M EMORANDUM O CTOBER 6, 201 6

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Gerald Perkins
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M EMORANDUM O CTOBER 6, 201 6 TO: FROM: SUBJECT: BOARD OF DIRECTORS ERIC KUHN, GENERAL MANAGER PETER FLEMING, ESQ. DON MEYER, P.E., RAY TENNEY, P.E. WOLFORD AND ELKHEAD RESERVOIR OPERATIONS This memo summarizes 2016 Wolford and Elkhead Reservoir operations and maintenance activities.

1 M EMORANDUM O CTOBER 6, TO: FROM: SUBJECT: BOARD OF DIRECTORS ERIC KUHN, GENERAL MANAGER PETER FLEMING, ESQ. DON MEYER, P.E., RAY TENNEY, P.E. WOLFORD AND ELKHEAD RESERVOIR OPERATIONS This memo summarizes 2016 Wolford and Elkhead Reservoir operations and maintenance activities. No Board action is required. Wolford Reservoir Operations The graph below shows recent Wolford operations. April-July inflow was 57,300 acre-feet, or 106 percent of average. The reservoir is 9 feet down from full pool, nearing the winter target of 10 ft down per the operating plan, storing 53,900 acre-feet (12,000 acre-feet down from full).

2 Page 2 of 7 10/06/2016 In May the reservoir spilled for the first time since 2014, and remained full through late July, when releases began from the 6,000 acre-feet Recovery Program pool. Subsequent to these releases outflow was adjusted to meet the winter target, benefiting flows in the 15 Mile Reach. Outflow will be reduced to the minimum release of 20 cfs this week in anticipation of the brown trout spawn on Muddy Creek below the reservoir. Maintenance Activities at Wolford Mountain Reservoir Muddy Creek Stream Maintenance 2016 Work The second phase of the bank stabilization project on Muddy Creek in the wetlands mitigation area downstream of the reservoir included work at two sites so far this year, and work will begin next week on piping the East Ditch from the headgate on the Swab Ditch to the East Ditch Syphon. Staff is working with our consultants, Ayres, on plans for next year s sites including a siphon that has become exposed and another siphon at risk. Reservoir Fishery Efforts to remove Northern Pike from the reservoir include a River District sponsored CPW Spring gill netting program, run mostly by volunteers, targeting Pike in the upper inlet areas, and a $20 bounty program for the general public. During the last two years the netting program yielded only a total of 21 Northern Pike, and no bounties have been claimed by the public. Kokanee Salmon eggs will be harvested late October again this year. Kokanee traps dispersed on the shoreline near the recreation area are emptied and the eggs are stripped from the females. The stripped fish are given to the public, a popular program. In 2014 Wolford produced 1.78 million kokanee salmon eggs, almost 18 times the number of eggs that are needed to restock it, but last year less than a million were harvested. The main reason the kokanee fishery is thriving at Wolford as compared to other reservoirs such as Granby and Blue Mesa is thought to be the lack of predatory lake trout. Ritschard Dam Deformation Investigation The embankment continues to deform at established rates, with monthly monitoring and reporting to the State under conditional full storage status. Staff met with AECOM, Expert Review Panel, State Dam Safety Branch, and Denver Water in August to review results from the Risk Analysis and discuss the development of monitoring thresholds. Staff is finalizing a framework for establishing and implementing the agreed upon thresholds. Staff has also developed plans for top dressing the crest of the embankment in 2017 and will submit the plans for State review.

3 Page 3 of 7 10/06/2016 Elkhead Reservoir Operations Below is a graph of recent Elkhead Reservoir Operations. April-July runoff into the reservoir was 91,400 acre-feet, or 125 percent of average. About 20 percent of this volume was released over the spillway due to the overwhelming rate of inflow. Releases from the 5000 acre-feet Recovery Program pool to benefit Native Fish in the Lower Yampa began August 17 th and will end October 10 th. The reservoir is currently 11 feet down from full pool storing 17,500 acre-feet (7200 acre-feet down from full). Maintenance Activities at Elkhead Reservoir Elkhead Outlet Works Repairs Recall the guides for the stems which raise and lower the outlet gates at Elkhead Dam need to be reinstalled with proper anchor bolts. The original contractor Ames used anchor bolts other than those provided by the gate manufacturer and the replacement bolts have had some pull out failures when the gates were operated last winter and spring.

4 Page 4 of 7 10/06/2016 When the stem guides (46-90 pound steel parts) are taken off the wall to install proper anchor bolts they should be sand blasted and repainted, as after 10 years they are showing some rust. In addition to the work on the stem guides the 42-inch fixed cone valve requires recoating of the carbon steel parts. This will require removing the valve from the outlet structure, disassembling it for sand blasting and painting, and reinstalling it. Before putting together a bid package with the assistance of AECOM our engineer we discussed the stem guide anchor bolt problem with Ames the original contractor. Ames has met with River District staff on site and is in the process of providing a quote for doing the recoating work in conjunction with anchor bolt replacement. Hopefully Ames and River District staff can reach an agreement on remedying the anchor bolt problem along with the necessary recoating work which is favorable. We expect to be able to report more at the Board meeting. Elkhead Spillway Fish Barrier Net Installation Pacific Netting Products (PNP) of Kingston, Washington installed the 600 foot long spillway fish barrier net and 800 foot long debris boom at Elkhead Reservoir September 19 th through the 30 th. The net and debris boom installation went very smoothly during some challenging weather days. PNP certainly showcased their expertise in the field of barrier nets and debris booms with this project. In spite of a lot of materials to assemble and taking up a good part of the boat ramp parking and one side of the boat ramp minimal disruption to recreational boating occurred. The net was fastened to micro pile anchors installed during the dam enlargement in 2006 and the debris boom was anchored using helical anchors screwed into the reservoir bottom slopes and 1000 pound Danforth anchors in the flat portions of the reservoir bottom. The net and debris boom project including materials, installation, engineering, and River District project management will be just about $1.3 million. The net should last at least 10 years and was constructed to allow for modular replacement of wearing panels. The debris boom should last 30 to 50 years. Colorado Parks and Wildlife which manage recreation and fishery issues at Elkhead will be responsible for cleaning and maintenance of the net and debris boom.

rope anchor line, and chain weighted bottom seal

5 Page 5 of 7 10/06/2016 The net with its wave guard and main cork lines, Dyneema mesh, chain and Dyneema rope anchor line, and chain weighted bottom seal skirt Elkhead Boat Ramp with debris boom assembly work area

debris skirt anchored to large concrete blocks cast in

6 Page 6 of 7 10/06/2016 Debris boom is constructed of foam filled 24-inch HDPE pipe and a 4-foot weighted debris skirt anchored to large concrete blocks cast in the bank well above water line 1000 pound debris boom anchor

7 Page 7 of 7 10/06/2016 Net installed and debris boom awaiting final anchorage adjustment The screened outlet tower and spillway barrier net will contain fish during releases and spills

CLAIBORNE LOCK AND DAM PERTINENT DATA

CLAIBORNE LOCK AND DAM PERTINENT DATA GENERAL Location Clarke, Monroe, & Wilcox Counties, Alabama; Alabama River, river mile 72.5 Drainage area Millers Ferry to Claiborne sq. mi. 836 Total drainage area