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2022-03-01 CC Agenda Packet - PRESENTATION - ITEM D14 - High Points of the Advisors ReportHigh Points of the Advisors Report Report of the Ad Hoc Advisory Committee Advisors on the July 11, 2021 Flooding at the Hyperion Water Reclamation Plant and Recommendations for Future Improvements Michael K. Stenstrom, PhD, PE Principal Author and Committee Advisor Committee Member Greg Good President, Board of Public Works Teresa Villegas Commissioner, Board of Public Works Committee Advisors Felicia Marcus Former Chair, CA Water Quality Control Board Mark Gold, D.Env. Deputy Secretary, CA Natural Resources Agency Gary Lee Moore, PE LA City Engineer Carol Parks General Manager, LA Emergency Management Department Elias Sassoon Director, El Segundo Department of Public Works Marcel Anaya Acting Lead Operator - Liquids Section, Hyperion Bruce Reznik Executive Director, LA Waterkeeper Tracy Quinn Director, CA Water Conservation & Efficiency— NRDC Robert Ferrante, PE Director, LA County Sanitation District Shelley Luce, D.Env. CEO, Heal the Bay Kishia Powell President, NACWA/COO, DC Water Don Smith, MS, PE, Wastewater Grade V Operator Retired Chairman of MWH and Former Hyperion Plant Manager Executive Summary • Describes the event and some of the timing, relies on CDM-Smith's and Brown and Caldwell's preliminary reports • Defines roles of CDM-Smith and Brown and Caldwell. Notes new sewer surveillance technology used by Brown and Caldwell • Summarizes CDM-Smith preliminary conclusions and electrical issues and needs for improvement -completion of the distributed control system and better alarms • Summarizes Brown and Caldwell's reports findings — little evidence for a surge of debris that clog the screens, but found some issues that need repair or cleaning • States that the likely cause is chopper failures which caused recycling of debris. ® Notes that there was a delayed acknowledgement of a high level alarm and that the barrier was not removed until early the next morning. • Notes LAC-DPH's delay in closing beaches • Recommends redesign to avoid debris recycling and development of a protocol between BOS and LA-DPH to develop a quick beach closure policy Sections Role of Ad Hoc Advisory Committee and its Advisors Recommendations in 7 sections Capital Improvements Conveyance System Assessments/Audits Operations — Procedures Operations — Training Operations — Staffing • Emergency Response • Conclusions Hyperion Simplified Schematic Influent wastewater flow by Wastewater �� g avity Bar Screens Grit Chambers Primary Clarifiers ebK'� - .-%% Aeration Tanks 5 Mile outfall pumps Secondary Clarifiers Points for Ocean potential flooding Capital Improvements Explanation of Recycling and Barrier 1 Transport sluice, fed with high Crane to remove pressure barriers plant effluent 1.4 Million gallons/day flow Sluice gate, upstream, Sluice gate, down stream, Mmotor operated, remotely motor operated, remotely controlled controlled. Raw wastewater, flowing by gravity to the plant U 0 0 T Water level before and after the screen Barriers or stop -logs, manually removed by connecting overhead crane to lifting eye bolts To Grit Chamber then rest of the plant Bar screen function schematic Rake Moves up and down Water Level 1 4 Head Loss Retained Flow Debris Hyperion bar screen Capital Improvements Explanation of Recycling Transport Sluice, operating at 1.4 million gallons/day flow rate Weir High Level Overflow returns screenings and water to the front of the bar screens and Barrier 2 Chopper Pumps 71 Drum Screens Choppers and ; Return water to Sprialifts front of bar screens M �� �• F M Trucks to landfill Return water to front of bar screens ` � • y � \ram . 1 M M AO - 4r 00 oe •W I � � f r f .. ti � ., �. i `� j; {�1 � Sr .. . � 4�5 y � J 7 �1 ,� 1 _ .fir � _ _ 7 � _ � - .,,. - , � ''-�aik+ i . • � �r �� '• � � � � L •�� �� :. h-.. :F'�„ S 'ram- + � •. ��+��f ,ti Capital Improvement Recommendations 1. Additional High Level Bypass to Grit Chamber that does not require operator interaction 2. Reworking road to reroute flood waters and gravity flow connection to emergency storage 3. Submarine doors to protect critical areas 4. Securing entrances to the tunnels 5. Redesign of screenings removal to prevent recycling 6. Motor current monitoring to detect increases in bar screen loads 7. Closed circuit TV to visually monitor the screens Conveyance System Improvement Recommendations 1. Problems found by Brown and Caldwell in their initial report to be repaired 2. BOS to develop a program to use the new survey technology to monitor headworks and conveyance system 3. BOS and BOE to participate in nation wide programs to identify increased accumulation in conveyance systems caused by reduced flow by reclamation and climate change 4. Communicate findings to other agencies Assessment and Audits 1. Rank alarms and alert staff to time to respond 2. Hyperion has had as much as 800 MGD storm flow and the plant currently treats an average of 260 MGD. Study the conveyance system to determine peak flows and assess risk to the plant from peak flows 3. Review needs for emergency power 4. Analyze the event to see what additional actions can be taken to miReview capabilities of the DCS system and see what additions are needed 5. Audit capabilities of the public information system Operations and Procedures - Headworks Evaluate responsibilities for the staff on duty to operate and maintain the headworks. Evaluate annunciating and responding to alarms, routine "boots on the ground" inspection of key process equipment, and documentation for actions to be taken. Develop a new standard operating procedure to identify best practices for using and removing barriers. Evaluate and develop revised procedures as appropriate for back up screens, choppers, and spiral lifts. Identify and implement improvements of documentation to ensure that all shifts practice the same procedures and communicate with each other. Develop and/or update to make sure new operators are trained for this critical function Create a standard inspection round for all shifts. Evaluate and conduct reviews (i.e. quarterly or other frequency as appropriate) of logs to identify potential problems and improve communication. Evaluate and develop as appropriate a specific plan of action with appropriate training for a future bar screen failure event. Retrain periodically on any such action plan and Training 1. Ensure back up operators are trained and cross trained for emergency response 2. Train to recognize and respond to emergency alarms 3. Train to coordinate system operation with DCT and Glendale treatment plants Staffing 1. Evaluate and update critical staffing needs 2. Evaluate needs for normal hours, evening hours, holiday hours, and forecast of large rain events 3. Determine what "call in" staff are needed 4. The headworks is one of the least desirable locations to work. Establish an incentive to work at the headworks Emergency Response 1. Adopt policies, protocols and training to promote a better intra and inter agency response 2. Coordinate a protocol with LA DPH to facilitate and accelerate beach closures 3. Develop a protocol to initiate additional water quality sampling 4. Evaluate modeling techniques to predict will affect beach water quality