PNWS AWWA Conference Water Audit Workshop 2018
In Introductions Mike Dexel Reinhard Sturm Lucy Andrews DOH WSO WSO
In Introductions Name City/Agency Position Familiarity with water auditing and water loss control? Week’s highlight!
Agenda • Setting the scene • American Water Works Association water audit methodology • Water audit validation • Washington pilot program • Future water loss control in Washington
Today’s Goals 1. Learn AWWA water audit methodology , especially as it applies to your system and Washington regulation 2. Compare results achieved through AWWA and other water loss estimation methodologies 3. Plan next steps toward improved data and water loss management, particularly with a focus on cost justification
Water Loss Reporting in the US
Water Audit Goals: • Estimate volumes and values of real loss and apparent loss • Use a standardized methodology • Consider the accuracy and quality of data sources • Interpret performance with performance indicators
The Water Balance Billed Revenue Consumption Water Authorized Consumption Unbilled Consumption Water Supplied Apparent Non-Revenue 6053 25 Loss Water Water Losses Real Loss
Water Supplied Billed Metered Consumption Billed Authorized Revenue 75 Consumption Water Billed Unmetered Consumption Authorized 80 80 5 Consumption Unbilled Metered Consumption Unbilled Authorized 90 8 Consumption Unbilled Unmetered Consumption 10 Water Supplied 2 100 Unauthorized Consumption Non-Revenue 1 Water Apparent Losses Customer Metering Inaccuracies 20 Water Losses 3 1 10 Systematic Data Handling Errors 1 Real Losses 7
Water Supplied – Volumes Volume from Own Sources Water Imported Water Exported Did we treat the water to potable Did we buy potable water Is the export delivered from the standards? someone else treated? distribution system or point of treatment? Did we import raw water from someone else?
Water Supplied – Audit Boundaries Raw Water Meter Potable Treatment Plant Well Meters Intertie Insertion Potable Finished Water SC-1 Meter Intertie Meter SC-2A SC-3 Distribution System SC-4A SC-5A Lake Fill Potable Intertie Storage
Water Supplied – Audit Boundaries Raw Water Meter Potable Treatment Plant Intertie 10,921.1 AF 4,148.7 AF Insertion Potable Finished Water SC-1 Meter Intertie Meter 275.9 AF 8,032.9 AF SC-2A 938.5 AF Distribution System 2,784.8 AF SC-3 Net recorded input: 28,023.9 AF Volume from Own Sources 279.4 AF SC-4A Water Imported -1,106.5 AF -80.4 AF 26.2 AF 1,803.3 AF Water Exported SC-5A Lake Fill Changes in Storage Potable Intertie Storage Export
Water Supplied – Data Chain 4 – 20 mA Digital Signal Or Pulse SCADA System Secondary Electronics* Measurement Element *Calibration
Water Supplied – Meter Testing Impact of System Input Meter Error 120 Comparative instrument test • Ultrasonic 100 • Insertion Volume (MG) • Pitot tube 80 100% increase in loss assessment 60 Reference volume test • 40 Tank fill up • Tank drawdown 20 0 Base Case Production Meters are 5% Under-Reading Authorized Consumption Water Loss
Authorized Consumption Billed Metered Consumption Billed Authorized Revenue 75 Consumption Water Billed Unmetered Consumption Authorized 80 80 5 Consumption Unbilled Metered Consumption Unbilled Authorized 90 8 Consumption Unbilled Unmetered Consumption 10 Water Supplied 2 100 Unauthorized Consumption Non-Revenue 1 Water Apparent Losses Customer Metering Inaccuracies 20 Water Losses 3 1 10 Systematic Data Handling Errors 1 Real Losses 7
Authorized Consumption Billed Metered Billed Unmetered Consumption Consumption Unbilled Metered Unbilled Unmetered Consumption Consumption
Authorized Consumption District facility use Tank overflow Billed? Well water lubrication Unbilled? Firefighting Main breaks Metered? Flat-rate condominiums Unmetered? Parks department irrigation Single-family indoor use
Billed Metered Authorized Consumption Duplicates Negative One summary Missing Reads number Data Zero Reads Adjustments Outliers A lot of data
Water Loss Billed Metered Consumption Billed Authorized Revenue 75 Consumption Water Billed Unmetered Consumption Authorized 80 80 5 Consumption Unbilled Metered Consumption Unbilled Authorized 90 8 Consumption Unbilled Unmetered Consumption 10 Water Supplied 2 100 Unauthorized Consumption Non-Revenue 1 Water Apparent Losses Customer Metering Inaccuracies 20 Water Losses 3 1 10 Systematic Data Handling Errors 1 Real Losses 7
Water Loss Apparent Losses Real Losses vs.
Apparent Loss – Categories read.p read.r 62549 62549 62549 00 62549 00 62549 00 62549 62549 62549 62549 Unauthorized Consumption Metering Inaccuracy Data Handling Errors Theft! Customer meter under Reporting or other clerical registration errors during the handling of meter reading data
Apparent Loss – Value 90% Customer Meter Accuracy 100% Customer Meter Accuracy 62549 00 62549 00 Service Charge: $20 Service Charge: $20 Volume of Use: 9 CCF Volume of Use: 10 CCF Variable Charge: $3.00 x 9 = $27.00 Variable Charge: $3.00 x 10 = $30.00
Real Loss – Value Purchase Costs Real Loss Electricity for Pumping 62549 00 Chemicals Authorized Consumption
Unavoidable Annual Real Loss Economically Recoverable The AWWA audit software models the technical minimum Potentially volume of real loss based on Recoverable system infrastructure data . Unavoidable Current Annual Real Losses Economic Level of Real Losses Unavoidable Annual Real Losses
System In Infrastructure Data System Average Count of Service Connections Miles of Mains Pressure The average pressure The miles of mains The number of active across the full potable including fire hydrant and inactive service distribution system. laterals. connections.
Cost Data Total Annual Operating Cost – everything you spend in a year O&M budget capital improvements Customer Retail Unit Cost – weighted average sales commodity rate no fixed charges consider all classes and tiers Variable Production Cost – value of leakage cost to acquire, treat, and distribute water any other costs of leakage?
Performance In Indicators Volumes Values Validity Real & Apparent Losses Cost of Real Losses Data Validity Grades & Score Cost of Apparent Losses Real & Apparent Losses per Connection per Day Infrastructure Leakage Index
No Percentages! Year 1 Year 2 Water Supplied: 1000 Water Supplied: 800 Authorized Consumption: 900 Authorized Consumption: 700 Water Loss: 100 Water Loss: 100 Water Loss: 10% Water Loss: 14%
AWWA Free Water Audit Software ? Click to access definition Water Audit Report for: Northern San Leandro Combined Water Sewer Storm Utility District (0007900) + Click to add a comment Reporting Year: 2013 1/2013 - 12/2013 Please enter data in the white cells below. Where available, metered values should be used; if metered values are unavailable please estimate a value. Indicate your confidence in the accuracy of the input data by grading each component (n/a or 1-10) using the drop-down list to the left of the input cell. Hover the mouse over the cell to obtain a description of the grades All volumes to be entered as: MILLION GALLONS (US) PER YEAR To select the correct data grading for each input, determine the highest grade where the utility meets or exceeds all criteria for that grade and all grades below it. Master Meter Error Adjustments <----------- Enter grading in column 'E' and 'J' ----------> WATER SUPPLIED Pcnt: Value: Volume from own sources: 5 1,000.000 MG/Yr 1 100.000 + ? + ? MG/Yr 100.000 Water imported: + ? MG/Yr + ? MG/Yr Water exported: 100.000 MG/Yr 25.000 MG/Yr + ? 1 9 + ? Enter negative % or value for under-registration WATER SUPPLIED: 825.000 Enter positive % or value for over-registration MG/Yr . AUTHORIZED CONSUMPTION Click here: ? Billed metered: + ? 8 700.000 MG/Yr for help using option buttons below Billed unmetered: + ? 9 50.000 MG/Yr Unbilled metered: + Pcnt: Value: ? MG/Yr + ? Unbilled unmetered: 9 10.313 MG/Yr 1.25% 1.000 MG/Yr 24061 Default option selected for Unbilled unmetered - a grading of 5 is applied but not displayed Use buttons to select AUTHORIZED CONSUMPTION: 760.313 ? MG/Yr percentage of water supplied OR
AWWA Free Water Audit Software
Data Validity Grades Data validity grades (DVGs) document utility practices of: • Data collection • Data review • Instrument maintenance Each audit input is assigned a DVG between 1 and 10 based on criteria DVG criteria are predominantly qualitative DVGs are NOT a measure of accuracy!
Data Validity Grades Meet all criteria at a grade for that grade to apply or drop to a lower grade
Validation Water audit validation aims to: • Identify and correct errors • Evaluate and communicate uncertainty Level 1 – interview Level 2 – deep data review Level 3 – new data from the field
Level 1 Validation Goals: • Confirm accurate interpretation and application of methodology • Identify and correct evident errors • Select appropriate data validity grades
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