GMSWORKS-3 Peace River Side Channel Restoration - BC Hydro

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Table 6. Conceptual Construction Unit Rates and Costs Item Cost Rate/Notes 15T Track Hydraulic Excavator $125/hr all found 35‐85 m 3 /s hr 20T Track Hydraulic Excavator $150/hr all found 50‐100 m 3 /hr 25T 6W Off‐road Truck $100/hr all found 25‐50 m 3 /s short haul 75 kW Bulldozer $100/hr all found Grading, finishing Labourer $650/d Includes per diem Foreman $900/d Includes per diem Site Engineer / Environmental Monitor $1150/d Includes per diem Excavate and place $5/m 3 20T Excavator, single pass Excavate and short haul $10/m 3 Haul less than 500 m Excavate and long haul $15/m 3 Haul off site Access and tote road construction $10,000/km Clearing and rough grading Full bench graded road construction $100,000/km Cut/fill, grade and ballast Complexing wood debris – installed $150/m 3 Use 1 m 3 per m 2 structure area Live staking ‐ installed $7.50/m 2 Use 2 stakes per m 2 area Complexing boulders ‐ installed (1000 mm dia. = 1 m 3 ) $100/m 3 Use 0.5 m 3 per 2.5 m 2 area Site Isolation and Dewatering ‐ small $5,000 Site < 100 m 2 Site Isolation and Dewatering ‐ large $25,000 Site < 500 m 2 Channel Crossing (3‐1500 mm CMP) $10,000 Per site 7 Selected Side Channel Restoration Sites On this basis an initial selection of preferred restoration sites were identified prior to field inspection. This assessment was verified or modified based on field examination results. For the pre‐field assessment, areas within the side channels were digitized with polygons to provide areas based on defined channel widths. Road and access distances were scaled from orthophotos and based on existing roads and distances to sites. The locations of these areas are indicated on the appended overview map sheets and are listed in Table 7. A brief description of each of these sites and conceptual remedial options are presented below. Table 7. Identified Side Channel Restoration Opportunities (PCN to Pine River). PCN Name a Side Channel Length (km) Side Channel Area b (ha) Side Channel Type Priority 5.0R 2.4 1.8 Open Low 8.1R 4.8 45.1 Open Low 17.2L 0.5 1.0 Closed High 23L 0.6 0.2 Closed High 32L 2.6 15.6 Closed High Peace River Side Channel Restoration 22
40.5L 3.0 18.0 Ephemeral Medium 58L 2.8 5.0 Closed High 73.8L 4.6 9.6 Open High 85.3R 5.7 17.1 Open Medium 98.2R 3.9 12.5 Ephemeral Medium 102.5R 2.2 6.6 Closed Medium a L/R indicates bank looking downstream; distance is downstream of PCN b area estimated at minimum water elevations from photogrammetry c assessment based on collaboration of principal authors and report methodology 7.1 River KM 5.0R The site at River KM 5.0R consists of a 2.4 km long right bank 5 side channel located opposite Hudson’s Hope and upstream of Maurice Creek. This area is shown on Map sheet 1 of 11, which is appended to the report. This side channel complex contains three primary channels. The most northerly channel (closest to the main stem) is infilled with sediment and colonizing vegetation. The middle channel is seasonally active but was found to contain little flow in May 2009. The largest third channel is an open channel along the right bank. Localized bank erosion is occurring along the mid‐ to lower section of the third channel, and sedimentation is forming an obstruction that extends into the larger southern secondary channel. These materials, along with sediment supplied from Maurice Creek form a hydraulically smooth series of bars at the outlet of the largest secondary channel. Sediment accumulation also occurs at the inlet of this large channel and these materials have been observed to go dry during periods of low flow (Rick Pattenden, pers. comm.). This area is illustrated on Plate 4.2.2. The three side channels at this site mimic fish habitats provided in the main side channel (run/riffle complexes). Due to frequent dewatering, the secondary channels provide minimal fish habitat and are used only opportunistically when sufficient flows are present. The area is dominated by the cold‐clear water fish assemblage. Bull trout (juveniles), mountain whitefish (juveniles), and rainbow trout (juveniles), and slimy sculpin (adults) are the fish species that are most likely to use the area at present. Cold water temperatures may preclude use of this area for spawning/egg incubation by most species (mountain whitefish is the exception). The conceptual restoration plan is show on the Site Map 5.0R. Road access is available to Maurice Creek and excavation equipment could access the site during periods of low river flow. Approximately 750 m of road is required for access, of which half requires road improvement and the other half is open tote road across gravel bars. A water crossing at the side channel outlet will be required to access the site. 5 Right bank while looking downstream. Peace River Side Channel Restoration 23
Page 1 and 2: Peace River Project Water Use Plan
Page 3 and 4: Executive Summary This study was in
Page 5 and 6: Acknowledgements The authors would
Page 7 and 8: Table of Contents Executive Summary
Page 9 and 10: 1 Scope of Work The Peace River’s
Page 11 and 12: assessment purposes. Data, analyses
Page 13 and 14: Figure 1: Pre‐Regulation Peace Ri
Page 15 and 16: Hydro via telemetry, and will be ut
Page 17 and 18: channel must be sheltered from high
Page 19 and 20: These impacts have been recognized
Page 21 and 22: while the mainstem river area was e
Page 23 and 24: Physical criteria developed in this
Page 25 and 26: a) Inlet improvements for additiona
Page 27 and 28: Studies on the Nechako River indica
Page 29: Site isolation costs and contingenc
Page 33 and 34: The restoration concept includes: 1
Page 35 and 36: vegetation. The most serious limita
Page 37 and 38: A series of extensively infilled ch
Page 39 and 40: 7.10 River KM 98.2R Site 98.2R cons
Page 41 and 42: compiled at a common scale to docum
Page 43 and 44: Instream Flow Needs Workshop, Walde
Page 45 and 46: Site Summary and Cost Tables Peace

GMSWORKS-3 Peace River Side Channel Restoration - BC Hydro

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