?2:231 . 4 STATE OF CALIFORNIA CALIFORNIA NATURAL RESOURCES AGENCY DEPARTMENT OF WATER RESOURCES DIVISION OF SAFETY OF DAMS INSPECTION OF DAM AND RESERVOIR IN CERTIFIED STATUS ?a Name of Dam New Bullards Bar Dam No. 1034 County Yuba Type of Darn Concrete arch Type of Spillway Gated ogee crest Water is 43.5 feet above spillway crest'and 19.7 feet below dam crest. Elevation 1945.3 feet Weather Conditions Overcast and cool, with rainfall later in the day Tim Troung, Justin Hoffman, Arnold Delema, Bill Zoellin, John Christensen, Christensen Contacts Made Associates, Inc; Marcus Williams, FERC Reason for Inspection Annual inspection Important Observations. Recommendations or Actions Taken . As discussed during the inspection follow up meeting, the foundation pressures, in Blocks 4, a new instrument/94 psi; in Block 8, a new instrument/50 psi; in Block 13, an old instrument/180 psi; and in Block 14, a new instrument/118 psi, have risen significantly since the rapid rise in the reservoir level. in addition, foundation extensometer data shows a small separation at the heel of the dam, up to about 0.79 mm in Block 13, since the reservoir began to fill. These issues and a potential seismic safety concern will be the subject of a technical briefing for DSOD and FERC to be held on June 10, 2016. . The foundation and formed drain cleaning contract is complete. Two plugged formed drains were found in Block 11. Flow has increased significantly at a few of the right gallery formed drains. However, the overall gallery seepage for a given reservoir elevation has been reduced since completion of the remedial grouting program. . The remedial grouting project final report should be submitted to DSOD for review and comment by June 30, 2016. The radial gate wire rope installation and testing program was successfully completed last October. - Vegetation clearing along the groins will be completed within 12 months, which is satisfactory. . On May 18, 2016, a DSOD engineer witnessed a partial travel test of the low level outlet valves. The penstock butterfly shutoff valve was also tested successfully. The system needs to be capable of running for an extended period of time at the restricted flow of 1250 cfs. Conclusions Based on the instrumentation data, and visual inspection, the dam, reservoir, and the appunenances are judged safe for interim use pending control of the increasing foundation uplift pressures and other work items listed above. Observations and Comments Da_m Overall views of the dam are shown in photographs 1 and 2. Conditions along the dam crest appeared to be unchanged from last year. Crack movement along the crest was normal in the 2015 data set, and nothing unusual was observed during the inspection. The latest quarterly data has not been formally received. The arch, thrust blocks, and adjoining abutments appeared to be stable and in satisfactory condition. No significantjoint offsets, cracks, or signs of thermal scaling, or other forms of visible concrete deterioration, were observed along the exterior faces of the dam. Of note, lift line seepage has appeared along the upper face since the recent reservoir rise, photographs1 and 3, for example. This is not a darn safety issue at this time. Inspected by WPennington {rig}? Photos taken? Yes No Date of Inspection 5/24/16 cc for Owner/ Book Date of Report 6/6/16 15 DWR 1261 (Rev. 10:09) Sheet 1 of INSPECTION ur- DAM AND RESERVOIR IN .. IED STATUS. Name ofDam New Bullards Bar Dam No 1034 Date of Inspection 5/24/16 Observations and Comments Sgillway No rodent activity was observed in the immediate vicinity of the groins or abutments. Vegetation removal along the groins is scheduled within twelve months, which is acceptable to DSOD, photograph 4. A minimum three year clearing cycle is recommended. The left gallery was traversed from the upper access to the bottom ofthe gallery. No indications of unusual stress or movement were observed. The gallery concrete remains in satisfactory condition. The foundation edit at Elevation 1387.5 was not pumped down adequately for complete access. To the extent visible, conditions appeared to be normal. The owner has installed a few drain hole sand traps in the galleries, as for example, in Block 13, photograph 5. The sand accumulation was not significant at this location. The right gallery was traversed from the upper access door to the sump area. Conditions appeared to be about the same as last year, except for the seepage, which is discussed in the Seepage paragraphs. Drain hole sand traps were also installed at a few locations in the right gallery. The only trap with much sand was in Block 10, at Elevation 1527.5, where about 1 cup of sand was observed. It appears that the sand accumulation has subsided to a large degree since the remedial grouting program was completed. Conditions within the upper instrument gallery and utility bypass gallery were normal. The concrete remains in good condition and no signs of unusual stress were noted. Areas of standing water were observed. Most of the water originates from drilled drains that daylight in the crown of the gaHenes. Exploration adit TR2 at Block 8 and exploration adit TR1at Block 13 appeared to be unchanged and in satisfactory condition. Hydrogen sulfide gas levels above the allowable limit were not detected in this year. The light seepage and standing water noted in the explorations tunnels was typical of previous inspections. The ogee crest and spillway chute were observed from the crest roadway, hoist deck, and left pier, and from across the canyon. The walls and chute floor remain in satisfactory condition. No signs of misalignment, settlement, or buckling were observed. Some of the sealed cracks along the chute floor are visible in photograph 6. The concrete abutments and piers forming the radial gate structure remain stable, aligned, and in satisfactory condition. The radial gate hoist decks and bridge decks were also in satisfactory condition, photograph 7. The radial gates were observed from the hoist decks, bridge decks, and from the left training wall. No signs of overstress or misalignment of the members were observed. As in the past, the paint coatings and the visible bolted and welded connections appeared to be in good condition, photographs 8 and 9, for example. Regular debris removal along the members should continue for corrosion control and inspection purposes. The wire ropes were replaced last year and successfully tested in October 2015. DWR1251(rev.10f09) Sheet 2 of 15 INSPECTION VI: DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 5/24/16 Observations and Comments Outlet Seepage Instr. The low level outlet passes thru the central portion of the dam. It was not in operation at the time of the inspection. A trash rack, bulkhead system, and gantry crane are located at the upstream side of the dam. The discharge is controlled by a 72?inch butterfly guard valve located just upstream from the 72-inch diameter hollowjet discharge valve. See photograph 10. Both valves were successfully tested through partial travel for a DSOD engineer on May 18, 2016. DSOD requires that the outlet system be capable of lowering the hydraulic head by 10 percent in 10 days, which is about 63 feet. FERC has restricted the discharge to a maximum of 1250 due to vibration at higher flow. This is insufficient to meet the drawdown requirement. However, the spillway gates can lower the hydraulic head by about 53 feet. In addition, the 15-foot diameter power penstock on the right abutment can release 14? feet of head relative to the normal maximum water surface. The combined discharge capacity from all sources is considered sufficient. However, the ability to release a safe and sustained discharge of 1250 is considered necessary. Lift line seepage was visible along the upper portion of the face. This is attributed to the reservoir rise and resultant change in the shape of the arch. A small, but persistent seep, noted in recent years on the lower left face of the dam, was flowing at perhaps 1-2 gpm. This is about the same as in recent years. The left Gallery was relatively dry, with a slow, and small, gain in seepage as we walked down to block 16. The long standing diagonal crack in the crown of the left thrust block stairwell was running several This' Is not that unusual when the reservoir is high. However, the location should be monitored for unexpected changes In seasonal flow. The right gallery seepage flow is much reduced for a given reservoir level since completion of the recent foundation grouting program. Most of the seepage begins at Block 8 where a significant portion of the flow is from wall formed drains. Seepage continued to increase into blocks 9 and 10, which was expected. Note that in block 11, between two blocked formed drains B11-6 and 811-7, a lift joint was squirting water into the gallery, photograph 11. The drain cleaning contractor may not have been able to clear the formed drains with the equipment on hand. The significance of the lift line seepage at this location is that the upstream face may be opening up due the increased reservoir head. It looked like the lift line and surrounding concrete had been cleaned of calcite during the drain cleaning contract. This may have facilitated the emergence of seepage that was not observed in the past. DSOD receives a DSSIVIR from the owner on a quarterly basis. However, the first quarter 2016 report has not been received formally. This data is the most relevant to the current foundation conditions, as nothing unusual was observed in the fourth quarter 2015 data. The following data is normally collected and will be reviewed in detail when the written copy of the report arrives: . Stress, strain, and joint meters - read on five-year cycle, but not processed and not needed at this time. Foundation deformation meters read annually near maximum reservoir level. Crack monitors They are normally read during the second and fourth quarters. Thermometers read quarterly. DWR 1261 (rev. 10r09) Sheet 3 of 15 INSPECTION ul: DAM AND RESERVOIR IN ..-IED STATUS Name of Dam New Bullards Bar - Dam No. 1034 Date of inspection 5/24/16 Observations and Comments DWR 1261 (rev. 10f09) Seepage weirs read weekly. Uplift pressure meters measured weekly. Survey targets on dam face read annually near maximum reservoir level. Plumb lines measured quarterly. Foundation extensometers Long term reading schedule to be determined. Sheet 4 of 15 INSPECTION uF DAM AND RESERVOIR IN STATUS Date of inspection 5/24/16 i Name ofDam New Bullards Bar Dam No. 1034 i 1. The spillway at right, and power penstock, at left center, are shown in this View of the dam. The vertical dark streaks within the oval are active lift line seepage areas. Sheet 5 of 15 INSPECTION uF DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 5/24/16 2. This View of the dam shows the penstock intake crane, crest road, and the spillway. I I DWR1261(rev.10f09) Sheet 6 of 15 INSPECTION uF DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam Na 1034 Date of Inspection 5/24/16 ?which .- HIThis view along the right side of the dam shows active lift line seepage that has developed since the relatively fast rise of the reservoir this season. The power penstock is directly below the dashed oval. DWR1261(rev.10l09) Sheet 7 - of 15 INSPECTION uF DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam N0. 1034 Date of Inspection 5/24/16 4. The vegetation along the grains will be cleared within twelve months. The limits of required clearing were discussed in the field. DWR 1261 (rev. 10mg) Sheet 8 0f 15 INSPECTION 'uF DAM AND RESERVOIR IN .r'lED STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 5/24/16 5. This is a sand trap attached to a drain hole in the left foundation gallery near formed drain B13-7. This was done to get an indication of the amount of sand that is entering the galleries in recent years. In this case, the amount of sand was insignificant. Only one trap in Block 10 had much sand, about 1 cup full. The pressure gage is visible on the right side of the pipe. An electronic flow and total volume recorder is also visible. DWR1261(rev.10109) Sheet 9 of 15 uF DAM AND RESERVOIR IN u-?lED STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 5/24/16 6. This View looking along the spillway shows minor seepage passing by the gate seals and two of the several sealed cracks in the chute floor, arrows. The chute could not be walked due to the safety hazards. The chute walls remain stable and in satisfactory condition. Sheet 10 of 15 INSPECTION UF DAM AND RESERVOIR IN IFIED STATUS Name of Dam New Bullards Bar Dam Na 1034 Date of Inspection 5/24/16 7. The radial gate hoist decks and equipment appeared to be well maintained. The control house is a right center. DWR1261(rev.10l09) Sheet 11 of 15 INSPECTION uF DAM AND RESERVOIR IN STATUS Name ofDam New Bullards Bar Dam No. 1034 Date of Inspection 5/24/'21The radial gates appeared to be in satisfactory condition, as shown in this View of the left gate. The coatings and connections at each gate looked good from the limited vantage points. DWR1261(rev.10i09) Sheet 12 of 15 INSPECTION UF DAM AND RESERVOIR IN CERII STATUS Name of Dam New Bullards Bar Darn No. 1034 Date of Inspection 5/24/16 9. The portion of the radial arms and the trunnions at the right gate are shown. No signs of overstress or misalignment of the members were observed at any of the gates. A little bit of the moss has dropped onto the trunnion from the left pier. Debris should be kept clear of the gate members and trunnions, as has been done in the past. DWR1261 (rev. 10r09) Sheet 13 of INSPECTION uF DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 5/24/16 11. This view is looking generally and at the upstream side of the right foundation gallery, Block 10. Seepage can be seen squirting from the lift line below the double arrow. The formed drains on either side were fully blocked. The roughened concrete above and below the lift line may indicate that calcite was removed from this area during the drain cleaning project, thus facilitating the seepage where none was observed in recent years. The flow may be an indication that the lift lines along the upstream side of the dam are opening up as the dam arches in response to the reservoir rise. DWR1261(rev.10l09} Sheet 15 of 15 STATE OF CALIFORNIA 'i "i CALIFORNIA NATURAL RESOURCES AGENCY . DEPARTMENT OF WATER RESOURCES Cr:- DIVISION OF SAFETY OF DAMS INSPECTION OF DAM AND RESERVOIR IN CERTIFIED STATUS Name of Dam New Bullards Bar Dam No. 1034 County Yuba Type of Dam Variable Radius Arch Type of Spiliway Gated ogee crest Water is 36.0 feet above spillway crest and 27.0 feet below darn crest. Water surface was at Elevation 1 938.0 feet. Weather Conditions Clear skies, about 64 Contacts Made Tim Truong Chief Dam Safety Engineer with Yuba County Water Agency. Reason for Inspection Valve operations - Penstock and low level outlet. Important Observations. Recommendations or Actions Taken - The valves performed well. - Due to excessive vibration at high flows, FERC has limited the maximum allowable low level outlet release to 12500fs. During the next scheduled low level outlet operation, the outlet should be opened to this flow. Conclusions The 180-inch penstock butterfly valve and the tandem low level outlet valves (84-inch butterfly valve and 72- inch hollowjet valve) were operated satisfactorily. Observations and Comments Valve I arrived at the boat dock parking lot at 8:00am and met Tim Truong. We then proceeded to Operations the penstock control facilities located on the right abutment of the dam. The 180- inch penstock butterfly valve performed well when it was fully cycled three times during the inspection. The valve took about 31 seconds to Close and about 3 minutes and 40 seconds to open. The penstock valve was cycled with the local controls and with offsite controls located at the Colgate Power House. The valve Operation was tested under normal and trip (transfer and excess flow) conditions. We then proceeded to the low level outlet works control facility located at the toe of the dam. The Operating procedure consisted of fully opening the 84-inch butterfly valve and then Opening the 72-inch hollowjet valve to a 7% open position. The shutdown procedure consisted of fully Closing the hollow jet valve and then fully Closing the butterfly valve. Both valves performed well during the inspection. During the test, the hollowjet valve did not oscillate, and no unusual noises were heard. The operating cycle times were not recorded. I left the site at 10:30am. Mme/? Inspected by Alan Van Matre Photos taken? YES No Date of Inspection 5/18/16 a, If} CC for Owner/Book Date of Report 5/23/2016 [p 7? 1' DWR 1261 (Rev. 10i09) Sheet 1 ofw 2 STATE OF CALIFORNIA 'i "i CALIFORNIA NATURAL RESOURCES AGENCY . DEPARTMENT OF WATER RESOURCES Cr:- DIVISION OF SAFETY OF DAMS INSPECTION OF DAM AND RESERVOIR IN CERTIFIED STATUS Name of Dam New Bullards Bar Dam No. 1034 County Yuba Type of Dam Variable Radius Arch Type of Spiliway Gated ogee crest Water is 36.0 feet above spillway crest and 27.0 feet below darn crest. Water surface was at Elevation 1 938.0 feet. Weather Conditions Clear skies, about 64 Contacts Made Tim Truong Chief Dam Safety Engineer with Yuba County Water Agency. Reason for Inspection Valve operations - Penstock and low level outlet. Important Observations. Recommendations or Actions Taken - The valves performed well. - Due to excessive vibration at high flows, FERC has limited the maximum allowable low level outlet release to 12500fs. During the next scheduled low level outlet operation, the outlet should be opened to this flow. Conclusions The 180-inch penstock butterfly valve and the tandem low level outlet valves (84-inch butterfly valve and 72- inch hollowjet valve) were operated satisfactorily. Observations and Comments Valve I arrived at the boat dock parking lot at 8:00am and met Tim Truong. We then proceeded to Operations the penstock control facilities located on the right abutment of the dam. The 180- inch penstock butterfly valve performed well when it was fully cycled three times during the inspection. The valve took about 31 seconds to Close and about 3 minutes and 40 seconds to open. The penstock valve was cycled with the local controls and with offsite controls located at the Colgate Power House. The valve Operation was tested under normal and trip (transfer and excess flow) conditions. We then proceeded to the low level outlet works control facility located at the toe of the dam. The Operating procedure consisted of fully opening the 84-inch butterfly valve and then Opening the 72-inch hollowjet valve to a 7% open position. The shutdown procedure consisted of fully Closing the hollow jet valve and then fully Closing the butterfly valve. Both valves performed well during the inspection. During the test, the hollowjet valve did not oscillate, and no unusual noises were heard. The operating cycle times were not recorded. I left the site at 10:30am. Mme/? Inspected by Alan Van Matre Photos taken? YES No Date of Inspection 5/18/16 a, If} CC for Owner/Book Date of Report 5/23/2016 [p 7? 1' DWR 1261 (Rev. 10i09) Sheet 1 ofw 2 /e STATE OF CALIFORNIA CALIFORNIA NATURAL RESOURCES AGENCY DEPARTMENT OF WATER RESOURCES DIVISION OF SAFETY OF DAMS INSPECTION OF DAM AND RESERVOIR IN CERTIFIED STATUS Name of Dam New Bullards Bar Darn No. 1034 County Yuba Type of Dam Concrete arch Type of Spillway Gated ogee crest Water is 46 feet below spillway crest and 109 feet below dam crest. Elevation ~1856 feet Weather Conditions Sunny and warm Contacts Made Peter Wade, Vinh Tran, FERC Reason for Inspection Annual Inspection Important Observations, Recommendations or Actions Taken . The original radial gate wire ropes are scheduled for replacement this September, to be followed by tension and balance tests in October. a A vegetation control plan for the groins should be submitted to DSOD for review and comment. A three year cycle is recommended. . Gallery seepage has been reduced since the remedial grouting program, except in Block 8 on the right abutment, where the seepage remains above the long term trend line. 0 The owner has initiated a foundation drain and formed drain cleaning program. The program is currently on hold due to outside circumstances affecting the contractor, but is expected to resume soon. 0 Consideration should be given to measures that would mitigate the potential hazard posed by the location of the gantry crane footings relative to the crest roadway surface. Conclusions Based on the instrumentation data, and visual inspection, the dam, reservoir, and the appurtenances are judged safe for continued use pending completion of the drain cleaning program and a longer term gallery seepage control program.- Observations and Comments Dam No signs of unusual stress were noted along the dam crest. See photographs 1 and 2, for example. The transverse cracks and joints along the crest appeared to be normal. While examining the power intake gantry crane, we noted the location of the crane footings relative to the crest roadway. These footings could pose a traffic hazard as well as take the crane out of service for an extended period of time, should an impact occur. Consideration should be given to measures that would mitigate the hazard. The arch, thrust blocks, and adjoining abutments appeared to be stable and in satisfactory condition. No significantjoint offsets, cracks, or signs of thermal scaling were observed along the exterior faces of the dam, photographs 3, 4, and 5. Rodth control is always good at this facility. In general, vegetation control has been good. However, seepage monitoring along the groins is becoming progressively more difficult due to the maturing vegetation. A vegetation control plan should be developed and provided to DSOD for review and comment. A three year clearing cycle is recommended. The left gallery was traversed from the upper access door to the sump. No indications of unusual stress or movement were observed. We walked the upper instrument gallery at elevation 1642.5 feet. Conditions were normal. Gallery seepage of any significance started about half way along inspected by WPennington al 6 Photos taken? Yes No Date of Inspection 6/2/15 I I _0 cc for Owner/Book Date of Report 6/9/15 u" I own 1261 (Rev. totes) Sheet 1 of 7 in (5/0 t; LIL r/t/ INSPECTION Or DAM AND RESERVOIR IN CERTII-IED STATUS Name ofDam New Bullards Bar Dam No. 1034 Date of Inspection 6/2/15 Observations and Comments Spillway Outlet Seepage Block 20. The foundation adit at Elevation 1387.5 was not pumped down for access. The right gallery was traversed from the upper access door to the sump. No indications of unusual stress or movement were observed. Conditions within the bypass gallery were normal for as far as we could walk, which was perhaps half way. The gas sensor alerted us to an oxygen level below 19.5 percent. We retreated the way we came in. Long stretches of the gallery had water on the floor due to the recent drain cleaning effort. Exploration tunnel TR2 at Elevation 1575 feet and exploration tunnel TR1at Elevation 1402.5 appeared to be unchanged and in satisfactory condition. We left TR-1 after the gas meter detected hydrogen sulfide gas above the allowable limit. The light seepage and standing water noted in the exploration was typical of previous inspections. The ogee crest and spillway chute were not reviewed in detail. This will be done in September 2015, when the original radial gate hoist ropes are replaced. A wire rope tension and balancing test is tentatively scheduled for October 2015. The gate hoist decks and the bridge decks appeared to be in satisfactory condition, photograph 2, for example. The radial gates were observed from the bridge decks, and from the left outside training wall. They will be examined in more detail during the upcoming wire rope replacement project. No signs of overstress or misalignment of the members were observed. The paint coatings and the visible bolted and welded connections appeared to be in good condition, photograph 6. Regular debris removal should continue for corrosion control and inspection purposes, photograph 6. The low level outlet passes thru the central portion of the dam. it was not in operation at the time of the inspection. A trash rack, bulkhead system, and gantry crane are located at the upstream side of the dam. The discharge is controlled by a 72-inch butterfly guard valve located just upstream from the 72-inch diameter hollowjet discharge valve. See photograph 7. The outlet butterfly guard valve and hollowjet discharge valve was successfully tested for DSOD in March 2015. The guard valve was fully cycled and the discharge valve was partially cycled. DSOD requires that the outlet system be capable of lowering the hydraulic head by 10 percent in 10 days, which is about 63 feet. The valve is restricted to a maximum discharge of 1250 cfs, which is insufficient to meet the drawdown requirement. However, the spillway gates can lower the hydraulic head by about 53 feet. In addition, the 15-foot diameter power penstock on the right abutment can release 147 feet of head relative to the normal maximum water surface. The combined discharge capacity from all sources is considered sufficient. Seepage conditions along the face of the dam and the abutments appeared to be normal. A small, persistent seep, seen in recent years on the lower left face of the dam, was flowing 1-2 gpm. The owner is attempting to determine the flow path and decide if mitigation measures are needed. The gallery seepage was relatively low during the inspection. Overall, the seepage has decreased markedly since remedial foundation grouting was completed more than a year ago, even when accounting for the low reservoir level. The exception is within Block 8 of the right abutment, where recent seepage flow is somewhat above the long term trend line. Seepage in the left gallery has ranged from somewhat above to somewhat below the long term trend line. Before any further Sheet 2 of 7 INSPECTION DAM AND RESERVOIR IN CERTII-IED STATUS Name of Dam New Bullards Bar Dam N0 1034 Date of Inspection 612/1 5 Observations and Comments remedial grouting is attempted, it will be necessary to monitor the seepage during high reservoir conditions. The owner has initiated a foundation drain and formed drain cleaning program. This effort is on hold due to outside circumstances affecting the contractor, but is expected to resume soon. An increase is drainage flow may result, which may cloud a determination about the effectiveness of the remedial grouting program. The gallery beneath the spillway had a small amount of seepage along cracks, but far less than under full head conditions, or during winter storms. Instr. DSOD receives a from the owner on a quarterly basis. The most recent is for the first quarter of 2015. The quarterly data is an interim product. The following comments are provided: - Stress, strain, and joint meters read on five?year cycle, ?but not processed and not needed at this time. . Foundation deformation meters read annually near maximum reservoir level. Not read during the latest quarter. . Crack monitors Not read during latest quarter. They are normally read during the second and fourth quarters. . . Thermometers read quarterly. Temperature distribution and values were normal. . Seepage weirs read weekly. See seepage discussion above. Uplift pressure meters measured weekly. Data remains normal. The meters installed during the remedial grouting program show low values of uplift, but they have not seen a full reservoir head. . Survey targets on darn face read annually near maximum reservoir level. Not surveyed during latest quarter. . Plumb lines measured quarterly. Data remains normal. The dam continues to respond elastically to the changes in lake level and environmental conditions. . Foundation extensometers These new instruments were installed by last January. The initial readings will be provided in the annual Sheet 3 of 7 INSPECTION OI- DAM AND RESERVOIR IN CERTIFIED STATUS Name ofDam New Bullards Bar Dam No. 1034 Date of Inspection 6/2/15 1. The crest road remains in good condition, and appeared to be essentially unchanged from the last inspection. The gantry crane is visible in this View looking towards the right abutment. The unprotected crane footings pose a potential impact hazard. in 4. 2. This View of the dam crest also shows the spillway bridge and the radial gate hoist equipment. These features appeared to be in satisfactory condition. DWR 1261 (rev. 10109) Sheet 4 0f 7 INSPECTION Or' DAM AND RESERVOIR IN CERTIHED STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6/2/1 5 4. Conditions also appeared to be normal along the left side of the dam and abutment. DWR 1261 (rev. 10109) Sheet 5 of INSPECTION OI- DAM AND RESERVOIR IN CERTII-IED STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6/2/15 5. This View looking towards the left abutment shows typical normal conditions along the upstream side of the dam. 6. The radial gates remain in satisfactory condition. However, the debris along the gate ribs combines with water and animal waste to create a corrosive environment. Cleaning of these areas should continue on a regular schedule. DWR 1261 (rev. 10109) Sheet 6 0f STATE OF CALIFORNIA ?t a Vq' CALIFORNIA NATURAL RESOURCES AGENCY v.29. DEPARTMENT OF WATER RESOURCES DIVISION OF SAFETY OF DAMS INSPECTION OF DAM AND RESERVOIR IN CERTIFIED STATUS Name of Darn New Bullards Bar Dam No. 1034 County Yuba Type of Dam Variable Radius Arch Type of Spillway Gated ogee crest Water is 33.87 feet below spillway crest and 97.87 feet below dam crest. Water surface was at Elevation 1 868.13 feet. Weather Conditions Decent morning weather, about 68 Contacts Made Peter Wade Yuba County Water Agency. Reason for Inspection Valve operations - Penstock and low level outlet. Important Observations. Recommendations or Actions Taken The valves performed well. Conclusions The ?ISO-inch penstock butterfly valve and the tandem low level outlet valves (84-inch butterfly valve and 72- inch hollowjet valve) were all in a dependable operating condition. Observations and Comments Valve I arrived on site at 9:00am at the onsite penstock control facilities located on the right Operations abutment of the dam. The 180-inch penstock butterfly valve performed well when it was fully cycled three times during the inspection. The valve was cycled with the local controls and with offsite controls located at the Colgate Power House. The valve operation was tested under normal and trip (transfer and excess flow) conditions. The valve took about 1 minute and 37 seconds to close and about 3 minutes and 38 seconds to open. We then proceeded to the low level outlet works control facility located at the toe of the dam. The low level outlet valves operating procedure consisted of fully opening the 84? inch butterfly valve and then opening the tandem 72?inch hollowjet valve to a 7% open position. The shutdown procedure consisted of fully closing the hollowjet valve and then fully closing the butterfly valve. Both valves performed well during the inspection. The hollow jet valve normally oscillates when opened more than 10%, which is a longstanding condition. The hollow jet valve did not oscillate, and no unusual noises were heard during this inspection. The operating cycle times were not recorded. I left the site at 11:30am. aw/ Inspected by Alan Van Ma?tre? Photos taken? Yes No Date of Inspection 3/19/15 cc for Owner/Book Date of Report DWR 1261 (Rev. 10109) Sheet STATE OF CALIFORNIA I /e .LIFORNIA NATURAL RESOURCES AGENCY DEPARTMENT OF WATER RESOURCES DIVISION OF SAFETY OF DAMS INSPECTION OF DAM AND RESERVOIR IN CERTIFIED STATUS Name of Dam New Bullards Bar Dam No. 1034 County Yuba Type of Dam Concrete arch Type ofSpillway Gated ogee crest Water is 79 feet below spillway crest and 142 feet below dam crest. Elevation ~1823 Weather Conditions Sunny and mild Contacts Made Mike Kline and Peter Wade, Vinh Tran, and the FERC Part 12 consultants Reason for Inspection Annual inspection Important Observations. Recommendations or Actions Taken a This inspection was conducted jointly with the FERC Part 12 inspection team. The independent Consultants are Steve Verigin, and Bill Rettberg. Consultants Bill Cole, Carol Buckles, and Yusof Ghanaat participated in support of the Independent Consultants. . The owner should ensure that the new instrumentation program is fully functional before the reservoir starts to rise this winter. Conclusions From the known information and visual inspection, the dam, reservoir, and the appurtenances are judged safe for continued use pending completion ofthe new instrument installations and completion of the longer term program to control foundation seepage in the galleries. Observations and Comments Da_m No signs of unusual stress were noted along the darn crest. See photographs 1 and 2, for example. The transverse cracks and joints along the crest appeared to be normal, and the crack sealant remains intact, where it has been applied. No significantjoint offsets, cracks, or signs of thermal scaling were observed along the faces of the dam, photographs 3 through 7. The thrust blocks and adjoining abutments appeared to be stable and in satisfactory condition. Rodent control is not an issue at this dam. The vegetation along the left groin should be cleared over the next two seasons to allow a better view for inspections and seepage monitoring. The right gallery was traversed from the upper access door to the sump. No indications of unusual stress or movement were observed. Conditions within the bypass gallery were normal and satisfactory. A minor amount of seepage was observed. This is typical. Exploration tunnel TR2 at Elevation 1575 feet and exploration tunnel TR1at Elevation 1402.5 appeared to be unchanged and in satisfactory condition. The light seepage and standing water noted were typical of previous inspections. The left gallery was traversed from the upper access door to the sump. No indications of unusual stress or movement were observed. The edit at Elevation 1387.5 was pumped down, but the lowest portion could not be entered due to a potentially unsafe atmosphere. Spillway The ogee crest and discharge chute remain in satisfactory condition. See photographs 3, and 9 through 13. The concrete hoist decks and bridge decks appeared to be in satisfactory condition as well. Since the inspection, minor cracking along the chute floor has been repaired. The owner should continue to monitor the chute floor following significant spillway releases or earthquakes. Inspected by WPennIthon I 4' Photos taken? Yes No Date of Inspection 8/25/14 fl jig/?1 I CC for Owner/Book Date of Report 10/7/14 I I Sheet 4 01? Vol) [ya/I INSPECTION Ol- JAM AND RESERVOIR IN CERTIF. STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 8/25/14 Observations and Comments Outlet Seepage The radial gates were lifted about 4?feet during the inspection, photographs 3 and 9. The operating equipment appeared to be well maintained. The radial gates were observed from the approach apron, from the bridge decks, and from the left outside training wall. The coatings remain in good condition. The visible bolted and welded connections appeared to be in good condition, photograph 10, for example. No signs of overstress or misalignment of the gate members were observed. The wire ropes appeared to be well maintained, but are original, photographs 12 and 13. Regular debris removal along the radial gate members is a cumbersome operation, but this process should continue for corrosion control and inspection purposes. The low level outlet passes thru the central portion of the dam. It was not in operation at the time of the inspection. A trash rack, bulkhead system. and gantry crane are located at the upstream side of the dam. The discharge is controlled by a 72-inch butterfly guard valve located just upstream from the 72-inch diameter hollow jet discharge valve. See photograph 14. The outlet valve was successfully tested for DSOD in November 2011. DSOD requires that the outlet system be capable of lowering the hydraulic head by 10 percent in 10 days, which is about 63 feet. The valve is restricted to a maximum discharge of1250 cfs, which is insufficient to meet the drawdown requirement. However, the spillway gates can lower the hydraulic head by about 53 feet. In addition, the 15-foot diameter power penstock on the right abutment can release 147' feet of head relative to the normal maximum water surface. The combined discharge capacity from all sources is considered sufficient. Seepage conditions along the face of the dam and the abutments appeared to be normal, except for a persistent seep on the lower left face, photographs 6 and 7, which appeared to be flowing more than during recent inspections, even with the very low reservoir level. An attempt should be made to determine the flow path and determine if repairs are necessary. The recent remedial grouting in Block 13 of the right gallery has markedly decreased the drainage, photograph 8, even after accounting for the low reservoir level. The owner will carefully monitor the seepage conditions as the reservoir level goes up this winter. Seepage in the left gallery appeared to be about normal for the reservoir level. The gallery beneath the spillway had a small amount of seepage along cracks, but far less than under full head conditions, or during winter storms. The instrumentation program is being revised in conjunction with the remedial foundation grouting program. Foundation extensometer casings have set and the instruments will be installed by the end of 2014. Additional uplift monitoring instruments have also been installed. The response of the dam and foundation will be monitored carefully as the reservoir rises this winter. Normally a is sent to DSOD on a quarterly basis. The reports have been delayed because of changes to the monitoring program. Up to date information is expected before the end of October 2014. The last submitted was for the first quarter of 2014. The data reflects some benefit from the remedial grouting in Block13, and some temporary variation in the uplift pressures. The data indicates that the dam was performing satisfactorily. I Sheet 2 of 14 INSPECTION OF HAM AND RESERVOIR IN STATUS Name of Dam New Buliards Bar Dam No. 1034 Date of Inspection 8/25/14 Observations and Comments Based on my field inspection, my review of the available monitoring data, and my discussions with the owner's representatives, the dam remains in satisfactory condition for continued use pending completion ofthe instrument package and any additional remedial grouting that may be needed. DWR1261(rev.10109) Sheet 3 of 14 INSPECTION OF 4AM AND RESERVOIR IN CERTIFLJ STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 8/25/14 1. The gantry crane is Visible in this View of the crest road. The road remains in good condition, and appeared to be essentially unchanged from the last inspection. 2. This View of the dam crest also shows the spillway bridge and the radial gate hoist deck. The bridge appeared to be in satisfactory condition. DWR 1261 (rev. 10109) Sheet 4 0f 14 INSPECTION OF HAM AND RESERVOIR IN CERTIFIEJ STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 8/25/14 3. The radial gates are Visible in this View from the left abutment. No signs of distress or signi?cant concrete deterioration were observed. 4. The gantry system for the power penstock is Visible in this View of the darn taken from the right abutment. Sheet 5 of 14 INSPECTION OF HAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 8/25/14 5. The right groin is shown in this View from the lower parking area. Conditions appeared to be normal. DWR1261(rev.10i09) Sheet 6 of i INSPECTION OF HAM AND RESERVOIR IN CERTIFILJ STATUS Name ofDam New Bullards Bar Dam No. 1034 Date of Inspection 8/25/14 . l? I 6. This View along the left face and groin also shows a seep, arrow, that appears to have increased in ?ow since the last inspection. The ?ow may have doubled. Sheet 7 of 14 INSPECTION OF HAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 8/25/14 7. The central part of the face is shown. The power penstock exits the dam on the right abutment, arrow. The seep shown in photograph 6 is at the dashed arrow. Sheet 8 of 14 INSPECTION OF .JAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 8/25/14 I I ML It 8. Total seepage at the toe of the right gallery stairwell, Block 13, is shown. The seepage is much reduced following the remedial grouting in Block 13, even when taking into account the low reservoir level. This is clear from the submitted right abutment seepage data. The ?ow will be watched closely to see if the seepage is reduced at higher reservoir levels. DWR1261(rev.10f09) Sheet 9 of 14 INSPECTION OF AND RESERVOIR IN STATUS Name of Darn New Bullards Bar Dam No. 1034 Date of Inspection 8/25/14 9. The spillway gates are open about 4~feet in this cross canyon View. Gate operation was satisfactory during the partial travel test that occurred earlier in the day. Sheet 10 of 14 INSPECTION OF HAM AND RESERVOIR IN STATUS Name of Dam New Bar Dam No. 1034 Date of Inspection 8/25/14 10. The spillway chute remains in satisfactory condition. No signs of overstress or instability were observed. Minor crack repairs were completed recently. The cracking across the chute panels should be monitored after signi?cant earthquakes or spills. DWR1261 (rev. 10109) Sheet 11 of 14 INSPECTION OF HAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 8/25/14 11. This View is looking down at the left radial gate. The coatings, connections and member alignment appeared to be satisfactory. Sheet 12 of 14 INSPECTION OF HAM AND RESERVOIR IN CERTIFIFJ STATUS Name of Dam New Bullards Bar Darn No. 1034 Date of Inspection 8/25/14 13. A typical wire rope connection to the radial gate leaf is shown. Sheet 13 of i STATE OF . CALIFORNIA NATURAL RESOURCES AGENCY i DEPARTMENT OF WATER RESOURCES DIVISION OF SAFETY OF DAMS INSPECTION OF DAM AND RESERVOIR IN CERTIFIED STATUS Name of Dam New Bullards Bar Dam No. 1034 County Yuba Type of Dam Concrete arch Type of Spiilway Gated ogee weir Water is 96 feet below the Max. storage level of 1956 ft., 105 feet below the dam crest. Weather . . . Conditions Clear and warm during the inspection Mike Kline, YCWA Power Systems Manager; Peter Wade, YCWA Engineer; Dan Cardoza, YCWA Plane Mechanic; Tom Foss, YCWA Electrical Supervisor; Arnold Delima, YCWA Contacts Made Operations Supervisor; Travis Ford, HDR Engineer; Chris Buller, HDR Engineer. Reason for Inspection Full travel test of the three radial gates and evaluation of the spillway gate lift cables. Important Observations, Recommendations or Actions Taken I observed a successful full travel test of the three radial gates. The reservoir elevation was 1860-feet, which is well below the elevation of the spillway sill. The owner hired HDR to inspect and evaluate the spillway gate wire rope lift cables. Each gate is lifted with two sets of six cables attached to the lower corners of the gates using guide blocks working through a pin with bolt connections. The cables are reportedly original to the dam and therefore more than forty years old. While the condition of the cables is surprising good considering their age, limited and localized areas of high wear are evident, and it appears the cables have reached the end of their useful life. USACE Engineering Manual EM 1110-2-3200, dated 30 September 1998, recommends that wire rope used on gate-operating devices be assumed to have a maximum service life of 20 years. With the actual service life extended to more than twice the recommended time, prudence dictates that cables should be repiaced as soon as it reasonably possible for the owner to do so. The right gate showed 1-inch of rack with the right side higher, the center gate showed 1/4-inch of rack with the left side higher, and the left gate showed 1/2?inch of rack with the left side higher. Misalignment in the form of rack can create very high loads throughout the gate structure and lifting mechanism. The tension and adjustment of all lift cables should be adjusted to minimize or eliminate the rack measured. Based on the strain on the motor and transmission observed during inspection, the Volkswagen drive motor and transmission used to lift the center gate in an emergency appears to be inadequate for the task and should be replaced with a more robust unit. Conclusions From the known information and visual inspection, the dam, reservoir, and the appurtenances are judged safe for continued use. Observations and Comments Spillway The owner performed a full travel test on all three gates using four separate power sources. The electrically driven gate motors were powered by 1) mini-hydro plant at the base of the dam, 2) line power, and, 3) a portable 45kW generator. Power to the gate motors is delivered at 208 volts, starting amperage is on the order of 57 amps or so, and running amperage was on the order of 17 to 20 amps. Tom Foss indicated those vaiues were normal, and that everything was working as it should be, but the December 14, 2007 report noted that, ?an electrical load test Inspected by J. Lowe 5' Photos taken? Yes N0 Date of inspection 6 September 2013 1 cc for Owner/Book Date of Report 9 September I I I, DWR 1261 (Rev. 10109) Sheet 1 of 10 1417571 ?ow? INSPECTION DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar . Dam No. 1034 Date of Inspection 6 September 2013 Observations and Comments indicated that about 5 percent more current was needed to iift the gate compared to last year", attributing this increase, at least in part, to cold weather. Based on Mr. Foss? report of the system performance it appears we did not experience increased or unusual loads during these tests. in addition to the three electrical power sources a 1968 vintage Volkswagen (VW) motor can be used to lift the center gate through a direct drive transmission in an emergency. It appears this motor was derived, if not taken directiy from, a common VW automobile motor. Whiie the VW motor successfully moved the center gate a distance of one foot both up and down, I doubt that the ancient air cooied motor would survive the strain of lifting the gate throughout its full height. Based on the strain on the motor and transmission observed during inspection, the Volkswagen drive motor and transmission used to iift the center gate in an emergency appears to be inadequate for the task and should be replaced with a more robust unit. Before the testing began, the operators opened permanently mounted fixed position spray nozzles to iubricate the gate seals. Each ofthe three gates were fully opened and closed, beginning with the right gate and ending with the left. Full gate opening is a little more than 45 feet. Full lift and drop takes about two hours per gate. Stopping for measurements, inspection, and maintenance adds significantly to the time required, and so fully testing all three gates can be a 12-hour proposition. Gates were temporarily held at the roughly two foot lift point while HDR Engineer, Travis Ford, measured rack. The right gate showed 1-inch of rack with the right side higher, the center gate showed 1/4-inch of rack with the left side higher, and the ieft gate showed 1/2?inch of rack with the left side higher. Misalignment in the form of rack can create very high loads throughout the gate structure and lifting mechanism. The tension and adjustment of all lift cables should be adjusted to minimize or eliminate the rack measured. A little bit of differential tension was observed on some of the strands, and the second from the left cable in the left set of cables of the left gate was tensioned despite being at the iimit ofthe guide block?s tension adjustment. The differential tension noted didn?t appear to have an adverse effect on operation and the cable take up was smooth, but significant differential tension can overload cables and reduce a cables operation life or cause failure of the cable. Ail gates opened relatively smoothly, though the right gate, the gate with the most rack, ?sang? a bit. As with the December 2007 inspection some slight chatter and hum was noted from time to time, but nothing alarming was heard or observed. The lift drive gears, which are greased yearly, had adequate lubrication. The stainless steel multi-strand 22-mm cables were not treated with a lubricating dressing during the test. The gate members and seals appeared to be in good condition. The bronze guide shoes were noted to have some normal scuffing during the 2007 inspection, and I did not notice any unusual wear beyond that mentioned. The usual debris accumulation was trapped on some of the gate members; this is removed yearly. The protective coatings on the gates and structural members remain intact, and no signs of distress were noted on the piers, decks, or sill. The upstream chute walls and floor were in satisfactory condition, though the concrete at the gate entrances sheds aggregate with light hand rubbing and Is not as durable as would be expected Despite the lack of surface toughness no excessive wear was noted within the concrete examined The owner hired HDR to inspect and evaiuate the spillway gate lift cables. Each gate is lifted with two sets of six cables attached to the lower corners of the gates using guide blocks working through a pin with bolt connections. The cables are reportedly original to the dam and therefore more Sheet 2 of 10 INSPECTION DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6 Saptember 2013 Observations and Comments than forty years old. USACE Engineering Manual EM 1110-2-3200, dated 30 September 1998, recommends that wire rope used on gate-operating devices be assumed to have a maximum service life of 20-years. While the condition of the cables is surprising good considering their age, limited and localized areas of high wear are evident. While infrequent and localized, HDR Engineers noted evidence of peening, birdcaging, corrosion, abrasion, broken wires, and core exposure. Since any of these deficiencies can be reason enough to replace a cable, along with their 40-year plus age, it appears the cables have reached the end of their useful life. With the actual service life extended to more than twice the recommended time, prudence dictates that cables should be replaced as soon as it reasonably possible for the owner to do so. Some of the guide blocks into which the lower end of the cables are anchored show a degree of eccentricity in relation to each other and to the direction of cable tension. Part of the eccentricity is caused by rust bloom between adjacent blocks, while eccentricity at the end blocks is exacerbated by the outboard centering washers pinching the bolts inward where they wrap around the pin. Eccentricity at the blocks can damage, fatigue, and reduce the tensile capacity of the cables. When these blocks are replaced along with the attending cables, care should be given to eliminate eccentricity at the blocks by revising the washer thickness and spacing between the block bolts connections, or by providing properly machined spacers of the appropriate width. . . DWR1261(rev.10i09) Sheet 3 of 10 INSPECTION DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of inspection 6 September 2013 Each gate is lifted with two sets of six cables attached to the lower corners of the gates using guide blocks working through a pin with bolt connections. Some of the guide blocks into which the lower end of the cables are anchored show a degree of eccentricity in relation to each other and to the direction of cable tension. Part of the eccentricity is caused by rust bloom between adjacent blocks, while eccentricity at the end blocks is exacerbated by the outboard centering washers pinching the bolts inward where they wrap around the pin. DWR1261 (rev. 10mg) Sheet 4 of 10 INSPECTION DAM AND RESERVOIR IN CER STATUS Name of Dam New Buiiards Bar Dam No. 1034 Date of Inspection 6 September 2013 Each cable is taken up within a separate Spool groove, six of which are arrayed together to accommodate the cables from one side of the gate. Sheet 7 of 10 INSPECTION DAM AND RESERVOIR IN CER STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6 September 2013 . . .?Ii . Misalignment of the feed for the cables to the spool grooves can cause abrasion between the cable and groove sides (abovenakur?~The contact zone between the lift cables and the gate skin plate is an area of increased wear, fatigue, and corrosion. DWR1261 (rev. 10/09) Sheet 8 of 10 INSPECTION DAM AND RESERVOIR IN TIED STATUS Name of Dam New Builards Bar Dam No. 1034 Date of Inspection 6 September 2013 A relatively small electric motor running on 208 volts and drawing about 20 amps runs through a large, single speed, gear reduction transmission to provide the torque required to lift a gate.241; 3: A long torque shaft connects the spools for opposite sides of each gate. DWR1261 (rev. 10109) Sheet 9 of 10 INSPECTION AND RESERVOIR IN CEP STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6 September 2013 .. i; - - "in In addition to the three electrical power sources a 1968 vintage Volkswagen (VW) motor can be used to lift the center gate through a direct drive transmission in an emergency. My impression, after watching this motor raise and lower the center gate one foot, is that this unit is marginal at best and likely unsuitable for reliable operation. DWR1261 (rev.10!09} Sheet 10 of 10 - a i131 - 11it. \?1'1 21.1. 1M 31053333? 33611119.. @?imi' {3-15} 53333443 5315311213 Fax: {411315} 45551461 5375111 3313911311-3393}, 3:111:13: 1211111. 3.8.3.. Webs. 232E13- 333733 E33133 .131.{33333333393313.1513 9:133:11: 1325311251131 13' 3:111:11- E3L~?w1i111911i 1111?. E33331 3911131113913 E19. .3111: 33.2836 3323:33331 2? 31133111211: N11111: 3113.11 13; 3111? 1311111. .. 0111 .111it11'111j. {3.1111111131111111}: 310191 N11111: 111115: $593.31, 1.2132101111- 333131173317;- {311311111331 311331833 ?31171! 233331113 1:933:13 11.5 3.1333311: 3113;111:1311 E3311: .. sit-3111111. {3121;311:1211 31031313 331151111 E11115: 3339113321 3111115,. FE 333-1111111213. ?1113 113111151113. 3.3111311?- E0c11111e11?11 211191.11 11431112313111 $33: {2111115 1211" 3531.113. ?ffi?CE 3:111:19; 51' 1132111111? 1233131101111 with. 311331 Wade 13 the Yuba {3111;111:231 25139111. 33113311111? and 3339:13192130111 1131113 3113111??sz .111 {$3111 311E Fackage E35333 1:111 3111.111 733 2313:. {?33an E113 hi?d?ig 3111313935.. 13.313111211111111: No. was iss 1131i 31113111313313.3113 this: 11311513133101: [11311. Em ire Ewan 1111:11'1'311112133 ?1131 this: {113191.111 E53111: $351313: 113213 1311.11.33} ?111 33112-112 213113-133?? 21113. E31111 11:11:13.1 111133 31315113119113? 511117111 351:3 E11 33.3111 E1112. E3013 1-5 to start-1.1111. 1.11: 51311113030391" 1 AGES. ?31113: 3111611113131 111} Egg- M1313 Mimi E31136YCW 39.1111. (13117113111113: {:31 STATE OF CALIFORNIA It?! 6 CALIFORNIA NATURAL RESOURCES AGENCY DEPARTMENT OF WATER RESOURCES DIVISION OF SAFETY OF DAMS INSPECTION OF DAM AND RESERVOIR IN CERTIFIED STATUS Name of Dam New Bar Dam No. 1034 County Yuba Type of Dam Concrete Type of Spillway Gated ogee crest Water is 13 feet above spillway crest and 50 feet below dam crest. Elevation ~1915 Weather Conditions Sunny and mild Contacts Made Peter Wade, Vinh Tran, FERC Reason for Inspection Annual inspection Important Observations. Recommendations or Actions Taken - Continue careful monitoring of the foundation gallery seepage in advance Of the upcoming foundation grout curtain rehabilitation project. Significant changes in the seepage volume, or sanding, should be investigated and reported immediately to DSOD and the owner?s engineer. . DSOD should be invited to participate in the next radial gate exercise and outlet valve test. 0 Reduction of the right abutment slide monitoring interval to once per year, as proposed in the transmittal letter for the first quarter 2013 instrument data, is acceptable to DSOD. The previously observed transverse cracks along the chute floor appeared to be stable. The owner should continue to monitor the cracks following significant spillway releases or earthquakes. - As previously requested, the owner will either inspect the radial gate wire ropes to see if they have additional service life, orjust replace them. The owner?s goal is to complete this work in the fall, which is acceptable to DSOD. Conclusions From the known information and visual inspection, the dam, reservoir, and the appurtenances are judged safe for continued use pending completion ofthe upcoming foundation grouting program and installation of additional foundation monitoring instrumentation. Observations and Comments Da_m No signs of unusual stress were noted along the crest road or parapet walls. See photographs 1 and 2, for example. The transverse cracks along the crest appeared to be normal, and where used, the crack sealing material remains intact. The thrust blocks and adjoining abutments appeared to be stable and in satisfactory condition. No significant joint offsets, cracks, or signs of thermal scaling were observed along the faces of the dam, or along the thrust blocks. These features are shown in photographs 3 through 9. Rodent and vegetation control were satisfactory. The right gallery was traversed from the upper access to the sump. No indications of unusual stress or movement were observed. The overall trend of increasing seepage and sanding of some drains within this gallery is discussed in the seepage paragraphs below. Right abutment exploration tunnel TR2 at Elevation 1575 feet and tunnel TR1at Elevation 1402.5 appeared to be unchanged and in satisfactory condition. The light seepage and standing water were typical of previous inspections. The left gallery was traversed from the upper access to the sump. No indications of unusual stress or movement were observed. The grout edit at Elevation 1387.5 was pumped down, but the lowest portion could not be entered due to standing water. A drain outfall along the gutter in this 3 Inspected by WPennington 1' Photos taken? Yes No Date 5/4/13 I t! cc for Owner/Book Date of Report 7/10/13 DWR 1261 (Rev. 10i09) Sheet 1 of 15 I g] 1 '7 DAM AND RESERVOIR IN STATUS Name of Darn New Buliards Bar Dam N0, 1034 Date of inspection 6/4/13 Observations and Comments Spillway Outlet Seepage adit, at about dam station 19+00, had sand around the outfall. See photograph 10. This location is just past the corner in the edit. As discussed during the inspection, this location should be checked during the upcoming foundation grouting program. Seepage within the left gallery is discussed under the seepage paragraphs below. The ogee crest, chute walls and floor, and the piers were in satisfactory condition. See photographs 7, 11, and 12. The concrete hoist decks and the bridge decks appeared to be in satisfactory condition as well. The previously observed transverse cracks along the chute floor appeared to be stable. The owner should continue to monitor the cracks following significant spillway releases or earthquakes. The radial gates are test Operated yearly for FERC using normal and backup power. DSOD should be invited to the next test. The operating equipment appeared to be well maintained. See photograph 13. The radial gates were observed from the opposite band, from the upstream left abutment, from the bridge decks, and from the left outside training wall. The coatings remain in good condition. The visible bolted and weided connections also appeared to be in good condition. No signs of overstress or misalignment of the gate members were observed. The wire ropes appeared to be well maintained, but are original. As previously requested, the owner will either inspect the rope to see if they have additional service life, orjust replace them. The owner?s goal is to complete this work in the fall, which is acceptable to DSOD. Cleaning the debris from the radial gates is a cumbersome operation, but is needed on a regular basis to remove bird droppings and moisture trapping dirt and debris. In an effort to address this issue, the owner is considering the installation of walkways across the side of the spillway piers to improve access for inspections and maintenance. The iow level outlet passes thru the central portion of the dam. It was not in operation at the time of the inspection. A trash rack, bulkhead system, and gantry crane are located at the upstream side of the dam. The discharge is controlled by a 72-inch butterfly guard valve located just upstream from the 72-inch diameter hollowjet discharge valve. See photograph 14. The outlet valve was successfully tested for DSOD in November 2011. DSOD requires that the outiet system be capable of iowering the hydraulic head by 10 percent in 10 days, which is about 63 feet at this dam. The valve is restricted to a maximum discharge of1250 cfs, which is insufficient to meet the drawdown requirement. However, the spillway gates can lower the hydraulic head by about 53 feet. in addition, the 15-foot diameter power penstock on the right abutment can release 147 feet of head relative to the normal maximum water surface. The combined discharge capacity from ail sources is considered sufficient. Seepage conditions along the face of the dam and the abutments appeared to be normal. The gailery beneath the spillway had a small amount of seepage along cracks, but far less than under full head conditions. The overall volume of seepage within the galleries was much lower than under full head conditions. Overali, seepage in the right gallery remains above historic averages, as noted in the First Quarter 2013 Dam Safety Surveillance and Monitoring Report. Upslope of the Block 8/9 joint, the seepage (rev.10l09) Sheet 2 of 15 '3 DAM AND RESERVOIR IN CERF STATUS Name of Dam New Bullards Bar Dam N0, 1034 Date of Inspection 6/4/13 Observations and Comments fiow is mostly due to form drains. Seepage increases in magnitude dramatically from block 8 to the sump area. Sand can be found on the stairwell landings, in the gutters, and behind measurement weirs. - The owner has submitted plans for a grout curtain rehabilitation project along the right abutment that will initially focus on failed grout holes. During this phase of the program, the owner will also install devices to monitor the volume of sand entering the gallery through drain or grout holes, and will install additional foundation uplift monitoring instruments. Over a period of time the owner will clean the foundation drains along both sides of the darn foundation. Seepage in the left gallery appeared to be normal for the reservoir level. However, about 10 feet above the Elevation 1515 stairwell landing, seepage was exiting a failed grout hole at an estimated 5 gpm. Several of the adjacent drains appeared to be plugged. This location, and a similar one, will be investigated during the upcoming foundation grouting project. Prior to the foundation grouting project, the foundation seepage shouid be carefully monitored. Any significant changes in seepage, or sanding, should be reported immediately to DSOD and the owner?s engineer. The following comments are based on my review ofthe first quarter 2013 dam safety surveillance and monitoring report and on my field inspection. 9 Stress, strain, and joint meters read on five-year cycle, but not processed and not needed at this time. a Foundation deformation meters read annually near maximum reservoir level. Not read during the latest quarter. 9 Crack monitors read at maximum and minimum reservoir level. Not read during latest quaner Thermometers read quarterly. Temperature distribution and values were normal. Seepage weirs read weekly. See seepage discussion above. Uplift pressure meters - measured weekly. Data remains normal. Survey targets on dam face read annually near maximum reservoir level. Not surveyed during latest quarter. Plumb lines measured quarterly. Data remains normal. The dam continues to respond elastically to the changes in lake level and environmental conditions. No adverse findings were mentioned in the quarterly report. The owner?s engineer recommends that the instruments on the siide area from the right abutment be measured once per year instead of twice per week. This proposal, as outline in the owner's May 22, 2013 Dam Safety Surveiilance and Monitoring Report transmittal letter, is acceptable to DSOD. Based on my field inspection, my review of the monitoring report, and my discussions with the owner?s representatives, the dam remains in satisfactory condition for continued use pending the completion of the upcoming foundation grouting program. DWR1261(rev.10f09) Sheet 3 of 15 INSPECTION DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6/4/13 1. This View of the dam crest is looking towards the left abutment. Nothing unusual was observed along the roadway or along the parapet walls. Also see photograph 2. 2. This View of the dam crest is looking towards the right abutment. New Bullards Bar Darn, No. 1034 Yuba County WPennington 6/4/13 Sheet 4 of 15 INSPECTION DAM AND RESERVOIR IN Name of Darn New Bullards Bar STATUS Dam No. 1034 Date of Inspection 6/4/13 3. Upstream side of the right side of the dam and right abutment thrust block. 4. This View shows the right side of the dam and intake gantry crane. DWR 1261 (rev. 10mg) New Bullards Bar Dam, N0. 1034 Yuba County WPennington 6/4/13 Sheet i of 15 INSPECTION DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6/4/13 5. Much of the left side of the dam is shown. The gantry crane is out of the picture to the right. DWR 1261 (rev. 10/09) New Bullards Bar Dam, No. 1034 Yuba County WPennington 6/4/13 Sheet 6 of 15 INSPECTION DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6/4/13 6. The spillway entrance at the left abutment and the left end of the dam are shown. The metal pipe at the arrow is on of the nozzles used to wet the gate seals before gate operation. New Bullards Bar Dam, No. 1034 Yuba County WPennington 6/4/13 DWR1261(rev.10l09) Sheet 7 of 15 INSPECTION. DAM AND RESERVOIR IN STATUS Name of Dam New Bullarde Bar Dam No. 1034 Date of Inspection 6/4/The left side of the dam and the spillway structure are shown. Minor leakage from the gate seals is Visible along the spillway chute. The rock below and along the chute appeared to be sound and stable. New Bullards Bar Dam, No. 1034 Yuba County WPennington 6/4/13 Sheet 8 of 15 INSPECTION DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6/4/13 8. The left side of the dam is shown. The abutment contact appeared to be in good condition. The usual leakage from the adits was present. A small amount of foundation leakage may also be occun?ing about mid- slope along the steeper potion of the contact. New Bullards Bar Dam, No. 1034 Yuba County WPennington 6/4/13 DWR1261 (rev. 10109) Sheet 01? INSPECTION DAM AND RESERVOIR lN STATUS Name of Dam New Buliards Bar Dam No. 1034 Date of Inspection 6/4/13 9. This View of the left abutment shows the power penstock in the center of the picture. A slide area on the abutment is shown at the arrow. This area slid several years ago and was stabilized. The owner surveys monitoring points every two weeks, but no signi?cant movement has been detected since the monitoring points were installed in 2006. The owner is proposing to shift the monitoring cycle from every two weeks to once per year. Signi?cant rainfall or earthquake events would also trigger a survey. New Bullards Bar Dam, No. 1034 Yuba County WPennington 6/4/13 DWR1261 (rev. 10/09) Sheet A 01? i DAM AND RESERVOIR IN CERT STATUS Name of Dam New Bullards Bar Dam No_ 1034 Date of Inspection 6/4/13 10. The ?owing foundation drain outfall at about dam station 19+00 in the Elevation 1387.5 grout adit was showing sand. See arrow. The gallery is normally ?ooded and has to be pumped out to do an inspection. Therefore, the sand may not have been observed in the past. This gallery should be pumped out and inspected during the foundation grouting project. New Bullards Bar Dam, No. 1034 Yuba County WPennington 6/4/13 Sheet 11 of 15 INSPECTION DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6/411 3 11. The spillway walls and chute ?oor remain stable and in good condition. Minor seal leakage continues. The previously noted tight cracks along the chute ?oor should be checked following large releases and earthquakes. New Bullards Bar Dam, No. 1034 Yuba County WPennington 6/4/13 DWR1261 (rev. 10:09) Sheet _12_ of i INSPECTION DAM AND RESERVOIR IN CERT STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6/4/13 12. This View of the left radial gate is typical of all three gates. Debris that accumulates on the gates and trunnions is washed off occasionally. The owner is considering the installation of walkways across the side of the piers to facilitate maintenance and inspection of the gates. Transverse cracks along the chute ?oor are visible in the upper part of the photograph. Vegetation is growing in the transverse joints in each bay. See arrow for typical location. This growth should be removed if it isn?t cleared during the next spill. New Bullards Bar Darn, No. 1034 Yuba County \VPennington 6/4/13 DWR1261 (rev. 10mg) Sheet 13 of 15 INSPECTION DAM AND RESERVOIR IN CERT STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 6/4/13 13. The spillway gate hoist deck and equipment appeared to be in satisfactory condition. The owner is deciding whether to do a full inspection of the Wire ropes or move ahead with replacement. The ropes have never been replaced. However, a detailed inspection may that they have remaining service life. DWR 1261 (rev. 1009) New Bullards Bar Dam, No. 1034 Yuba County WPennington 6/4/13 Sheet 14 of 15 0' STATE OF CALIFORNIA CALIFORNIA NATURAL RESOURCES AGENCY DEPARTMENT OF WATER RESOURCES DIVISION OF SAFETY OF DAMS INSPECTION OF DAM AND RESERVOIR IN CERTIFIED STATUS Name of Dam New Bullards Bar Darn No. 1034 County Yuba Type of Dam Concrete arch Type of Spillway Gated ogee crest Water is 65.74 feet below spillway crest and 128.74 feet below dam crest. W8 1890.26 Weather Conditions Sunny and mild Contacts Made See attached list of attendees. Reason for Inspection Instrumentation inspection by FERC and others. Important Observations, Recommendations or Actions Taken On August 28, 2012, I and Chris Dorsey joined FERC and others for an inspection of the dam. FERC requested this inspection. Mr. Tran wanted to read a few selective instruments including couple crack monitors, seepage weirs, uplift pressure pipes, and plumblines to verify the data he was using for his failure mode analysis. Mr. Peter Wade representing the owner briefed the attendees on the safety measures such as fall protection arrangements and ventilation in the seepage galleries. Conclusions I From the known information and visual inspection, the dam, reservoir, and the appurtenances are judged safe for continued use pending completion and outcome of the foundation grouting program. Observations and Comments D_am We covered the entire dam crest beginning from the right abutment to left abutment with an emphasis on the transverse cracks on the dam crest. Photographs 1 to 4 show typical conditions along the roadway and the parapet walls. The roadway surface remains satisfactory, and the long standing transverse cracks remain stable. Spillway The ogee crest, walls, chute floor, and bridge piers were in satisfactory condition. All radial gates were fully down at the time of inspection. The radial gates were observed from the upstream left abutment, bridge deck, and left outside training wall stairwell. The concrete hoist decks, photograph 5, and bridge decks appeared to be in satisfactory condition as well. Outlet The low level outlet was not inspected during the inspection. Seepage Seepage conditions along the face of the dam and abutments appeared to be normal and not a concern at this time. Seepage in the left gallery remains relatively low and normal for the reservoir level. As always, the seepage in the right gallery remains high. A plan for remedial grouting is under development by the owner's consultant, Christensen Associates, Inc. In the interim, careful monitoring of the gallery seepage should continue. A Inspected by L. Sinqh Chris Dorsey Photos taken? Yes No Date of Inspection 8/28/2012 cc for Owner/Book Date of Report . 9/12/2012 1 DWR1261 (Rev. 10/09) Sh et 1 of 8 INSPECTION O. DAM AND RESERVOIR IN .ED STATUS Name of Dam New Bar Dam No. 1034 Date of Inspection 8/28/2012 Observations and Comments Instr. The instrumentation at this dam consists of following: . Stress, strain, and joint meter read on five?year cycle, but not processed and not needed at this time. . Foundation deformation meters read annually near maximum reservoir level. The latest data remains normal and fluctuates within a narrow range in response to annual reservoir cycles. 0 Crack monitors read at maximum and minimum reservoir level. Small response with each reservoir cycle. Data looks normal. Thermometers read quarterly. Temperature distribution and values were normal. Seepage weirs read weekly. Uplift pressure meters measured weekly. Data remains normal. Survey targets on dam face read annually near maximum reservoir level. Data normal. Plumb lines measured quarterly. Data remains normal. The dam continues to respond elastically to the changes in lake level and environmental conditions. The oil damping pots are not filled until the measurements are made. This is done because drainage water running down the pendulum shaft tends to overflow the pots. The pendulums are allowed to stabilize before readings are taken. On August 28, 2012, and Chris Dorseyjoined FERC and others for an instrumentation inspection of the dam. iVlr. Vinh Tran with FERC stated that he is in the process of performing the failure mode analysis of the dam and only selective instruments will be read to verify the data required for the failure mode analysis. Mr. Peter Wade representing the owner briefed the attendees on the safety measures such as fall protection and ventilation in the galleries. We started the inspection from the dam crest, beginning from the right abutment. Two of the cracks at the dam crest were measured with following readings: Block No.9, 2: 0.480" Block No. 13, upstream: 2:0.473? All the remaining cracks were visually inspected. Usually, crack monitors are measured semiannually at maximum and minimum reservoir levels. The inspection party entered the left seepage gallery from the left abutment access port. Each section of the gallery was closely inspected visually for concrete deterioration and other defects. The majority of the seepage weirs at the upper portions were either dry or have standing water in the gutter with no flow. Various instruments including piezometers, foundation drain holes, and seepage weirs were read before we descend to the lower section. Overall, the seepage flow in the left seepage gallery remains low. Chris and inspected a portion of the right gallery from the lowest block moving upwards to block 17. Foundation seepage flow in the right gallery remains very high. The majority of the foundation DWR1261trev.10i?09) Sheet 2 of 8 INSPECTION (Ir DAM AND RESERVOIR IN CERTI. .ED STATUS Name of Dam New Bullards Bar Dam Na 1034 Date of Inspection 8/28/2012 Observations and Comments drains were gushing out with significant pressure. The gutter along the gallery wall was overflowing and splashing covered the entire width of the gallery. Also as noted in past inspection reports, there was significant amount of silt and sand accumulated in the gutter, predominantly silt in the upper portion of the gallery and mostly coarse sand in the lowest portion of the gallery. We collected samples of the sediments for a review by our geologist (Photo 10). Mr. Wade stated that due to environment permit issues, remedial grouting program is likely to be delayed to next year or year after. 1. Typical condition along the crest road and parapets is shown in this View looking towards the right abutment, standing near Block 3. New Bullards Bar Dam, No. 1034 Yuba County L. Singh 8/28/12 DWR 1261 (rev. 10109) Sheet 3 of 8 INSPECTION C. DAM AND RESERVOIR IN .ED STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 8/28/2012 vb. 2. A close View one of the cracks. crack monitor pla 3. A close of the all teeinetaned on either side ?of the crack. New Bullards Bar Darn, No. 1034 Yuba County L. Singh 8/28/12 DWR1261 (rev. 10:09) Sheet 4 of INSPECTION 0. DAM AND RESERVOIR IN CERTI. .ED STATUS Name of Darn New Bullards Bar Darn No. 1034 Date of Inspection 8/28/2012 View of the right half face. One of the survey control point is located in the highlighted DWR 1261 (rev. 10109) area. New Bullards Bar Dam, No. 1034 Yuba County L. Singh 8/28/12 Sheet 5 of INSPECTION O. DAM AND RESERVOIR IN .150 STATUS Name ofDam New Bullards Bar Dam Na 1034 Date of Inspection 8/28/2012 6. 7. A typical View of the left seepage gallery. New Bullards Bar Dam, No. 1034 Yuba County DWR 1261 (rev. 10x09) Sheet 6 of INSPECTION O. DAM AND RESERVOIR IN CERTI. -ED STATUS Name of Dam New Bullards Bar Dam No. 1034 Date of Inspection 8/28/2012 L. Singh 8/28/12 AS. 9. Another seepage weir near block 16 New Bullards Bar Dam, N0. 1034 Yuba County Sheet 7 of INSPECTION 0r- DAM AND RESERVOIR IN STATUS Name of Dam New Bullards Bar Dam N0. 1034 Date of Inspection 8/28/2012 10. Sediments collected from the gutter in the right gallery. New Bullards Bar Dam, N0. 1034 Yuba County L. Singh 8/28/12 Sheet 8 of 8