Title
Annual Update on the Wastewater System
Body
Overview
The DPU wastewater operations comprises two different divisions of operations:
1) Wastewater collections (WWC [GWS])
2) Wastewater treatment & reclamation (WWT)
The GWS-WWC crew allocates two to four crew members to perform scheduled O&M work, such as mainline flushing and lift station maintenance. The GWS/WP electricians (2) also perform support work on the lift stations, as they require considerable electrical work. There are twenty-six lift stations in the WWC system with varying electrical service sizes, depending on the power of the pumps. There are currently three 480V lift stations, and twenty-three 240V or 277V lift stations.
The GWS crew operates various equipment to maintain the WWC system:
• Inspection tools - SL-RAT sonic wave detector and the video cameras (mainline & service line)
• Flushing tools - vactor trucks/equipment, flushing trailer equipment, easement machine flushing equipment
• Root cutters (mainline and service)
The WWT operations division oversees the operation and maintenance of the two treatment plants in Los Alamos County - LA WWTP and the new WR WRRF. The LA WWTP processes (treats) approximately 0.8 M gallons per day and produces approximately 300 lbs. of solids per day, while the WR WRRF processes approximately 0.3 M gallons per day and produces approximately 150 lbs. of solids per day.
The two plants use somewhat different treatment methods: The LA WWTP is an activated sludge/aeration basin system, while the new WR WRRF utilizes an innovative space-saving oxidation ditch technology. The old WR plant utilized trickling filter (rock media) technology that was common in the 1960s but could not meet current EPA standards for nutrient removal.
Both plants will soon produce class-1A effluent, which is the best quality treatment possible. The WWT division also processes all solids in an in-house EPA-permitted compost facility that produces a high-quality, beneficial compost for domestic and industrial re-use.
WWC & WWT Accomplishments
• Near completion of WR WRRF - put into service on 5/14/2024 (minus solids handling)
• Near completion of LA WWTP filtration system
• Replacement of wash-water pumps and motor controls - saves tens of thousands of gallons of water per day
• Built new covers over the grit chamber at the LA WWTP to reduce humidity/steam being pulled into the HVAC system in the headworks building
• Developed backup power connection and protocol at the blower room to keep the aeration basins online during power outages
• Replaced/rebuilt some of the MCC buckets at the LA WWTP due to some motor start failures
• Continued to meet the NPDES permit at the WR plant during most of the year - improvement over previous years
• Acquired new sonic pipe condition assessment tool - SL RAT (sewer line rapid assessment tool) to inspect pipes more quickly
• Eliminated Ridge Park Lift Station - just in time, as it was failing and in need of major upgrades
• 43rd St/Urban - North Community line reroute
• Main Line Flushing: 102,652 feet
• Transition to solid-state controls and SCADA at Range Road lift station
• Began transition to Ignition controls software at LA WWTP, following the integration process at the WR WRRF - a major improvement, and timely since the old Allen Bradley “FactoryTalk” software was outmoded and in need of major upgrades.
• New staff - only two WWT operators remaining to achieve Commercial Drivers License; many have achieved Level I & II Utility Operator Certification from the NMED
• Development of WWC SOP - EPA compliance requirement
• New GWS staff is fully trained on all WWC equipment and response procedures
• New WWT staff is developing quickly on plant operations and procedures
• Two of the newer operators have been training in laboratory and reporting procedures and are becoming quite proficient
WWC & WWT Challenges
• Overuse of the vactor trucks - DPU has two, but they are so heavily used and one or both is commonly out of commission, negatively affecting workflow on several processes
• Staff resources - water line breaks are crew intensive and require a vactor unit
• Much of the GWS and WWT staff is new, so there is much to learn
• Aging infrastructure - clay pipes that allow root intrusion
• Problematic infrastructure - older, non-standard installations in backyards, etc.
• Flushable wipes - proliferation of these materials causing clogs and backups
• Lift Station maintenance and component glitches and failures - difficult to impossible to predict
• New technology and changes in operating procedures
• Training
• Safety
Strategic Planning
• Continue to invest in workforce - WWC-GWS and WWT staff
• Engaged and well-trained workforce is critical to the WWC-GWS and WWT divisions
• Develop & update workflow SOPs to continually have focused benchmarks
• Cross-train staff on all workflows
• WW Collections is very equipment intensive - ensure equipment is well-maintained and rotated/replaced before critical failures occur, i.e. the vactor equipment.
• DPU will need to address the vactor maintenance issues with LAC-Fleet because it is critical for situational response
• Lift stations need constant attention. Need to develop “deeper” SOPs to catch critical problems before they occur, i.e. pump motor & electrical testing, panel component testing, detailed pump inspections, regularly scheduled component replacements
• Assess feasibility of replacing “service main” installations (multi-service sewer lines)
• Assess feasibility of replacing or lining old, vitrified clay (VCP) mains susceptible to root intrusion
• Continue asset management program. This is a very important process
Attachments
A - Annual Presentation_Wastewater Systems