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HomeMy WebLinkAboutSupplemental Information Received After Posting of Agenda - Item H5/22/2017 Presentation Overview Seal Beach Storm Drain System Y Definitions > SD System Elements D SD System Drainage Basins Overview West End Pump Station Audit — Review L West End Storm Pump Station (WEPS) Elements - Overview i WEPS History Chronology of Events (December 2t,2or6 through February 20, 2019) e Equipment Evaluation / Audit Findings Y Audit Recommendations — Equipment adjustments West End Pump Station Maintenance Program Peer Review of Audit Definition • What is a loo year flood (or protection)? Flood that has a 1% chance of happening independently each year. • A 25 year flood Flood that has a 4% chance of happening independently each year. • A io year flood Flood that has a lo% chance of happening independently each year. Flood Protection Goals • Major Goal Keep water at least 1' below finished floor elevations for a loo year flood. • Other Goals Arterials • io year flood - keep one lane of traffic open Local Streets • 10 year flood - maintain water below curb 5/22/2017 2 County of Orange Standard Flood Protection Goals Street 100 -Year Flood Level ® ■ i 2' Pad Elev. 1 10 -Year Flood Level' 2 5-Year Sump Conditions' Local Street Finished Floor of Lowest Habitable Room for Residences and Other Non -Flood Proof Structures -For ananal Ngh"y and Local shee( depth times velocity cannot exceed su. County of Orange Standard Flood Protection Goals q Street Medium Area Level 00-Year Flood Top of Curb Level 2. 12. 12' Pad Elev. 10 -Year Flood Level' Finished Floor of Lowest Habitable 25 -Year Sump Conditions* Room for Residences and Other Non-Flood Proof Structures Arterial Highway 5/22/2017 3 Seal Beach Storm Drain System er oasins 5/22 /2017 4 -- us.rwwa Ratty . . H'es1 ttd PmnP � �A� StAw _tz_ Va1LOLIF4 •_••••� er oasins 5/22 /2017 4 West End Pump Station WEPS Storm Water Basin Storm Drain System Elements • Hydrology and Hydraulics Analysis ( Master Plan) • Storm Water Runoff C • Open Channels • Streets and Gutters • Pipes/ Box Culverts • Catch Basin / Grates • Storm Water Pump St, 5/22/2017 5 m Mmn 't �* Area: 173 acres Protection Levels: loo years = 295 cfs 10 years = 200 cfs f Pump Station Capacity: 200 cfs s Pipe Covance System Capacity: approx. 115 cfs Storm Drain System Elements • Hydrology and Hydraulics Analysis ( Master Plan) • Storm Water Runoff C • Open Channels • Streets and Gutters • Pipes/ Box Culverts • Catch Basin / Grates • Storm Water Pump St, 5/22/2017 5 5/22/2017 Audit Review Audit Objectives: Y Document History of West End Pump Station • Review recent Pump Failures / Document Chronology of vents (Doe. 21, 2017 through Feb. 20, 2017) • Evaluate Existing Equipment and assess condition capabilities • Review past Maintenance Prrctices and provide recommendation for future of facilities maintenance West End Pump Station History 5/22/2017 Forebay and Wet Well 5/22/2017 - Section 2- History of West End Pump Station • Original Station constructed in 1959 with a capacity of 110 cfs • Provides flood control service westerly portion of the City • 2007 Capital Improvement Project rebuild entire pump station with all new components and structural improvements • Two new pumps installed, increased Station capacity of 225 cfs • Station includes a smaller 25 horsepower sump pump designed for low flows - Section 3- Chronology of Events 1. Rain in December 2016 2. Rain in early January 2017 3. Special City Council Meeting January 17, 2017, and Funding Authorization 4. Pump Removal, Inspection and Repairs 5. Re- installation and start up 6. Rain in February 2017 Rain in December 2016 • Initial Pump Failure of Pump 2 on evening of December 21, 2016. • Lead pump manually switched from Pump 2 to Pump 1. • Electrical contractor, MacDonald called out on December 22, 2o16. • Not an electrical or VFD issue, thought to be mechanical 5 /22/2017 1 5/22/2017 Rain in early January 2017 • Wednesday, January 4, 2017 significant rain event causing Pump 1 to operate. • Inspection by Orange County Pump Company (pump maintenance contractor) on January 5, 2017. • Inspection by Cascade Pump Company (pump manufacturer) and Flo- Services, Inc. (pump maintenance contractor) on January 6, 2017 Special City Council Meeting and Emergency Proclamation • Tuesday, January 171', City Council held a special public meeting to discuss the failure of pumps at the West End Pump Station • City Council approved Budget Amendment in the amount of $200,000 • To be used for transportation and repair of non- functioning permanent pumps by Flo- Services, Inc. and Cascade Pumps • Also for portable pump rentals, fuel, AKM design audit, and contingency during rain events Pump Removal, Inspection and Repairs • Both pumps disconnected, motors removed and then transported to manufacturer (Cascade Pumps) for diagnostic review and repairs. • Both pumps fully disassembled for review with City Staff and consultants present. Inspection and Repairs duwmtly W NmI A.X EMInIMT�� 5/22/2017 3 Inspection and Repair Conclusions. • Cascade concluded that neither pump failed due to internal defects or wear, but from trash lodged between the propeller and bowl. Re- installation and Start up Flo- Services, Inc. transported and re- installed both pumps on Wednesday and Thursday, February 1 & 2, 201'7 Flo- Services, Inc., VFD technician, City staff and AKM present on Friday, February 3, 2017 for initial startup and testing o Light rain event on Friday, February 3, 2017 aided pump testing All present again on Monday, February 6, 2017 during moderate rain event for additional monitoring and testing. 5/22/2017 4 Rain in February 2017 • Pump No. 1 set as lead pump • Received alarm that Pump No. 1 went offline around 6:30 PM and that Pump No. 2 took over automatically • Proceeded with diagnostic testing of Pump No.1 controls and VFD Friday night • Confirmed that a pump clog was the most likely cause. • Pump Contractor called out on Sunday to confirm clog and remove • Pump Contractor returned on Tuesday remove pump flute and remove clog from propeller Lodged debris s /22 /zov - Section 4- Equipment Evaluation, Findings and Recommendations 1. Pumps 2. Motors 3. Variable Frequency Drives 4. Control Systems 5. Generator 6. Trash Rack Pumps 5/22/2017 I 5/22/2017 Pump Recommendations Leave catch basin screens in place during the storm season. Patrol flood prone areas of the City during rain events to ensure catch basin screens are unobstructed. Improve the trash rack at the pump station by closing off ungrated openings, and reducing the slot lengths of the eadsting grate. • Clean the pump station forebay and the wet well after every major storm event to prevent the accumulation of trash. Implement a program to clean accumulated trash from the storm dram system Inspect the interior of each pump after every storm for debris. Remove any foreign material which may be observed. Provide permanent wiring to each pump's oiler system solenoid valve. • Install a small wet well low level evacuation pump to drain the wet well to facilitate inspection and maintenance of the pumps. Motors ��1 Motor Recommendations • Oil should be changed after each storm season. • Testing of the motor winding insulation should be performed once per year to verify that it is in good working order. The test should be performed at least 3 months prior to the storm season so that if a problem is discovered, the motor can be repaired and reinstalled prior to the start of rain. • The oil level site gauges should be replaced soon to stop the minor oil leaks which have developed. Variable Frequency Drives (VFDs) 5/22/2017 8 VFD Recommendations Reprogramming of the Pump 1 VFD should be conducted to eliminate over torque alarm which is being generated. If continued failure of the pumps due to debris occurs, consideration should be given to increasing the minimum speed setting. The time /date calendar should be programmed into both drives so that an accurate record of when an alarm event occurred can be maintained. Contr 5/22/2017 W Control System Recommendations • Reprogram the Murcal panels to provide automatic pump alternation. • Verify back -up float system operation. • Have City's SCADA consultant review and correct the cause of inaccurate data being collected at the City's SCADA central monitoring station. Generator 5/22/2017 10 Generator Recommendations It is recommended that the generator be tested once per year, either with a load bank, or by running a pump to verify it is working properly under loaded conditions. Trash Rack 5/22/2017 11 Trash Rack Recommendations • Either modify or replace existing trash rack grates to reduce the current slot opening. • Seal existing openings under the bottom row of grates, and on the sides of the rack. - Section 5- Maintenance Program Evaluation • Current Maintenance Program Includes weekly inspections of: • Oil Reservoir • Forebay water level • Generator conditions • Pump Control Panel, VFDs, and Controllers • General site 5 /22/2017 12 Recommended Maintenance Program Pump Station • Manually exercise pumps once per month • Clean forebay and trash rack prior to the rain season • Change oil once per year • Inspect motors • Annually test the generator under load conditions • Test float switch annually • Clean level transducer heads monthly • Verify alarm dialer monthly • Check flap gates prior to rain season • Follow all maintenance protocols in the Operation and Maintenance Manuals for each piece of equipment Recommended Maintenance Program • Storm Drain System Catch Basin Screens Video inspect storm drains 13 Audit Peer Review - Lee and Ro, Inc. Lee Badertscher, PE, 30 Years of Experience • Registered Civil Engineer California & Utah, Registered Control Systems Engineer, Registered Electrical Engineer • Performed third party peer review and plan check for City of Glendale's Doran Pump Station Upgrade and • Performed QA /QC review for an engineering evaluation Sand Canyon Pump Station • Performed QA/QC for the Bitter Point Pumping Station for the Orange County Sanitation District. • Project Manager for the Yorba Linda Blvd. Booster Station and Pipeline Project for Yorba Linda Water District • Project Manager for Arrowdale Storm Drain, Los Angeles County Department of Public Works. 5/22/2017 14 Lee and Ro, Inc. Review Results • Pump start-up time Lee and Ro concurs with decreased ramp time • Inlet capacity • Pumps can discharge 200 cfs • Inlet system can convey 115 cfs • Lee and Ro concurs that flooding is likely in a storm that generates more than 115 cfs • Control Systems Lee and Ro recommends a comprehensive control strategy Lee and Ro, Inc. Review Results cont. • Standby Generator Lee and Ro concurs with testing recommendations • Trash Rack Lee and Ro concurs with improvement recommendations to trash rack • Maintenance Lee and Ro believes AKM's maintenance practice recommendations are reasonable and prudent 5/22/2017 is Summary of Action Items • Repair SCADA System • Install New Wire & Conduit to Oiler Solenoid • Improve Trash Rack • Implement Enhanced Maintenance Procedures ➢ Clean Pump Station Forebay After Each Storm ➢ Clean Storm Drain System Annually ➢ Leave Catch Basin Screens in place during storm season • Initiate Comprehensive Operator Training Program 5/22/2017 16