Transcript GIS AT CCWA - Metropolitan North Georgia Water Planning

Leak Detection at C.C.W.A.
History of C.C.W.A.
CCWA produces up to 39 million gallons a day of
potable water. We have a potable water storage
capacity of 35.6 million gallons stored in 10 ground
and 8 elevated tanks. We also own and maintain 5 raw
water reservoirs that provide raw water to 3 water
production facilities. CCWA serves a population of
260,000 people through a system of distribution
mains 1,265 miles long.
Water Lines in Clayton County
Size
Total Footage
36”
8,100
30”
77,785
24”
170,020
20”
93,877
18”
270
16”
439,165
12”
552,580
10”
43,837
8”
1,878,707
6”
2,822,384
2”
592,208
1”
1,512
¾”
945
•
Total footage in Clayton
County is 6,681,087
•
Total miles of Water Main in
Clayton County is 1,265’
•
Total footage surveyed in
Clayton County is 4,805,312’
•
Total miles surveyed in
Clayton County is 910
•
72% of our water system has
been surveyed
Leak Detection at CCWA
The CCWA Board of Directors and Management Team
began searching for ways to decrease our water loss.
In March of 2000, Leak Detection was implemented.
Non-Revenue Water Loss
March 2000
October 2004
• Non-revenue water loss
was nearing 20%
• Non-revenue water loss is
at 11%
• Leak Detection program
Initiated
• Meter Testing Program
expanded and placed
under direction of the
Maintenance and
Construction Department
Meter Testing & Repair
CLAYTON COUNTY WATER AUTHORITY
3" - 10" METER TEST RECAP SHEET
COMPLETION OF INITIAL TESTING
1999 TOTALS
MONTH
JANUARY
FEBRUARY
MARCH
APRIL
MAY
JUNE
JULY
AUGUST
TOTALS:
YEARLY USAGE
GALLONS
2,193,180,000.00
16,740,000
35,148,000
118,260,000
45,636,000
3,524,000
2,088,000
5,058,000
5,112,000
2,424,746,000.00
POTENTIAL NET GAIN
GALLONS
644,650,185
POTENTIAL NET GAIN
REVENUE
$2,642,065.75
64,740,000
16,190,052
37,672,992
36,932,712
1,288,000
160,620
33,503,556
15,205,692
850,343,809
$265,434.00
$66,379.21
$154,459.27
$151,424.12
$5,280.80
$658.54
$137,364.57
$62,343.34
$3,485,409.60
All 3" and larger meters (270) in our system have been repaired/replaced and tested.
Meter Accuracy
Meter Size
5/8"
3/4"
1"
1 1/2"
2"
3"
4"
6"
8"
10"
Totals
Total Number of Meters
Standard Register
ECR Register
Total
38,871
26,660
65,531
446
589
1,035
582
685
1,267
296
375
671
160
479
639
17
573
590
8
8
16
8
134
142
2
15
17
1
40,391
29,518
69,909
Number of AMR Meters
9,516
343
369
198
231
40
12
56
3
1
10,768
Averaged Meter Accuracy
PD
Turbo
Compound
FireLine
99.10% 99.37% 97.20% 98.97% 98.99%
99.78% 99.77% 101.50% 99.53% 99.57% 100.94%
99.26% 98.01% 97.52% 99.00%
99.82% 99.25% 99.82%
Total
98.73%
100.18%
98.45%
99.63%
99.25%
Our Goal
Our goal was to
develop and maintain
a comprehensive Leak
Detection Program by
surveying the entire
Distribution System.
Starting a Leak Detection Crew
1.
We investigated and demonstrated several
types of Leak Detection Equipment.
2.
After identifying the type of system we needed,
our request was approved by the Clayton
County Water Authority Board of Directors.
3.
We then started a Leak Detection Crew
consisting of two people.
4.
We also added a Repair Crew made up of four
people dedicated to repairing leaks that were
found by the Leak Detection Crew.
Equipment Purchased
•
The system we purchased is the
Flow Metrix Digicorr 98which has
been upgraded to Digicorr III
•
Digital Correlating Loggers
•
Digitized map information (The
entire county’s water system is in
the Digicorr program)
•
Digital Filters
•
Leak Detection Equipment and
Van cost was approximately
$71,000.00
The Digital Difference
Flow Metrix was
able to create
digital images of
both area maps
and detailed
street plans used
by the Clayton
County Water
Authority.
Getting Started
1. Connect both Field
Sensing Units (FSU)
to the Water
Distribution System.
•
FSUs can be
connected to meters,
service lines, fire
hydrants and valves.
•
Just make sure the
connection is good
and solid.
Programming the Computer
2. After everything is
connected it is time to
input the information
in the computer.
•
Enter the pipe material
and diameter.
•
Enter the distance
between the sensors.
•
Then your ready to
start correlation.
The Computer
Leak
3. Once the base and the
FSU radios are linked,
the correlation
process will begin
automatically.
•
The peak that
develops in the
correlation function
indicates a leak.
•
It usually takes
between 1-30 seconds
for a peak to develop.
Z-Corr Digital Correlating Logger
Programming Z-Corr
1.
Pick an area for
deployment
2.
Program and place
loggers on the map
and print work order
3.
Deploy
Deploying Z-Corr
•
Z-Corr is ideally deployed
underground on a valve
operating nut
•
However, it can also be
mounted on any water system
fitting
Picking up Z-Corr and
Downloading Information
•
Once you pick up Z-Corr,
place units back in docking
station and download
information
•
The computer automatically
goes through all the loggers
and finds possible
correlations
•
Once a correlation has been
detected enter the distance
between loggers, pipe length
and pipe diameter
•
The computer will then
automatically give you a
distance and location for the
suspected leak
Formula to Determine
Rates of Leakage
Formula for Circular Orifice
Q = 30.394 x A x P
Formula for Other Opening
Q = 22.796 x A x P
A = Area of Opening in Square Inches
P = Pressure (PSI)
Q = Gallons Per Minute (GPM)
• Some commonly used square roots
55 = 7.4
60 = 7.7
65 = 8.1
70 = 8.4
85 = 9.2
90 = 9.5
95 = 9.7
100 = 10.0
75 = 8.7
Example 6” Main with 1/8” wide beam break at 80 psi
GPM = 30.394 x (3.14 x 6 x 1.25) x 80
30.394 x 2.35 x 8.94 = 638.5 gpm
80 = 8.9
Leaks Discovered
SIZE
FOOTAGE
LEAKS
GALLONS PER YEAR
¾”
98, 581. 1’
90
391, 674, 800
1”
21, 251. 4’
12
76, 211, 900
2”
224, 001. 8’
50
245, 681, 000
6”
2, 165, 462. 5’
19
1, 000, 742, 400
8”
1, 246, 862. 5’
5
345, 844, 800
10”
50, 801. 5’
1
4, 730, 400
12”
189, 550. 8’
1
1, 576, 800
16”
547, 657. 4’
1
10, 512, 000
20”
75, 547. 3’
0
0
24”
185, 596. 1’
0
0
30”
0
0
0
36”
0
0
0
4, 805, 312. 40
179
2, 076, 974, 100
TOTAL
Program to Date
•
Year
•
•
•
•
•
2000
2001
2002
2003
2004
# Leaks Discovered Gallons Recovered
47
48
16
48
26
TOTALS
•
•
•
735,445,800
506,941,200
134,810,700
462,468,000
237,308,400
Production Cost
$1,220,840.03
$927,702.40
$338,374.86
$1,114,547. 88
$688,194.36
March 2000 – October 2004
179 leaks discovered and repaired
2, 076, 974, 100 gallons
$4, 289, 659. 53 in production cost saved
Production per Customer
In 1999 we served 61,200 water customers (including accounts
served by the City of Riverdale) and were producing/purchasing
10.5 billion gallons of potable water per year (171,568
gallons/customer/year).
We currently serve 73,600 water customers and are
producing/purchasing 9.9 billion gallons of potable water per year
(134,510 gallons/customer/year).
This programs success equates to a decreased production
requirement of 5.8 MGD. That un-needed production is equal to
over 50% of the capacity of our Freeman Road Water Production
Facility and will delay Plant Expansions by several years.
Cost of Program
•
Total expended to date including Initial Investment,
Hardware/Software Upgrade, Salaries, and Operating Expenses is
$472,922.00.
•
Projected annual operating costs $96,229.00
•
For every dollar expended we have recovered $9.07 in Production
savings.
Leaks Found
•
We found a total of 179
leaks
•
90 leaks on ¾” water
service lines
•
12 leaks on 1” water service
lines
•
50 leaks on 2” water mains
•
19 leaks on 6” water mains
•
5 leaks on 8” water mains
•
1 leak on 10” water mains
•
1 leak on 12” water mains
•
1 leak on 16” water mains
Leaks Found
6” Beam Break = 160 GPM
¾”bypass on 8” Fire Line = 30
GPM
Leaks Found
6” Beam Break =508 GPM
¾” Galvanized Service Line = 9 GPM
Leaks Found
¾” Copper Service Line = 9 GPM
6” A.C. Pipe Split = 160 GPM
Conclusion
The purpose of this presentation was to provide
an information resource supporting the
development of a Leak Detection Program and
demonstrating the new technologies and
management concepts to cost effectively reduce
leakage to minimize your water/monetary losses.
Please call Jeff Jones, CCWA Leak Detection
Foreman, at 770-960-3612 for more information.