Total Station, not survey grade for planning only.

5 FEET (ARBITRARY DATUM) RL Cross Section OHW RR FEET OHW = ORDINARY HIGH WATER PROPOSED LOG PLACEMENT--GENERALIZED PIN LOGS BALLAST ROCKS (BOULDERS) Prepared by Erin Minster, Curry SWCD 6/13/214 Surveyed 5/8/214 using Nikon Total Station, not survey grade for planning only.

6 Cross Section 3 RL RR FEET (ARBITRARY DATUM) OHW FEET OHW = ORDINARY HIGH WATER PROPOSED LOG PLACEMENT--GENERALIZED PIN LOGS Prepared by Erin Minster, Curry SWCD 6/13/214 Surveyed 5/8/214 using Nikon Total Station, not survey grade for planning only.