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CA/NV AWWA Annual Fall ConferenceOctober 29, 2015
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• Most filters are run to failure – Extend Filter Asset Life
• Filters are last barrier for particulate and microbial contamination• Filter media breaks down with time
– Restore & Improve Filter Performance• Proactive program for maintenance of filters
– Media cleaning is 3-10 years– Media replacement is 10-20 years
• Ability to spread cost for initial rehabilitation • Predictable fiscal budgeting
Why Filter Asset Management
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The list is numerous and growing…◦ Primary and Secondary Drinking Water Standards Turbidity Inorganics (Arsenic, Iron, Nitrate, etc.) Organics (Coliform, Cryptosporidium, Dioxin, etc.) Emerging contaminants◦ IE<2SWTR Lower turbidity standards Remove microbial contamination Stricter monitoring and reporting◦ Stage 2 DBPR◦ And more to come…
– Condition assessment– Media sampling and analysis– Estimating the cost of renovations– Estimating the life expectancy– Developing a financial plan
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Components for Developing a Filter Asset Management Plan
Basics of Plant Condition Assessment
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FILTER PERFORMANCE INDICATORS SUMMARYParameter Characteristics Metrics
Filter Run TimesMono-media 24 hrs. to 72 hrs.
Dual Media or Multimedia 72 hrs. to 140 hrs.
Filtration RateOptimized
1.4 gpm/sf to4 gpm/sf
Surface filtration <1.4 gpm/sf
Filter Effluent Turbidity
Regulation <0.3 NTU 95% samples
Best practice ≤0.1 NTU
Optimized operations0.03 NTU to
0.05 NTU
• Physical Observations about filters– Media surface (mounds, cracks, craters, low
and high spots)– Mud ball diameter and appearance– Mud present on top of filters
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Plant Condition Assessment
• Observe backwash for even flow and boils– Check if the troughs are level with even flow– Check surface sweep for smooth rotation – Check backwash flow rates
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Plant Condition Assessment
• Observe the overall conditions of building– Paint, electrical, lighting, HVAC, flooring, I&C, concrete, windows,
doors– Clean filters do not help if the ceiling is falling in
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Plant Condition Assessment
Filter Ceilings in “Bad” Shape
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Filter Ceiling Debris
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Filter Media Condition Assessment
Media Analysis– Strategic & representative media sampling– Lab analysis & evaluation
• Detect mudballs, odors, colors• Multiple advanced organic & inorganic tests
– Biomass via ATP & HPC, particulates, metals & mineral deposits– Confirm & quantify issues such as CaCO3, SRB’s, Giardia, etc.
• Bench-scale chemical cleaning with variety of products• Microscopic high-resolution pictures to document physical condition• Sieve analysis to measure ES & UC of each unique media for comparison to your design
specifications
– Lab Report with Customized Recommendations (clean or replace)• No “over cleaning” or premature replacement• Presented and discussed with your staff
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Before After
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Before After
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Before After
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Before After
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Filter Cleaning
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Chemical Cleaning– Custom-blend for each filter sampled– Only NSF-approved products– Chemical injection & agitation followed by
backwashing (multiple applications if needed)
– BW monitoring (pH & turbidity)– BW neutralization before disposal if
required– Disinfect media, and entire filter system and
piping
New media and materials match plant specifications Only NSF-approved products by AWWA guidelines Turnkey service◦ Remove and dispose old media & gravel◦ Full underdrain cleaning and inspection◦ Wall inspection and repair and/or repaint surfaces◦ Underdrain repairs and replacement◦ Filter System upgrades (e.g. media, equip.) Engineering & permitting as needed◦ Order & install new media & gravel◦ Bring online & assist with disinfection and Bac-T samples
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Water Treatment PlantFilter Condition Assessment
Summary Report
Table of Contents Purpose ......................................................................................................................................................... 1
Executive Summary ...................................................................................................................................... 2
Condition Assessment Activities .................................................................................................................. 3
Condition Assessment Findings ................................................................................................................... 5
Filter 1 ....................................................................................................................................................... 7
Filter 2 ....................................................................................................................................................... 9
Filter 3 ..................................................................................................................................................... 11
Filter 4 ..................................................................................................................................................... 13
Filter 5 ..................................................................................................................................................... 15
Filter 6 ..................................................................................................................................................... 17
Condition Assessment Conclusion ............................................................................................................. 19
Condition Assessment Recommendations ................................................................................................ 20
Preliminary Scope of Work and Price Estimate ......................................................................................... 24
Exhibit 1 ....................................................................................................................................................... 28
• Initial Condition Assessment of your granular filtration system
• Schedule filter rehab and maintenance work over the chosen MP period
• Annual Condition Assessments throughout MP• Asset Management tool spreads and predicts cost
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Developing a Financial Plan
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• Upfront Renovations– Filter Components– Plant Components– Media Cleaning/Replacement
• Ongoing Maintenance– Pumps– Controls– Media Cleaning/Replacement
Spread the Cost or Lump Sum
Operation under Run to Failureor
Proactive Maintenance Program
Filter Maintenance Program – Benefits
• Restores and Improve Filter Performance• Extend Filter Asset Life• Responsible Asset Management through Condition Assessments• Rehabilitation to owners needs/wants/desires• Build future cost model for financial needs• Provides predictable fiscal budgeting
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Questions?
Contact Info:Dawn Halpern
Water System Specialist Utility Service Group
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