1. WATER AUDIT DATA COLLECTION AND VALIDATION USING THE Awwa free water audit software© George KUNKEL, P.E. WATER EFFICIENCY PROGRAM MANAGER PHILADELPHIA Water DEPARTMENT
11/29/2012

2. Compiling the Annual IWA/AWWA Water Audit
Focus of this Section
The AWWA Free Water Audit Software©
Data collection
Data gradings
Data Validation
AWWA Compiler Software©
AWWA North American Validated Dataset
Regions requiring water audit data collection for large numbers of water utilities
California Urban Water Conservation Council – as part of Best Management Practice 1.0 for Utility Operations Programs, section 1.2 Water Loss Control
Texas: Texas Water Development Board (2005)
TWDB-specific form; similar to AWWA Free Water Audit Software©
Georgia: Under the Water Stewardship Act (2012); initial data is being analyzed
Delaware River Basin Commission: launching in 2013
These efforts offer a frame of reference and opportunity for learning further about the water audit data collection process

3. IWA/AWWA Water Audit Method: Water Balance
Imported
Own
Sources
Total
System
Input
( allow
for
known
errors )
(allow
errors)
Supplied
Exported
Losses
Authorized
Consumption
Authorized
Consumption
Billed
Authorized
Consumption
Revenue
Water
Billed Water Exported
Billed Metered Consumption
Billed Unmetered Consumption
Unbilled
Authorized
Consumption
Non-
Revenue
Water
Unbilled Metered Consumption
Unbilled Unmetered Consumption
Water
Losses
Apparent
Losses
Unauthorized Consumption
Customer Metering Inaccuracies
Systematic Data Handling Error
Real
Losses
Leakage on Mains
Leakage on Service Lines
Leakage & Overflows at Storage

4. Best Practice Tools for Water Loss Control
AWWA M36 Publication
Water Audits and Loss Control Programs (2009), 3rd Edition features the IWA/AWWA Water Audit Methodology
AWWA Water Loss Control Committee’s Free Water Audit Software©
Current version is 4.2 in English and French languages
Includes data grading capability
Companion “Compiler” Software
Water Research Foundation Reports
Project 4372: Leakage Component Analysis is currently being executed
Textbooks
- type “water loss control” in search box; select first item in list

5. Reporting Worksheet

7. Grading “Volume from own Sources” quantity
WATER SUPPLIED
<< Enter grading in column 'E'
Volume from own sources: 7
94,
Million gallons (US)/yr (MG/Yr)
Master meter error adjustment (enter positive value): 10 2,
over-registered
Water imported:
n/a
0.000
MG/Yr
Water exported: 7,
WATER SUPPLIED:
84, ? ? ?
Data Grading Criteria for “Volume from own Sources”

8. Grading “Master Meter Error Adjustment” quantity
WATER SUPPLIED
<< Enter grading in column 'E'
Volume from own sources: 7
94,
Million gallons (US)/yr (MG/Yr)
Master meter error adjustment (enter positive value): 10 2,
over-registered
Water imported:
n/a
0.000
MG/Yr
Water exported: 7,
WATER SUPPLIED:
84, ? ? ?
Data Grading Criteria for “Master Meter Error Adjustment”

9. The Grading Matrix – grading data and seeking improved data validity

10. AWWA Free Water Audit Software© Grading Matrix Guidance on Use of Water Audit Data

11. Water Audit – Keys to Reliable Data Collection
Steps to set procedures for reliable water audit data collection
Set reliable inhouse procedures
Watch for “flagged” data in the AWWA Free Water Audit Software©
Built-in checks in the software help alert the auditor to data issues
Water audit components to watch:
Production Metering – “Volume from Own Sources” and “Water Imported” quantities
Exported water quantity
Unbilled authorized consumption
Systematic Data Handling Error
Length of Private Pipe
Annual Cost of Operating the Water System
Be objective in grading all components – refer to the grading matrix criteria

12. Data Collection – Setting Reliable Inhouse Data Collection Procedures
When launching the auditing process, it is important to bring together the utility staff most familiar with:
Production Metering
Customer Metering
Customer Billing
Distribution System operations & leak detection
Mapping/Geographical Information Systems
Hydraulic Modeling (if available)
Strive to have the knowledgeable people participating- the water audit is not an administrative task (Don’t assign water audit data collection to the secretary)

13. Data Collection Integrity – Avoid Reporting Bad Data
Software features “flags” for bad data
It’s impossible for a utility to bill more water than they supply
If this occurs, the software gives a red “flag” to alert the auditor to recheck the data inputs
Unfortunately, some utilities are submitting water audits with such flagged data
Suggestion:
The lead person of the water utility should sign-off on the water audit when it is submitted to the reporting agency.

14. Accurately Quantifying “Water Supplied”
This is the most important quantity in the Water Audit!
It is the largest number in the Water Audit
Any error in this value carries throughout the entire Water Audit
Several steps exist to reliably quantify the “water supplied” quantity
Source water, imported water and exported water should always be metered
Ideally, these meters should be the continuously recording type ideally linked to a Supervisory control and data acquisition (SCADA) System
If meters are not linked to a SCADA System, then data should be collected as frequently as possible, at least weekly
If meters are not continuously recording type, and are read infrequently, plan to upgrade the metering installation as soon as possible

15. Accurately Quantifying “Water Supplied”
Testing Approach
Volumetric Meter Test
Comparative Meter Test

16. Accurately Quantifying “Water Supplied”
Meters should be regularly verified for accuracy
Large meters can be compared with an inline insertion or strap-on meter measuring flow downstream of the primary meter
Make certain that the temporary metering location is representative and accurate
Strive for minimum 24-hr period if using this method
Philadelphia Water Department conducts over 50 verifications each year in this manner
Smaller meters might be tested using field test apparatus as is conducted on large customer meters
Document/store the inaccuracy values to serve as a basis for data adjustments
Recognize that calibration of the related instrumentation (differential pressure transmitters) does not verify the flow measuring capability of the meter!
Insertion pito rod measuring and recording flow

17. Accurately Quantifying “Water Supplied”
Meters should be recalibrated, repaired or replaced regularly to maintain reliable performance
New, current-technology meters should replace dated or defective meters
Permanently installed insertion type meters can be a less costly means of establishing or renewing reliable metering
Refer to AWWA M33 guidance manual “Flowmeters in Water Supply” for information on meter selection
Many dated meters exist throughout the North American water industry
Magnetic Flow meter replacement on 48-inch untreated water line 2008 in Philadelphia

18. Accurately Quantifying “Water Supplied”
Regularly determine Master Meter Error Adjustment
Data should be reviewed at least weekly, but ideally, each business day, for trends/anomalies
Balance flows to account for storage level changes and district water transfers
Adjust for recorded inaccuracy levels of given meters
Adjustments due to data error
Adjustments due to data gaps
Aggregate master meter error is:
Added if source meter under-registration exists
Subtracted if source meter over-registration exists
16-inch turbine meter on wholesale account being verified via inline pito rod

19. Know Your Production Metering Configuration
By monitoring the differences (A-B, B-C, A-C) on a daily basis, anomalies are detected when these relative differences begin to stray from typical trends

20. Adjusting for Data Gaps
Production flow data should be reviewed on a frequent basis to monitor for data gaps
Gaps occur due to:
Unplanned interruption: lightning strike, power failure
Planned interruption: instrumentation calibration
Gaps in water flow data should be quantified and added back to the daily total

21. Assembling Data for the Annual Water Audit
SCADA “A” history: raw data from the field
SCADA “B” history: corrected, final data

22. Data Collection – Exported Water Quantity
Extract the Exported Water Quantity from the Customer Billing System
Don’t “double-count” this quantity by including it additionally in “Billed Authorized Consumption”
The “Exported Water” quantity is a separate item in the water audit because:
It stems from one or more bulk quantity measurements
It is typically billed under a different billing rate than retail customer sales

23. Data Collection – Unbilled Authorized Consumption
Unbilled Authorized Consumption components metered and/or un- metered consumption, e.g.:
Street cleaning
Mains flushing
Fire fighting
Generally small portion of the “water supplied” volume
Don’t spend lots of time on quantify this value if data is not available
Instead, use the default value for “Unbilled Unmetered Consumption”
Improve data validity over time

24. Data Collection – Systematic Data Handling Error
Deals with the customer meter reading and billing processes
This quantity is perhaps the least understood component of apparent loss
Like unauthorized consumption, every water utility has some amount of systematic data handling error, even if it is a low amount
Important to include at least a minimal volume here – don’t leave this volume at zero. The software does not provide a default value for this component
Detailed auditing of billing records will likely lead to sources of this error and quantification of a value

25. Length of Private Pipe
Can be difficult to understand the concept around this parameter, however:
If customer water meters are typically located in a meter pit outside of the customer premises then this value is zero

26. Data Collection – Financial Data: Cost to Operate the System
Includes costs for drinking water operations only – do not include sewer, stormwater or other costs in this quantity
Typically includes power costs to treat and convey water, chemical and other costs at the water treatment plant, staff costs for drinking water only
May include liability costs related to water events (ex: damage from main breaks)
Don’t include depreciation effects

27. Water Audit Data Collection Initiative 2011 & 2012
Effort of the AWWA Water Loss Control Committee
Goal: create a dataset of validated water utility water audit data (IWA/AWWA Method)
Steps:
Enlist water utilities that are motivated to employ best practices
Gather the water audit data via AWWA Free Water Audit Software©
Conduct a minute telephone interview w/ key utility personnel
Post the utility data on the AWWA website as examples of best practice adopters and their data
Primary Focus: “Validation” of data; key on data grading values

28. AWWA Free Water Audit Software© - Companion “Compiler” Software
EXCEL spreadsheet tool that allows data from multiple water audits to be “compiled” into one spreadsheet
Date can be copied to user’s EXCEL files
Available for free download from AWWA website

29. Water Audit Data Collection Initiative 2011
2011 Data Collection notables:
21 water utilities (19 USA, 2 Canada)
17 systems over 10,000 connections; 4 systems under 10,000 connections
Observations from the data:
Validation results: ave data validity score dropped from 78 to 74 after validation
Wide variation in production costs: $183/mg (KY) to $2,110/mg (TN) – ave. $726/mg
Customer retail costs: ave. $4.57/1,000 gals Range $1.11 to $8.38
Ave apparent losses: 15 gal/connection/day
Ave real losses: 63 gal/connection/day

30. AWWA Water Audit Compiler© features readily displayed graphs – Apparent Losses (gal/conn/day)
Apparent (non-physical) losses in gal/service connection/day: good for performance tracking

31. AWWA Water Audit Compiler© features readily displayed graphs – Real Losses (gal/conn/day)
Real (leakage) losses in gal/service connection/day: good for performance tracking

32. use this indicator in the form of gallons/mile of pipeline/day)
Water Audit Data Collection Initiative 2011
This is the BEST Performance Indicator for monitoring progress within an individual water utility.
(Note: utilities with very low connection densities and meters located after the curb stop
use this indicator in the form of gallons/mile of pipeline/day)

33. Summary – key steps for valid data collection
Standardized Water Audit Data Collection is occurring across the United States
The data collection process is still relatively young but is maturing
Water utilities should assign knowledgeable staff members from all functional areas to assemble the water audit
The lead person of the water utility should review the water audit before it is submitted to the reporting agency
Valid data is needed to accurately represent the water efficiency of the water utility and guide improvements

34. On to the Next Section