Restoring the West Point Treatment Plant Pacific Northwest Pretreatment Workshop Sept. 12, 2017

Transcription

1 Restoring the West Point Treatment Plant 2017 Pacific Northwest Pretreatment Workshop Sept. 12,

2 Today s Presentation Overview of the system West Point flood and response/restoration Outreach to industrial system users What s next 2

3 West Point Treatment Plant Averages 90 million gallons a day during dry months. Wet weather design capacity of 440 million gallons a day. Receives an estimated daily flow of 9.6 MGD from significant industrial sources. 3

4 The West Point System Serves about 700,ooo people, mainly Seattle and its Northwestern suburbs. Treats domestic, commercial & industrial wastewater; Serves City of Seattle s combined stormwater & sewer system. 3 wet weather treatment plants (Alki, Carkeek, Elliott West) 4

5 What Happened Feb. 9 Power and equipment failure during a storm led to flooding inside the West Point Treatment Plant. 180 million gallons of stormwatersewage discharged to Puget Sound. Two smaller bypasses occurred on Feb , for a total of 235 million gallons. Damage temporarily reduced plant capacity, treatment level.

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7 February 9,

8 Immediate Response Dewatering, initial cleanup employee safety priority Emergency declaration Posted beaches and monitored water quality to protect public Flashlight shows water line 8

9 Immediate Response Mobilized crews and equipment for 24/7 response; brought in contractor support Assessment of damage Timeline & critical path Developed plans for restoring treatment processes 9

10 Recovery/Restoration Shed flows to Alki & Carkeek, Brightwater & South Plants Restored primary treatment and disinfection within 18 hours Restored critical equipment by April 30 Recolonized biology in the secondary process Woke up digester biology Resumed permit standards May 12 10

11 Damage & Repairs Ongoing Type of Equipment Damaged Equipment Count 12 x 12-Foot Tunnels 1 Mile Electric Motors 149 Pumps 127 Electrical Motor Control Centers Buckets 200 Electrical Panels 125 Electrical Transformers 25 Local Electrical Control Stations 125 Light Fixtures >2000 Outlets and Switches >1200 Instruments >125 Solenoids >200 11

12 Communications Immediate response: proactive, timely notification using established protocols. Consistent key messages; no speculation Transparency: ongoing updates via web, media outreach, briefings & community meetings. Created an incident response website with FAQ s, press releases. Environmental community briefings and website with water quality data. 12

13 Outreach to Industrial Users Focused specifically on largest dischargers No restrictions on discharging Engagement around pretreatment BMPs Enhanced sampling & inspections for certain facilities Carefully tracked monitoring data 13

14 Outreach to Industrial Users Voluntary Measures: Defer discretionary activities that would increase loading to WP Increase BMPs such as sweeping and CB cleaning Reduce discharge volumes during high precipitation events Maintain pretreatment systems in optimal condition. 14

15 Monitoring Puget Sound West Point wastewater discharge Routine Effluent Monitoring - daily/weekly samples Additional Effluent Analysis during limited treatment Untreated discharge of 235 MG was approximately 20% of our total CSO volume in a year. 15

16 Monitoring Puget Sound Discharge effects characterization Marine monitoring plan during West Point restoration Additional offshore locations and increased sample frequency Marine offshore monitoring (fecal bacteria, dissolved oxygen, nutrients, chlorophyll) Beach monitoring (fecal bacteria, nutrients) 16

17 What s next: Acting on Recommendations Root-cause analysis After-action review County Council oversight report (Independent Review) 50-Year Assessment Asset Management Review Long-Term System Plan Evaluating capital priorities 17

18 Major Items for Immediate Future Replaced damaged equipment Added/upgraded electrical feeds Prioritizing alarms Strengthening training programs 18

19 Looking Ahead Opportunities to add capacity & redundancy Protect water quality and public health for an aging system affected by climate change Looking at system-wide loads Capital investments & asset management Maintaining affordability 19

20 Questions Mark Isaacson, Director Bruce Kessler, Assistant Director King County Dept. of Natural Resources and Parks, Wastewater Treatment Division Get updates online at 20