Stock Pond (Highgate No. 6) FINAL ANNUAL STATEMENT BY SUPERVISING ENGINEER RESERVOIR NOT SUBJECT TO THE RESERVOIRS ACT 1975.

Size: px

Start display at page:

Download "Stock Pond (Highgate No. 6) FINAL ANNUAL STATEMENT BY SUPERVISING ENGINEER RESERVOIR NOT SUBJECT TO THE RESERVOIRS ACT 1975."

Chad Tyler Blankenship
8 years ago
Views:

1 Stock Pond (Highgate No. 6) ANNUAL STATEMENT BY SUPERVISING ENGINEER RESERVOIR NOT SUBJECT TO THE RESERVOIRS ACT 1975 FINAL October 2011 Supervising Engineer Dr A K Hughes Atkins Water Woodcote Grove Ashley Road Epsom Surrey KT18 5BW

2 Atkins DOCUMENT HISTORY RECORD Doc No. Title: Report on an Inspection - Stock Pond Rev Date Description/Reason for Issue Orig Ckd Appd A Final issued to Client AKH AKH AKH

3 CONTENTS 1. NAME OF RESERVOIR 1 2. NATIONAL GRID REFERENCE 1 3. NAME AND ADDRESS OF UNDERTAKERS 1 4. NAME AND ADDRESS OF SUPERVISING ENGINEER 1 5. DATE OF LAST INSPECTION AND NAME OF INSPECTING ENGINEER 1 6. SITE VISIT OF SUPERVISING ENGINEER General Monitoring and Records Dam Overflow Works Outlet Control Structures Pipework and Valves of the Dams Seepage/Drainage Flows Settlement and Movement Instrumentation Area Downstream of the Dam 4 7. FINDINGS Records (Section 11) Section 10 Inspection Recommendation of Inspecting Engineer regarding matters to be watched (Section 12.(2)) Changes Maintenance Suggestions Other 5 8. SIGNATURE OF SUPERVISING ENGINEER AND EXPIRY DATE OF FIVE YEAR PANEL APPOINTMENT 5 Appendix A Summary Action Sheet

5 Outlet Control Structures 3 6.6 Pipework and Valves of the Dams 3 6.7 Seepage/Drainage Flows 3 6.8 Settlement and Movement 3 6.9 Instrumentation 4 6.10 Area Downstream of the Dam 4 7. FINDINGS 4 7.

4 RESERVOIR NOT SUBJECT TO THE RESERVOIRS ACT 1975 ANNUAL STATEMENT BY SUPERVISING ENGINEER 1. NAME OF RESERVOIR STOCK POND situated in the east part of Hampstead Heath, City of London. 2. NATIONAL GRID REFERENCE TQ NAME AND ADDRESS OF UNDERTAKERS Corporation of London Guildhall London EC2P 2EJ 4. NAME AND ADDRESS OF SUPERVISING ENGINEER Dr A K Hughes BSc PhD DMS CEng FICE FCIWEM MIMgt Atkins Water Woodcote Grove Ashley Road Epsom Surrey KT18 5BW Redacted 5. DATE OF LAST INSPECTION AND NAME OF INSPECTING ENGINEER Not applicable. 1 Final October 2011

NAME AND ADDRESS OF UNDERTAKERS Corporation of London Guildhall London EC2P 2EJ 4.

5 6. SITE VISIT OF SUPERVISING ENGINEER 6.1 General I examined the reservoir on the 1 st April I was accompanied by Redacted and a number of officers from the City of London. The weather was fine, dry and cool and in the preceding two weeks had been generally dry with light showers. The reservoir on the day was just full and spilling by about 2mm. 6.2 Monitoring and Records No statutory records are kept for this reservoir. 6.3 Dam Upstream Face What could be seen of the upstream face appeared to be in a satisfactory condition with good line and level. The slope supports a significant number of mature trees. There is minor erosion between the root systems of the trees. I advise that the trees must be managed. I advise the erosion be repaired. Crest The crest appeared to be in a satisfactory condition with good line and level. The crest is partially surfaced. I advise that vegetation on the crest needs to be managed to enable inspection/examination/access. Downstream Face The downstream face appeared to be in a satisfactory condition. The vegetation is rather coarse with trees, saplings, brambles and little grass cover. I advise the vegetation on the downstream face needs to be managed and the situation improved with attempts be made to improve the grass cover. There is some infrastructure off the right hand mitre. Thus I advise the brambles on and beyond the right hand mitre be cleared. 2 Final October 2011

2 Monitoring and Records No statutory records are kept for this reservoir. 6.

6 6.4 Overflow Works The approach to the overflow was clear. The overflow pipe is housed within a boxed screen which makes it almost impossible to clear but because the reservoir is isolated from the public and dogs very little problems are experienced with debris. However there was some debris in the screen. I would advise that in an extreme event there will be floating debris and the Corporation should adapt the overflow so that it could be unblocked in an emergency. I advise the outlet structure needs to be rebuilt. The overflow is said to run down off the right hand mitre and through a manhole to the stream. The manhole was found and the position of the end of the pipe has now been found. I advise the area at the end of the overflow be kept unobstructed. 6.5 Outlet Control Structures Not applicable. 6.6 Pipework and Valves of the Dams Redacted There is a valve pipe associated The pipe discharge point has been found. The route of the pipe has been traced and the outlet found. I advise that an outlet be provided via a manhole in the area downstream of the toe. The valve was opened but there was no flow. I advise the drawoff pipe be cleared of its blockage/obstruction. 6.7 Seepage/Drainage Flows There was no evidence of any seepage or drainage flows at the toe of the dam. The face and mitres was found to be firm and dry. 6.8 Settlement and Movement I saw no signs of settlement or movement to give me cause for concern. 3 Final October 2011

debris. However there was some debris in the screen.

7 6.9 Instrumentation There are no instruments installed in or on the embankment Area Downstream of the Dam Immediately downstream of the reservoir is the Ladies Bathing Pool. There appears to have been no changes in the immediate area downstream of the dam. 7. FINDINGS In general the embankment is in a satisfactory condition. 7.1 Records (Section 11) Statutory records are not kept. 7.2 Section 10 Inspection Not applicable. 7.3 Recommendation of Inspecting Engineer regarding matters to be watched (Section 12.(2)) Not applicable. 7.4 Changes There have been no significant changes since the last inspection. 7.5 Maintenance Suggestions The vegetation must be controlled. Consideration be given to modifying and improving the overflow so debris on the inside of the screen can be cleared and it is in a better condition. 4 Final October 2011

7.2 Section 10 Inspection Not applicable. 7.3 Recommendation of Inspecting Engineer regarding matters to be watched (Section 12.(2)) Not applicable. 7.4 Changes There have been no significant changes since the last inspection.

8 The drawoff pipe be unblocked. 7.6 Other None. 8. SIGNATURE OF SUPERVISING ENGINEER AND EXPIRY DATE OF FIVE YEAR PANEL APPOINTMENT Redacted Date 21 October 2011 Signed Dr A K Hughes Supervising Engineer (Appointment to All Reservoirs Panel until 31 May 2016) 5 Final October 2011

APPOINTMENT Redacted Date 21 October 2011 Signed Dr A K Hughes

9 APPENDIX A SUMMARY ACTION SHEET 6 Final October 2011

10 Summary Action List Reference Action By Whom Date Completed 6.3 the trees must be managed on the upstream face. 6.3 vegetation on the crest needs to be managed to enable inspection/examination/access. 6.3 the vegetation on the downstream face needs to be managed and the situation improved with attempts be made to improve the grass cover. 6.4 in an extreme event there will be floating debris and the Corporation should adapt the overflow so that it could be unblocked in an emergency 6.4 the outlet structure needs to be rebuilt. 6.4 the area at the end of the overflow be kept unobstructed 6.6 an outlet be provided via a manhole in the area downstream of the toe 6.6 the drawoff pipe be cleared of its blockage/obstruction 7 Final October 2011

4 in an extreme event there will be floating debris and the Corporation should adapt the overflow so that it could be unblocked in an emergency 6.

CLIFTY CREEK PLANT MADISON, INDIANA

2015 DAM AND DIKE INSPECTION REPORT GERS-15-018 CLIFTY CREEK PLANT MADISON, INDIANA PREPARED BY GEOTECHNICAL ENGINEERING AEP SERVICE CORPORATION 1 RIVERSIDE PLAZA COLUMBUS, OHIO Annual Dam and Dike Inspection