ccao/ceao annual winter conferenceccao/ceao annual winter conference december 8, 2015. 2 water loss...
TRANSCRIPT
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Water LossWater System Evaluation for a
Better Understanding of
Real and Apparent Water Loss__________
Daniel R. Schaefer P.E.
CCAO/CEAO
Annual Winter Conference
December 8, 2015
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Water Loss Review – Why An Annual Update?
■ Quite Simply… It is what our water customers expect… that we manage and spend their hard earned money on safe, reliable and high quality water systems!
■ The water distribution system asset value is typically 75 to 80% of the total water system. Regular water loss review annually is key.
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Water Loss Review – Why An Annual Update?
■ Water is the ONLY utility that we ingest, so it is critical that we manage and maintain our water systems to the best standards
■ AWWA Standards
■ Ten State Standards, NSF
■ ORC, OEPA, and Local Regulations
■ The AWWA, acceptable standard is 10% - 15% line loss
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Managing Water Loss to Reduce Revenue Loss
■ AWWA M36 is a best practices method for a single approach recognized worldwide for water loss studies
■ In the past, inconsistent water loss measurements varied among water utilities nationally and internationally
■ Trend analysis on system parameters
■ Determine a fair revenue recovery equitable among all rate payers
■ Better understanding of water operations including identifying lost revenue
■ Provides a proactive approach to long term maintenance for leaks
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Managing Water Loss to Reduce Revenue Loss
■ Improve supply delivery and customer metering to reduce revenue losses.
■ Water loss study reassures customers, shareholders, and bondholders
■ Maintains separate fields for registered usage and billed usage
■ Registered usage – actual flow thru meter
■ Billed usage – Customer billing
■ Reviews interconnections with other area water utilities
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Water Loss Starts with Water System Evaluation■ Must understand the water system
assets, attributes, operations and water usage.
■ Use mapping and GIS with system attributes
■ Water supply and billing records? metered and unmetered with address and location? usage and type?
■ Asset conditions? Break and leak maintenance data? meter calibration testing? trends of operations?
■ Policies on how leaks and breaks are managed? meters maintained? losses calculated?
■ System pressures using telemetry and SCADA data?
■ Customer meter testing program? Main flushing?
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Water Loss Process Strategies■ Identify a Core Team to obtain
records and data
■ Select a time period to review water loss records
■ Use a Consistent Unit of Measurement (i.e., MG/yr.)
■ Understand Water Supply – Use Maps, GIS, Model, etc.
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Water Loss Process Strategies■ What is the Authorized Consumption?
■ Billed Metered Water billing records
■ Billed Unmetered Estimated billing
■ Unbilled Metered City, County, Village Usage
■ Unbilled Unmetered Leaks, Breaks, Theft, etc.
■ Water Losses
■ Apparent Losses Meter Inaccuracies, Data Handling, Theft
■ Real Losses Leaks, Breaks
■ Non Revenue Water
■ Water Loss + Unbilled Metered + Unbilled Unmetered
■ Can determine annual cost of apparent and real losses
■ Where does the water come from and go?
■ Water Treatment Plant with High Service Pumps
■ Water Supply – Purchased? Imported?
■ Water Supply – Sold? Exported?
■ Emergency Interconnections – When? How Much?
■ Adjustments to Water Supply – Meter Registration?
■ Water Usage Reports, Data and Loss Calculations
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Case Study - Loveland■ City believed losses were 10% - 12%
■ AWWA M36 process was implemented. Both apparent and real losses were discovered
■ Losses were determined to exceed 30%
■ Apparent losses included improperly installed meters at the well field and unmetered water
■ Real losses included detected line losses
■ With recommended implementation, losses reduced to 14%
City of Loveland Service Area Map
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Water Loss Process■ An example of tools and report generated for Butler County,
Ohio Water Loss Study
■ Summary Report with Recommendations
■ Category Worksheet
■ Water Balance Report
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Butler County Water Summary Report
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Butler County Water Summary Report
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Butler County Water Summary Report
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Butler County Water Category Worksheet
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Butler County Water Category Worksheet
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Butler County Water Balance Summary
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Water Loss - Primary Recommendations■ Water Supply and Customer Meter Maintenance
■ Are meters tested and calibrated as part of a test program?
■ Water Main and Service Branch Maintenance
■ How are outages managed, repairs made, maintenance usage?
■ Every Water Usage Be Metered, at Least Estimated?
■ Temporary, Municipal, Construction, Water Haul, Fire
■ Use monthly billing operations to the extent possible
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Water Loss - Primary Recommendations■ Generate annual water usage reports
from the billing system
■ Service Area
■ Address
■ Branch and meter size
■ Type of usage
■ Meter reading registration
■ Billing date
■ Consider annual water rate increases to fund on-going main, service, and meter maintenance costs
■ Do not allow private mains and unmetered service and fire lines
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Water Loss Recommendations
■ Water Leak Detection Plan
■ Determine actual minimum night rate using demand areas and comparing to expected water usage for area.
■ Uni-Directional flushing programs for cleaning and measuring for leaks
■ Preventative Maintenance
■ Valve exercising and Water Main flushing programs
■ Test all large meters at least every 1 to 2 years. No meter age should be older than 15 to 20 years without regular maintenance or replacement
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Water Loss Recommendations
■ Capital Replacement
■ Review trend analysis of operations, breaks and leak data
■ Develop a prioritized capital plan with an annual replacement rate of at least 1 to 2% of total system mileage each year. Gradual increase in water rates to meet goal.
■ Consider Additional Asset Issues: Inactive Services? Four Inch and less Sized Water Mains? Looping? High Pressures? Street Improvements? Damage Claims? Soils? Vintage?
■ Review billing system data
■ Track data from sales office, through field operations, back to billing offices
■ Use Automated Meter Reading from Wands to Networks
■ Eliminate paper handoffs of data and reporting, use digital
■ Work with fire authorities to estimate fire water usage.
■ Annual customer survey to determine concerns and complaints including water loss
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Summary of Benefits
■ Understand measuring water supply from raw water source, through treatment
■ Improve water data integrity by following the water trail from source to customer tap
■ Identify real water losses and assist with strategies to control leaks and breaks
■ Reduce apparent water losses through customer under charges and meter inefficiencies
■ Better understand the distribution system for improved response to emergencies
■ Truly understand the customer billing system to ensure efficient billing operations
■ Improve water modeling of water system for more accurate water demands and system scenarios
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Summary of Benefits
■ Better maintained system reduces public health threats and property damage due to leaks and breaks
■ Consumers understand that someone cares about the operations and appreciate a fair value
■ Water Loss Study's reduce legal liability due to credible evidence of system review
■ Focused approach for proactive control on leaks
■ Improve regulations and policies to control water loss and lost revenue
■ Obtaining financing is easier, with better terms, from bondholders and grant agencies including:
■ OEPA■ OWDA■ CDBG■ OPWC
Ohio WaterDevelopment Authority
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Questions?
