HomeMy WebLinkAbout6 - Update Benchmarking Report
CITY OF BOULDER
WATER RESOURCES ADVISORY BOARD
AGENDA ITEM
MEETING DATE: June 15, 2009
AGENDA TITLE: Updated Benchmarking Report
PRESENTER: Bob Harber , Utilities Planning and Project Management Coordinator
EXECUTIVE SUMMARY:
The attached updated benchmarking report is presented for discussion as requested by the
WRAB on May 18, 2009. This report presents performance indicator values for the city
of Boulder as calculated using data from 2008. A running average of each indicator from
previous years (2005-2007) is also presented for comparison.
STAFF RECOMMENDATION: None
BOARD AND COMMISSION FEEDBACK: None to date
PUBLIC FEEDBACK: None to date
ANALYSIS:
Please refer the attached 2008 benchmarking report for a complete summary of the
benchmarking results.
The indicators are designed to help participating utilities improve their operational
efficiency and effectiveness. AWWA has continued to publish annual reports which
summarize survey data from an increasing number of participating utilities. The current
publication used for comparison purposes is the 2007 AWWA Benchmarking Report
which contains data collected from nearly 350 utilities.
The following provides a discussion of selected performance indicators whose values
vary significantly from previous years:
1) Employee Health and Safety Severity Rate
This indicator is calculated as the total number of workdays missed by all employees due
to work-related injury or sickness divided by the total hours worked by all employees in a
given year. The total number of workdays missed is approximated as total hours missed
divided by 8 hours per workday. The 2008 value of this indicator is substantially lower
than the average of previous years (6.8 compared to 56.0). This is due to year-to-year
fluctuations in the total hours missed by all employees. From 2005 to 2008, the total
AGENDA ITEM # 6 PAGE 1
hours missed by all employees was 717, 934, 30, and 61, respectively. Thus, the data
from 2005 and 2006 are responsible for the high average compared to 2008.
Initially, it was suspected that a policy change may have been implemented between 2006
and 2007 that limited the way in which injury time-off was used. However, inspection of
records indicated that the high values in 2005 and 2006 were due to two or three
individuals who received single injuries that kept them away from work for a month or
more (i.e. shoulder injury, broken leg, etc.). A single injury of this nature can represent
an enormous percentage of the total hours missed due to work-related injury or sickness.
Thus, it is expected that this indicator will likely experience wide fluctuations from year
to year as a result of a few, isolated injuries.
2) Training Hours per Employee
This indicator has only been tracked in 2007 and 2008. Between 2007 and 2008, most
workgroups under the water and wastewater funds completed the same number of
training hours. The one exception was the maintenance group. In 2007, the maintenance
group reported 2,425 total training hours. In 2008, this number was 504 hours; a
decrease of 1,921 hours. However, this apparent decrease does not necessarily imply a
true decrease in training hours. Rather, a conscious decision was made in 2008 to record
only training hours which are considered routine monthly training and ignore non-routine
training hours. This method of recording training hours may provide a more fundamental
and basic assessment of training efforts within the Utilities Division. However, a final
decision as to how this indicator will be tracked in the future has not yet been made.
4) Technical Quality Complaints
In 2008, the Technical Quality Complaints indicator, measured as complaints per 1,000
customers, was roughly 60% higher than the running average dating back to 2005. This
indicator primarily reflects the total number of water quality complaints received each
year. Dating back to 1992, the city of Boulder has received an average of 170 WQ
complaints per year (see figure below). However, this value has been as high as 380 and
as low as 70. Total complaints per year for the four years this indicator has been tracked
are 184, 204, 127, and 268. These values are well within the range of historic values.
Although 2008 did experience more complaints than previous years, this value is not
unusually high.
AGENDA ITEM # 6 PAGE 2
Type of Complaint, 1992-2008
Count of Complaint
400
350
300
250
Complaint
0 Taste/odor
° 200 13 Other (describe)
U
❑ Dirty/Rusty
150
100
50
0
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
Year
Year
6c) Cost of Sewer Based on Monthly Residential Sewer Use of 7,500 Gallons
The cost of sewer service for 7,500 gallons per month in 2008 was roughly 14% higher
than the running average dating back to 2005, indicating that the sewer rate has been
increased by a total of 14%. Over the past two years, the rate has increased by roughly
5% per year. However, between 2005 and 2006 (2005 being the first year this indicator
was tracked) the rate increased by 20%. This rate increase was implemented in order to
fund the improvement projects at the wastewater treatment plant. A similar increase was
also implemented between 2004 and 2005; however this increase superseded the
inaugural benchmarking study and is not reflected in the running average.
7) Debt Ratio
In 2008, the city of Boulder's debt ratio (liabilities divided by assets) was 20% lower than
the running average dating back to 2005. In fact, the debt ratio has been decreasing every
year since the benchmarking process began. During this period, the total value of all
water and wastewater assets has remained relatively constant (see figure below).
However, total liabilities have been steadily decreasing. In essence, the city has been
making a conscious effort to pay-down the debt in recent years.
AGENDA ITEM # 6 PAGE 3
WaterNVastewater Assets & Liabilities
$400,000,000
$350,000,000
$300,000,000 f
$250,000,000
$200,000,000
$150,000,000
$100,000,000
$50,000,000
2005 2006 2007 2008
o Total Liabilities ■ Total Assets
8a-d) System Renewal/Replacement Rates
Each of these indicators measures the total annual expenditures (10-yr average) for
infrastructure renewal/replacement as a percentage of what we think we should be
spending annually. Since 2005, these percentages have been declining (see figure
below). There are two possible explanations for these declines. 1) We're spending less
money on infrastructure renewal each year. 2) The total value of our infrastructure assets
has increased. A combination of these two explanations is also a possibility.
AGENDA ITEM # 6 PAGE 4
Infrastructure Renewal Rates (2005 -2008)
20.0%
18.0%
16.0%
14.0%
~ 12.0%
io 10.0%
8.0%
m
6.0%
4.0%
2.0%
0.0%
Water Pipe Water Wastewater Pipe Wastewater
Treatment/Pumping Treatment/Pumping
Asset Category
❑ 2005 ■ 2006 ❑ 2007 ❑ 2008
The following figures (accompanied by discussion) show the actual expenditures and
theoretical annual investments (what we think we should be spending) for each asset
category.
Water Pipe
$30,000,000
$25,000,000
$20,000,000
$15,000,000
$10,000,000
$5,000,000
2005 2006 2007 2008
❑ Actual Expenditures ■ Theoretical Investment
AGENDA ITEM # 6 PAGE 5
As seen above, we have been spending a consistent amount of money each year on
replacement of water pipe. However, the value of these pipes has been monotonically
increasing. This is expected, as we update the value of all our assets each year using the
ENR CCI index. However, the figure above shows a sharp increase in asset value
between 2006 and 2007. This coincides with the decision by the Utilities Division to
reevaluate all underground pipe assets. HDR Engineering Inc. was contracted to develop
new cost estimates for full replacement of water and sewer pipe. The result was a net
increase in cost.
Water Treatment/Pumping
$30,000,000
$25,000,000
$20,000,000
$15,000,000
$10,000,000
$5,000,000
2005 2006 2007 2008
❑ Actual Expenditures ■ Theoretical Investment
Similar to expenditures for replacement of water pipe, expenditures for renewal of
treatment and pumping facilities have remained steady over the past four years. The total
value of treatment and pumping assets, however, has been increasing over the same
period of time. This is due to the fact that asset values are updated annually using the
ENR CCI index.
AGENDA ITEM # 6 PAGE 6
Wastewater Pipe
$16,000,000
$14,000,000
$12,000,000
$10,000,000
$8,000,000
$6,000,000
$4,000,000
$2,000,000
2005 2006 2007 2008
❑ Actual Expenditures ■ Theoretical Investment
The renewal rate for wastewater collection pipe exhibits an identical trend to the renewal
rate for water distribution pipe. Again, this is a result of the 2006-2007 asset
reevaluations for underground pipes.
Wastewater Treatment/Pumping
$35,000,000
$30,000,000
$25,000,000
$20,000,000
$15,000,000
$10,000,000
$5,000,000
2005 2006 2007 2008
❑ Actual Expenditures ■ Theoretical Investment
AGENDA ITEM # 6 PAGE 7
The total value of wastewater treatment and pumping assets has also been increasing over
the past four years due to updating costs with the ENR CCI index. However, the sharp
increase in value between 2007 and 2008 is due to the completion of the recent
improvement projects at the wastewater treatment plant. These projects, however, have a
lesser impact on the total annual expenditures because annual expenditures are computed
as a ten-year average for the purposes of this benchmarking study.
Note: In early 2009, two studies were performed in-house to develop 20-year CIP
budgets for renewal and replacement of water mains and sanitary sewer infrastructure.
These studies have shown that the city of Boulder is likely meeting a higher percentage
of its annual needs, for these two asset classes, than previously thought. These studies
will likely be used for future evaluation of the renewal/replacement rate indicator. Thus,
the values of these indicators are likely to increase from less than 10% to greater than
50% in future benchmarking studies.
11) Distribution System Water Loss
Distribution system water loss is a measure of the annual percentage of treated water
which can not be accounted for. The total volume of treated water produced annually is
measured through metering at the exits of both treatment plants. This volume is then
compared to the total volume reported at all customer meters, city meters/irrigation, and
any other quantifiable allocations (such as system flushing). The difference is the total
loss. In 2008, system loss was measured at 6.4%, which is less than the running average
of 8.4%. Since 2005, system loss has never been higher than 9.1
Variations in estimated water loss from year to year could be the result of actual losses or
inaccuracies in metering. Water loss in the city's system is known to occur through three
primary mechanisms. 1) Leaky pipes in lower pressure zones which are not readily
detectible (as apposed to high-pressure catastrophic failures), 2) Leaky concrete tanks
(Chautauqua and Maxwell), and 3) evaporative losses in the three concrete tanks. On the
metering side, there have been known issues with the Boulder Reservoir Plant effluent
meter which, until recently, had produced inaccurate data due to clogged pressure tubes.
Customer billing meters are also known to provide consistently low readings when they
are in need of maintenance. However, the city's Meter Shop readily services meters in an
effort to keep the vast majority functioning properly.
Ultimately, fluctuations in estimated water loss from year to year between 5% and 10%
represent an acceptable degree of variability given all the uncertainties and sources of
error. Although the 6.4% measured in 2008 was lower than previous years, it is unlikely
that this represents a trend of any sort.
AGENDA ITEM # 6 PAGE 8
13a-c) Operations and Maintenance Costs (water system)
In 2008, total O&M costs per customer account (Indicator 13a) stayed relatively stable
compared to previous years (See figure below). In addition, the ratio O&M costs directly
attributed to water treatment to the total volume of treated water (Indicator 13c) stayed
relatively stable. However, the ratio of total O&M costs to the total volume of treated
water (Indicator 13b) was noticeably higher than the average dating back to 2005. As
seen in the figure below, a sudden increase in this ratio occurred between 2006 and 2007.
This is primarily due to a reduction in the total volume of treated water produced
annually. Between 2005 and 2008, the city of Boulder produced total volumes of treated
water of 6,325 MG, 6,852 MG, 6,129 MG, and 6,173 MG, respectively. Thus, while
total O&M cost have remained relatively stable, the ratio of total O&M costs to total
volume of treated water was higher in 2007 and 2008. This also explains why Indicator
13c remained relatively stable. Since 13c only accounts for O&M costs directly
attributed to water treatment, the indicator did not fluctuate with changes in the total
produced volume of treated water.
O&M Costs for Water Distribution
$2,500
$2,000
$1,500
$1,000
$500
2005 2006 2007 2008
❑ O&M Cost per Account ■ O&M Cost per MG ❑ O&M Cost of Treatment per MG
AGENDA ITEM # 6 PAGE 9
15) Sewer Overflow Rate
Between 2005 and 2008, the city of Boulder has experienced 12, 12, 2, and 19 city-
caused sanitary sewer overflows (SSOs) annually. The low value of 2 SSOs in 2007 is
keeping the running-average low compared to 2008's value of 19 SSOs, which appears to
be more in-line with the 12 SSOs experienced in 2005 and 2006. Thus, 2007, not 2008,
represents a deviation from normal performance. The data from 2007 was reviewed and
double-checked to rule-out the possibility of a calculation error. The data was found to be
accurate.
17) Wastewater Treatment Effectiveness Rate
Since 2005, the city of Boulder's wastewater treatment plant (WWTP) has experienced
anywhere from 1 to 5 days per year during which effluent standards were not met. While
2008 experienced 5 non-compliance days, the average of the previous three years was
2.3. Although 5 discharge violations still represent a high level of treatment
performance, a description of each violation in 2008 is warranted.
1. March 6, 2008 - Effluent pH measured at 6.4 (Discharge permit requires that
effluent pH remain between 6.5 and 9.0).
2. March 20, 2008 - Concentration of copper in effluent measured at 50.0
micrograms per liter (Discharge permit requires that effluent concentration shall
not exceed 35.2 micrograms per liter).
3. March 26, 2008 - Concentration of copper in effluent measured at 57.7
micrograms per liter.
4. March 31, 2008 - Concentration of copper in effluent measured at 66.0
micrograms per liter.
5. April 10, 2008 - Concentration of copper in effluent measured at 56.3 micrograms
per liter.
During a 20-day period between late March and early April, effluent sampling detected 4
copper violations. Due to the close timing of these events, WWTP staff conducted an
investigation into possible causes. The results of this investigation were detailed in a
letter to the Colorado Department of Public Health and Environment; a copy of which is
included with this memo. Although the investigation was unable to determine a
definitive cause for the copper violations, several possibilities were identified and a
return to compliance was demonstrated.
18a-c) Operations and Maintenance Costs (wastewater system)
Total annual O&M costs rose in 2008 due to the higher cost of operating the new
activated sludge treatment process at the city's wastewater treatment plant. Prior to 2008,
O&M costs were relatively stable. This "spike" can be seen in the figure below.
AGENDA ITEM 4 6 PAGE 10
O&M Costs for Wastewater Collection
$2,500
$2,000
$1,500
$1,000
$500
2005 2006 2007 2008
❑ O&M Cost per Account ■ O&M Cost per MG ❑ O&M Cost of Treatment per MG
MATRIX OF OPTIONS:
Not applicable
ATTACHMENTS:
Attachment A - 2008 Benchmarking Report
Attachment B - Memo to CDPHE regarding Copper Exceedances
AGENDA ITEM 4 6 PAGE 11
Attachment A
Benchmarking
Performance Indicators for Water and
Wastewater Utilities
2008
Introduction
In 2005, the American Water Works Association (AWWA) developed a report called
Benchmarking - Performance Indicators for Water and Wastewater Utilities: Survey
Data and Analysis Report (by Angela K. Lafferty and William C. Lauer) to assess the
performance of water and wastewater utilities using a set of identified and tested high-
level performance indicators. The indicators are designed to help participating utilities
improve their operational efficiency and effectiveness. The AWWA Benchmarking
Report provides summary data and comparative analyses of survey data collected from
202 utilities during the years 2003 and 2004. AWWA has continued to publish annual
reports which summarize survey data from an increasing number of participating utilities.
The current publication used for comparison purposes is the 2007 Benchmarking Report
which contains data collected from nearly 350 utilities.
These utilities can be broadly categorized according to three criterion measures:
geographic region, population size, and type (i.e. water, wastewater, or combined). For
the purposes of this study, the city of Boulder is a combined utility in the western region
(roughly the Pacific and Mountain time-zones) serving a population of approximately
100,000 customers. Beginning with data collected from 2005, Boulder has participated
in the AWWA Benchmarking Study on in every year since. Although Boulder did not
participate in the original study (2005 report), several Colorado utilities did. They are as
follows.
■ City of Aurora
■ Eagle River Water & Sanitation District
■ Fort Collins Utilities
■ Pagosa Area Water & Sanitation District
■ Town of Rangely
■ Upper Eagle Regional Water Authority
■ City of Westminster
Although participation in the AWWA Benchmarking Study has increased since 2005,
participation amongst Colorado utilities has declined. Only four utilities from Colorado
are included in the 2007 report.
■ City of Aurora
■ City of Boulder
■ Erie Water Department
■ City of Fountain
Attachment A
Of the 22 total performance indicators included in the survey, the city of Boulder chose to
evaluate 19 which were deemed applicable and attainable.
1) Employee Health and Safety Severity Rate
2) Training Hours per Employee
3) Customer Accounts per Employee (water/wastewater) & Million Gallons per Day
(MGD) Water Delivered/Wastewater Processed per Employee
4) Technical Quality Complaints
5) Disruptions of Water Service
6) Residential Cost of Water/Sewer Service
7) Debt Ratio
8) System Renewal/Replacement Rate
9) Return on Assets
10) Drinking Water Compliance Rate
11) Distribution System Water Loss
12) Water Distribution System Integrity
13) Operations and Maintenance Cost Ratios (water)
14) Planned Maintenance Ratio (water)
15) Sewer Overflow Rate
16) Collection System Integrity
17) Wastewater Treatment Effectiveness Rate
18) Operations and Maintenance Cost Ratios (wastewater)
19) Planned Maintenance Ratio (wastewater)
The remaining three indicators were not evaluated due to a lack of current data that was
easily accessible. They include the following:
■ Organizational Best Practices Index
■ Customer Service Cost per Account
■ Billing Accuracy
Each performance indicator within this report is presented using median-range charts.
AWWA provides summary statistics of industry data which includes the median, 25x1'
percentile, and 75th percentile values. These statistics, which describe the inner 50
percent of the data, are plotted, as vertical bars, for comparison against city of Boulder
data. There are both advantages and disadvantages to this method of data reporting. It is
advantageous in that it illustrates the industry norm for each indicator. Unfortunately, it
lacks the ability to describe absolute high and low values, extreme outliers, or the
underlying distribution of the data. The inherent shortcomings of the median-range charts
were imposed by the survey in an effort to protect utility confidentiality. Also for this
reason, the survey does not provide any correlation between individual data points and
utility names.
This report presents indicator values for the city of Boulder as calculated using data from
2008 as a red line. A running average of each indicator from previous years (2005-2007)
is also presented for comparison purposes as a blue line. In some cases, the blue line is
Attachment A
not visible because it is obscured by the red line indicating there has been very little
change in the performance indicator from previous years. Detailed information regarding
indicator values from previous years can be found in the Public Works Project Tracking
Database.
Performance Indicators
1) Employee Health and Safety Severity Rate - Quantifies the rate of employee days
lost from work due to illness or injury.
Average of Previous Years = 56.0
2008 Data:
■ Total workdays away from work = 7.6
■ Total hours worked by all employees = 222,984.99
■ Rate = 6.8 (days per 200,000 hours worked)
I
Employee Health and Safety Severity Rate
N
L
O
p 250.0
0
0
N 200.0
L
CL 'a Median
N Y 150.0
c~ c CoB Avg
❑ 100.0
CoB 2008
50.0
LU-
0.0 -
Cn 1~1 00 00 00 OO ea et ~~t ti~
e J e a
d z S1 50 `a4 `rte oo' ooh oooho~ 0I pc ~a Q~
0 0 o a Qa
~ooo goo ,~o, ~
Attachment A
2) Training Hours per Employee - Quantifies the formal training hours that the utility
employees are completing.
Average of Previous Years = 36.6
2008 Data:
■ Total qualified training hours for all employees= 3373.5
■ Total FTE's worked by employees during reported period= 134.95
■ Training hours per employee = 25.0
Training Hours Per Employee
aoi 45.0
O 40.0
Q
E 35.0
Ui 30.0
L. Median
a 25.0
20.0 CoB Avg
= 15.0 CoB 2008
a) 10.0
c 5.0
L 0.0
4- 4.
`i3
~ o~ ~oo G ~a Qa
Attachment A
3a) Customer Accounts per Employee (water) - Measures the number of customer
accounts per number of full-time equivalents (FTE's) and considers all water accounts
both inside and outside the city.
Average of Previous Years = 379
2008 Data:
■ # of accounts = 28,340
■ # of FTE's = 75.83
■ Accounts per employee = 374
Customer Accounts per Employee (Water)
900
800
m
W
700
0
E 600 Median
w
soo CoB Avg
0 400 CoB 2008
a
300
200
eyti Jr eye aye o~~ QO ~O & DO ea et `et 5
S1 gp a~ ,ce Off. p~ p~ p~ .p~~ y~a'~ ~a 0~
p p
O O O ~0 a
goo ~o 1°, P`e
Attachment A
3b) Customer Accounts per Employee (wastewater) - Measures the number of
customer accounts per number of full-time equivalents (FTE's) and considers all
wastewater accounts both inside and outside the city.
Average of Previous Years = 469
2008 Data:
■ # of accounts = 27,082
■ # of FTE's = 59.12
■ Accounts per employee = 458
Customer Accounts per Employee (Wastewater)
1000
900
m
800
O
700
Median
W 600
CoB Avg
42
500
CoB 2008
O
v 400
MH
a
300
200
14~
_0 N,
Attachment A
3c) Million Gallons per Day (MGD) Water Delivered per Employee - Measures the
average MGD of water delivered per number of full-time equivalents (FTE's). MGD is
measured at the water treatment plant outlets.
Average of Previous Years = 0.23
2008 Data:
■ MGD delivered = 169
■ # of FTE's = 75.83
■ MGD per employee = 0.22
MGD Water Delivered per Employee
0.60
0.50
as
a 0.40
o Median
a
E 0.30 CoB Avg
w
CoB 2008
C7 0.20
0.10
0.00
\9
ob<
o, P~
Attachment A
3d) Million Gallons per Day (MGD) Wastewater Processed per Employee - Measures
the average MGD of wastewater processed per number of full-time equivalents (FTE's).
MGD is measured at the wastewater treatment plant inlets.
Average of Previous Years = 0.25
2008 Data:
■ MGD processed = 13.3
■ # of FTE's = 59.12
■ MGD per employee = 0.22
MGD Wastewater Processed per Employee
0.45
0.40
0.35
5+ 0.30
c Median
E 0.25 CoB Avg
W 0.20 COB 2008
0.15
0.10
0.05
0.00
ey` or e5` ~5` O0~ ODO Op0 ~O ~~O \c~a ~,~ee ~~ti5
o^' oN- G a5 Qa
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Attachment A
4) Technical Quality Complaints - Measures the total annual number of technical
quality complaints per 1,000 customer accounts. "Technical quality" refers to core
services of the utility and includes water quality, taste, odor, appearance and pressure,
sewage backups and overflows, disruptions of water or sewer service, disruptions of
traffic, and facilities upkeep. Water customer accounts only are used for this indicator to
reflect the fact that the majority of customers maintain both a water and wastewater
account.
Average of Previous Years = 6.1
2008 Data:
■ # of accounts = 28,340 (water only)
■ In 2008, Boulder recorded:
268 water quality complaints
1 noise complaint with respect to wastewater plant's cogeneration facility
1 odor complaint near the wastewater plant
1 water quality complaint regarding wastewater effluent quality in Boulder Creek
■ Rate = 9.6 (complaints per 1,000 customers)
Technical Quality Complaints per 1,000 Customers
35.0
E
E 30.0
O
25.0
v Median
0 20.0
Q -CoB Avg
N 15.0 CoB 2008
10.0
Q
O 5.0
V
0.0
~4- o0`r ~4- 00~. 0°0 000 000
~p"0
y`~s~ ~ ~\G\Q`~
00'` 00~00o G ~m \\Qa
Attachment A
5) Disruptions of Water Service - Measures the number of water outages experienced
by utility customers.
Average of Previous Years
■ Planned disruption rate per 1000 customers (less than 4 hours) = 0.10
■ Planned disruption rate per 1000 customers (4 to 12 hours) = 0.02
■ Planned disruption rate per 1000 customers (more than 12 hours) = 0
■ Unplanned disruption rate per 1000 customers (less than 4 hours) = 0.35
■ Unplanned disruption rate per 1000 customers (4 to 12 hours) = 0.09
■ Unplanned disruption rate per 1000 customers (more than 12 hours) = 0
2008 Data:
■ # of accounts = 28,340 (water only)
■ Linear feet of water line replaced in 2007 = 11,680
■ Planned disruption rate per 1000 customers (less than 4 hours) = 0.082
■ Planned disruption rate per 1000 customers (4 to 12 hours) = 0.021
■ Planned disruption rate per 1000 customers (more than 12 hours) = 0
■ Unplanned disruption rate per 1000 customers (less than 4 hours) = 1.457
■ Unplanned disruption rate per 1000 customers (4 to 12 hours) = 0.364
■ Unplanned disruption rate per 1000 customers (more than 12 hours) = 0.036
Disruptions of Water Service per 1,000 Customers
Planned < 4 hours
30.00
L
E 25.00
0
U 20.00
Q Median
0 15.00 CoB Avg
c`n -CoB 2008
0 10.00
i 5.00
0.00
0'~ r 5~ 5~ o~ ~ o0 00 00 oa ~o~ ~o~ ~5
z e a
0 0 0 0 0 0 a s a~
5 o~r~' ADO ~pp' ^pp' hp' L,~o'
00 00 0&
goo, `o°' ~
Attachment A
Disruptions of Water Service per 1,000 Customers
Planned 4-12 hours
N 7.00
L
E 6.00
0
5.00
U
°0 4.00 Median
C -COB Avg
N 3.00 CoB 2008
c
0 2.00
a
N 1.00
0.00 LU
5~ ~r 5~ 5~ 0 0 o
~o°oo°ooo& a e~
o ooo°NocA f~~e~,a~
K~y oo N P
Disruptions of Water Service per 1,000 Customers
Planned >12 hours
1.60
L
E 1.40
0
N 1.20
U 1.00 Median
0
0 0.80 CoB Avg
0 0.60 CoB 2008
0
Q 0.40
N 0.20
0.00
°
'o°oooo
P
Go y a
00 00 0°° ~ P~Q
Attachment A
Disruptions of Water Service per 1,000 Customers
Unplanned < 4 hours
25.00
N
L
m
0 20.00
N
7
0 15.00 Median
U
0
CoB Avg
0 10.00 CoB 2008
0
5 5.00
L N
0.00
r ey` a~` 00, ocP 000 000 ~p° c~a ati6 e
g o~~ X00 X00 \~~Qa
~ ~ o~ Go~aS Qa~
0 0° 0, P~
Disruptions of Water Service per 1,000 Customers
Unplanned 4-12 hours
12.00
N
L
G7
E 10.00
0
w
N
U 8.00
o Median
0 6.00 CoB Avg
4.00 CoB 2008
0
4a
Q.
` 2.00
N
0.00
J6J00 00 00~ ~ Q
P~
Attachment A
Disruptions of Water Service per 1,000 Customers
Unplanned >12 hours
1.80
L
a~ 1.60
E
0 1.40
U 1.20
° 1.00 Median
C 0.80 -CoB Avg
CoB 2008
c 0.60
n 0.40
~Ln 0.20
0.00 -
-7o°oo°oooQ o ooo°~ocp
Attachment A
6a) Cost of Water Based on Monthly Water Use of 7,500 Gallons - Calculates the
expected water bill amount of a single-family residential customer using 7,500 gallons
per month.
Average of Previous Years = $22.23
2008 Data:
■ Bill amount = $23.83
Cost of Water Based on Monthly
Residential Water Use of 7,500 Gallons
L 40.00
M
75
35.00
30.00
Median
0
25.00
CoB Avg
CoB 2008
p 20.00
M 15.00
L
W+
M 10.00
000 000 ~o za
e yes' \G~Q
Attachment A
6b) Cost of Water Based on Average Residential Water Use - Calculates the average
single-family residential water bill based on all bills issued.
Average of Previous Years = $31.56
2008 Data:
■ Bill amount = $29.01
Cost of Water Based on Average
Residential Water Use
50.00
45.00
m 40.00
L
35.00 Median
M
30.00 CoB Avg
a
25.00 CoB 2008
c
0 20.00
15.00
M
L
10.00
oar eye oa~~ pp~ pp0 ppo ppo ppo boa m~~~ ~~5
5 41eo~r Apo po, Apo, <o'
po po o°p ~ P~Q
Attachment A
6c) Cost of Sewer Based on Monthly Residential Sewer Use of 7,500 Gallons -
Calculates the expected sewer bill amount of a single-family residential customer using
7,500 gallons per month.
Average of Previous Years = $24.47
2008 Data:
■ Bill amount = $27.96
Cost of Sewer Based on Monthly
Residential Sewer Use of 7,500 Gallons
45.00
40.00
d 35.00
a Median
0 30.00
~ CoB Avg
25.00 CoB 2008
L
y- 20.00
m 15.00
L
10.00
tl1 5~ ~r 5~ o~ 00 00 00 0 ~a ~e~
0 0 0 a p
•a~o~r ~cA goo' goo' ~~o' moo`
0 00 0, P~
Attachment A
6d) Cost of Sewer Based on Average Residential Sewer Use - Calculates the average
single-family residential water bill based on all bills issued.
Average of Previous Years = $14.41
2008 Data:
■ Bill amount = $15.62
Cost of Sewer Based on Average
Residential Sewer Use
50.00
45.00
m 40.00
L
3 35.00 Median
to 30.00 CoB Avg
.E 25.00 CoB 2008
c
0 20.00
15.00
ca
10.00
Q ~ey~ oar eye ~~5~ poi opp opo opo ppo ~a a~~~
5 I~sr CO~p~
O~ pp Qati
~~o `poop ,gyp, P\
Attachment A
7) Debt Ratio - Measures the debt ratio as total liabilities divided by total assets.
Combined water and wastewater.
Average of Previous Years = 0.36
2008 Data: (Note: 2008 values are preliminary, un-audited estimates. Audited values will
be available in mid-2009)
■ Total liabilities = $102,164,000
■ Total assets = $344,614,000
■ Debt ratio = 0.30
Debt Ratio
0.600
N
a~
0.500
co
0.400
4 Median
CD
N 0,300
CoB Avg
G
CoB 2008
0.200
0.100
a>
0.000
~y~ o~`r eye ~5` oo~ o00
a 5
°o °o oo° ~ P~Q
Attachment A
8a) System Renewal/Replacement Rate: Water Pipelines (distribution) - Quantifies
the rate at which a utility is meeting its individual yearly need for infrastructure renewal
or replacement for the water distribution system.
Average of Previous Years = 14.7%
2008 Data:
■ Total expenditures = $2,468,432
■ Theoretical investment = $25,977,138
■ Rate = 9.5%
System Renewal/Replacement Rate
Water Distribution
a~
25.0
is
Q 20.0
15.0 Median
Z CoB Avg
10.0 CoB 2008
4- 5.0
O
c
v 0.0
L
CL o o
.
N" goo,
o~ o°Go~~S Qat`
0 0° o P~
~o N
Attachment A
8b) RenewaVReplacement Rate: Water Treatment and Pumping - Quantifies the rate
at which a utility is meeting its individual yearly need for infrastructure renewal or
replacement of water treatment and pumping facilities.
Average of Previous Years = 16.6%
2008 Data:
■ Total expenditures = $3,683,884
■ Theoretical investment = $28,398,449
■ Rate = 13.0%
System Renewal/Replacement Rate
Water Treatment/Pumping
a~
% 30.0
j 25.0
Q
20.0
Median
Z 15.0 COB Avg
= 10.0 CoB 2008
Q
5.0 ■
v 0.0 C
L
m eye °~r °4
~ o~ °o~• G°~m~ Qra~.
Attachment A
8c) Renewal/Replacement Rate: Wastewater pipelines (collection) - Quantifies the
rate at which a utility is meeting its individual yearly need for infrastructure renewal or
replacement of the wastewater collection system.
Average of Previous Years = 11.6%
2008 Data:
■ Total expenditures = $612,670
■ Theoretical investment = $13,655,526
■ Rate = 4.5%
System Renewal/Replacemnt Rate
Wastewater Collection
a~
% 16.0
M
14.0
v
Q 12.0
N
10.0 Median
Z 8.0 CoB Avg
6.0 CoB 2008
Q 4.0
4-
0 2.0
v 0.0
L
CL o~~ o°o a`ot a`e~
o ~ o, P~
Attachment A
8d) System Renewal / Replacement Rate: Wastewater Treatment and Pumping -
Quantifies the rate at which a utility is meeting its individual yearly need for
infrastructure renewal or replacement of wastewater treatment and pumping facilities.
Average of Previous Years = 13.2%
2008 Data:
■ Total expenditures = $1,068,382
■ Theoretical investment = $28,976,381
■ Rate = 3.1
System Renewal/Replacement Rate
Wastewater Treatment/Pumping
a~
30.0
is
j 25.0
a
-p 20.0
Median
Z 15.0 COB Avg
= 10.0 CoB 2008
a
0 5.0
r
c
v 0.0
L
a. oy` °`r o4- ea4- o°o o°o o°(Z) o°o ~a `et `o~
o~~~~y~~a ~a \G.Q~
~ ~ o~ o° G Qat`
4o,
Attachment A
9) Return on Assets - Measures the return on assets (ROA) as net income divided by net
total assets. Includes water and wastewater funds only.
Average of Previous Years = 0.20
2008 Data: (Note: 2008 values are preliminary, un-audited estimates. Audited values will
be available in mid-2009)
■ Net income = $46,125,000
■ Net Total assets = $242,450,000
■ ROA = 0.19
Return on Assets
7.0
N 6.0
.r
as
N 5.0
a
4.0 Median
0
~ 3.0 CoB Avg
a)
E 2.0 CoB 2008
0
= 1.0
.r
as
Z 0.0
-1.0
ems` o3~r~,e~` eae` 00~. oeA 00° 000 000 c~a fie` ame,"
5 a R
00~ 00~ C; day Qm~
10) Drinking Water Compliance Rate - Quantifies the percentage of time each year
that a water utility meets all health-related drinking water requirements. Boulder, in
addition to all reporting utilities, was in 100 percent compliance with health-related
requirements in 2008. The average of previous years is also 100 percent No figure is
required.
Attachment A
11) Distribution System Water Loss - Measures the percentage of produced water that
fails to reach the customers and cannot otherwise be accounted for through authorized
usage. Authorized but unbilled water includes Unidirectional Flushing (UDF) values and
city metered accounts.
Average of Previous Years = 8.4
2008 Data:
■ MG water distributed = 6,173
■ MG water billed = 5,515
■ MG water unbilled but authorized = 260
■ Water loss = 6.4%
i
Distribution System Water Loss
18.0
N 16.0
O
-J 14.0
L
O 12.0
10.0 Median
O CoB Avg
8.0
CoB 2008
6.0
c
v 4.0
L
M 2.0
0.0
Attachment A
12) Water Distribution Integrity - Measures the total number of water pipeline
leaks/breaks per 100 miles of distribution piping.
Average of Previous Years = 16.4
2008 Data:
■ # of leaks/breaks = 86
■ Miles of distribution piping = 451
■ Integrity rate = 19.1 (per 100 miles)
Water Distribution System Integrity
m
.O
140.0
Q
E 120.0
4-
O
Cn 100.0
2 80.0 Median
°o CoB Avg
60.0 CoB 2008
Q
N 40.0
Y
O
L 20.0
Ll I
m
•7 0.0
eye ~~r eye a5~ o o O a et
Attachment A
13a) Operations and Maintenance (O&M) Cost per Account (water) - Measures
O&M costs per total number of active water accounts.
Average of Previous Years = $405
2008 Data:
■ Total O&M costs = $13,226,875
■ # of water accounts = 28,340
■ Ratio = $467 per account
O&M Cost per Account (Water)
O 600
v
v
M
W 500
L.
M
400
Median
c 300 CoB Avg
CoB 2008
200
L
d
Q
N 100
O
V
a 0
oES e~~ Jar e~~
O o o 0 0 0 a s
5 ~~a o~~ goo ~oo~ooho' L,~o, ~ y~~~ ~ \G`Q
o cA o. P~
Attachment A
13b) O&M Cost per Million Gallons Distributed - Measures O&M costs per annual
million gallons distributed.
Average of Previous Years = $1,804
2008 Data:
■ Total O&M costs = $13,226,875
■ Volume distributed = 6,173 million gallons
■ Ratio = $2,143 per MG distributed
O&M Cost per Million Gallons Distributed
L4 3500 -
ca
3000
O
2500
Median
L
2000 C o B Avg
0
1500 CoB 2008
~
L
CL 1000
O
U 500
06 ey` Jar ay` °°°o °°O °°O °°o lea 0IIt ~Nl~
e
4\ dot` h ` G G
Attachment A
13c) O&M Cost of Treatment per Million Gallons Treated - Measures O&M costs
directly attributed to water treatment per annual million gallons treated.
Average of Previous Years = $591
2008 Data:
■ O&M costs (treatment) = $4,122,965
■ Volume treated = 6,173 million gallons
■ Ratio = $668 per MG treated
O&M Cost of Treatment per Million Gallons Treated
a
1600
M
d
L
F- 1400
O
1200
L
Q~ ^
Q- C7 1000 Median
c
800 CoB Avg
L °a 600 CoB 2008
0 400
0 200
U
c 0
O 1 ~ oo~ 000 000 000 aP
5 .a o' h~ ~00 •~00 Leo P~
o cP o. P~
Attachment A
14a) Planned Maintenance Ratio (water, hours) - Measures the percentage of planned
maintenance hours to total maintenance hours for the water utility. Total maintenance is
comprised of both planned and corrective maintenance.
Average of Previous Years = 70.8%
2008 Data:
■ Planned hours = 10,142
■ Corrective hours = 3,562
■ Ratio = 74.0% planned
Planned Maintenance Ratio: Water (Hours)
L
Q
s 90.0
V
80.0
i 70.0
0
Z 60.0
Median
50.0
M CoB Avg
_ 40.0
CL CoB 2008
M 30.0
2
0 20.0
10.0
M
0.0
~t
el °ay` 00~ 0~ 000 000 000 a a~~ a~ m~`y
a
-7 N
00 00 0cP ~ \~Q
Apo, ~o, ~ P
Attachment A
14b) Planned Maintenance Ratio (water, cost) - Measures the percentage of planned
maintenance cost to total maintenance cost for the water utility. Total maintenance is
comprised of both planned and corrective maintenance.
Average of Previous Years = 64.3%
2008 Data:
■ Planned cost = $455,146
■ Corrective cost = $216,674
■ Ratio = 67.7% planned
Planned Maintenance Ratio: Water (Cost)
v 90.0
80.0
p 70.0
U
m 60.0
c 'a Median
m m 50.0
0 ~ 40.0 CoB Avg
o. CoB 2008
30.0
c 20.0
10.0
c
0.0
L
a ~~r may` ay` o~ cA o° o° ° ~a w~` met
Attachment A
15) Sewer Overflow Rate - Reports the number of sanitary sewer overflows (SSO's)
experienced per 100 miles of collection piping. SSO's that originated in a customer's
sewer lateral are not included. These SSO's are excluded to reflect only SSO's for which
the city of Boulder was responsible.
Average of Previous Years = 2.48
2008 Data:
■ # of SSO's = 19
■ Total miles of piping = 349
■ Overflow Rate = 5.44 SSO's / 100 miles
Sewer Overflow Rate
18.00
16.00
14.00
N
12.00
Median
C 10.00
N 8.00 CoB Avg
0 6.00 COB 2008
cn
cn 4.00
2.00
0.00
00 00 00 000 °a °
~
00 00 000 ~ P~Q
Attachment A
16) Collection System Integrity - Measures the total number of collection system
failures divided by the total miles of collection system piping. A "failure" is defined as a
loss of capacity due to flow restriction.
Average of Previous Years = 12.3
2008 Data:
■ # of failures = 53
■ Total miles of piping = 349
■ System Integrity = 15.2 failures / 100 miles
Wastewater Collection System Integrity
60.0
50.0
°0 40.0
Median
30.0 CoB Avg
M CoB 2008
LL 20.0
4W
10.0
N C
0.0
r
4 oJ~ *F eP N o~ o00 000 ~~a a`~ \\a`~
ooh o~, Co ~a5 Qa~
~ooo goo ,gyp P~
Attachment A
17) Wastewater Treatment Effectiveness Rate - Reports the percentage of days in 2005
during which the wastewater facilities were in full compliance with effluent quality
standards.
Average of Previous Years = 99.4%
2008 Data:
■ # of noncompliance days = 5
■ Effectiveness rate = 98.6°/%
Wastewater Treatment Effectiveness Rate
3
100.0 TIA- 1 99.5
E c 99.0
U 98.5
98.0 Median
LL
m
c 97.5 CoB Avg
L d
4m tm 97.0 CoB 2008
96.5
0
0 96.0
95.5
c
P 95.0
L
a- c ~r 5~ 0 0 0
0 0° o. P~
Attachment A
18a) O&M Cost per Account (wastewater) - Measures O&M costs per total number of
active wastewater accounts.
Average of Previous Years = $289
2008 Data:
■ Total O&M costs = $9,733,286
■ # of wastewater accounts = 27,082
■ Ratio = $359 per account
O&M Cost per Account (Wastewater)
O 450
v
m 400
M 350
300
c 250 Median
CoB Avg
200
CoB 2008
Q 150
L
Q 100
50
0
~y~
06
0
e~5~
Ie3
O -300A' X00'
O' Ip
Attachment A
18b) O&M Cost per Million Gallons Processed - Measures O&M costs per annual
million gallons processed.
Average of Previous Years = $1,509
2008 Data:
■ Total O&M costs = $9,733,286
■ Volume processed = 4,839 million gallons
■ Ratio = $2,011 per MG processed
O&M Cost per Million Gallons Processed
O
6000
L
0 5000
N 4000
Median
o00 3000 CoB Avg
CoB 2008
2000
L
Q' 1000
0
U
2 0
06 4- ~r 5~ 5~ O O O O a < <
O ~e of o0 00 00 00 0° aye
~~ar goo goo X00
O~ 00~ CG~~~~' Qa~
o c9 0• P~
Attachment A
18c) O&M Cost of Treatment per Million Gallons Treated - Measures O&M costs
directly attributed to wastewater treatment per annual million gallons treated.
Average of Previous Years = $799
2008 Data:
■ O&M costs (treatment) = $5,357,252
■ Volume treated = 4,839 million gallons
■ Ratio = $1,107 per MG treated
O&M Cost of Treatment per Million Gallons Processed
a~
v 4000
O
G. 3500
U
3000
CL 2500 Median
2000 CoB Avg
0 1500 CoB 2008
L
~ 1000
O
N 500
O
U 0
000 000 Za
06
00 00 0cP ~ \~Q
~00~O~ P
Attachment A
19a) Planned Maintenance Ratio (wastewater, hours) - Measures the percentage of
planned maintenance hours to total maintenance hours for the wastewater utility. Total
maintenance is comprised of both planned and corrective maintenance.
Average of Previous Years = 87.3°/%
2008 Data:
■ Planned hours = 13,081
■ Corrective hours = 848
■ Ratio = 93.9% planned
Planned Maintenance Ratio: Wastewater (Hours)
L
a
100.0
90.0
L 80.0
0 70.0
60.0 Median
c
M 50.0 CoB Avg
n, 40.0 CoB 2008
M 30.0
p 20.0
10.0
M
0.0
as
(P ems`
Co a5 al`
00 00 ocA ~ P~Q
Attachment A
19b) Planned Maintenance Ratio (wastewater, cost) - Measures the percentage of
planned maintenance cost to total maintenance cost for the wastewater utility. Total
maintenance is comprised of both planned and corrective maintenance.
Average of Previous Years = 87.3°/%
2008 Data:
■ Planned cost = $648,691
■ Corrective cost = $43,744
■ Ratio = 93.7% planned
N Planned Maintenance Ratio: Wastewater (Cost)
t
100.0
90.0
p 80.0
V
4) 70.0
0
M 0 60.0 Median
50.0 CoB Avg
.jj o. 40.0 CoB 2008
30.0
w
C 20.0
4)
2 10.0
4) 0.0
U
d
n. ~o a~ ro O o0 00 0 00° ~a ~a
O^ P\
Attachment B
CITY
~ F 75"' Street Wastewater Treatment Plant
4~,•~~ T (TJ.. D{~ 4049 75" Street, Boulder, Colorado 80301
4 BOULDER Telephone (303) 413-7340
PUBLIC WORKS/UTILITIES FAX(303)413-7373
September 8, 2008
Ms Ginny Torrez
Compliance .Assurance and Enforcement Officer
Water Quality Control Division
Colorado Department of Public Health and Environment
WQCD-PE-B2
4300 Cherry Creek Drive South
Denver, Colorado 80222-1530
Dear Ms Torrez:
The purpose of this letter is to provide additional information related to copper permit limit
exceedances at the City of Boulder (City) wastewater treatment plant (WWTP) in March and
April 2008. These exeeedances were previously reported on the Discharge Monitoring Reports
for those respective months. This letter documents return to compliance for copper, expands on
previous findings, and provides information on additional measures that the City has taken to
address the copper issue.
Final effluent potentially dissolved (PD) copper concentrations were above the daily maximum
permit limit of 35.2 ug/L on three occasions in March, as well as one occasion in April.
Potentially dissolved copper exceeded the 30-day average permit level. of 25.6 ug/L during
March only. The table below summarizes WWTP effluent concentrations of PD copper from
January through July 2008:
30-clay Average Daily Maximum
Month PD Cu u L PD Cu u
Jan 08 9.0 10.4
Feb 08 11.3 14*
Mar 08 48.'1* 66.0*
Apr 08 22.1 56.3
May 08 13.4 16,4
Jun 08 --~--11.1 -13.4
Jul 08 13.9 16.1
* permit limit exceedance -
As shown in the above table, a return to compliance for PD copper was experienced for the
months of May, June, and July on both a 30-day average and daily maximum basis. Data for
August 2008 is not yet available. When WWTP staff first learned of the exceedences, several
actions were taken:
• A review of the data was conducted to see of there were any erroneous values, any
-problems with laboratory analysis, or any concerns about sample integrity. No problems
with sample collection, laboratory analysis, or data reporting were found.
• Due to the major construction still occurring at the WWTP during this time, an
investigation into construction activities and new process operation occurred. While no
construction activities were found to be a cause for the elevated copper levels, the new
centrate return system was being placed into service during this time period. One
contributing factor to the copper exceedences may have been the inconsistent operation
of the centrate system, with occasional slugs of centrate and associated solids being
returned to the liquid stream process. Please refer to the DMR cover letters for March
and April 2008 for more detailed information about the centrate system. and associated
construction.
• An evaluation of influent data and industrial pretreatment activity was performed.
Influent PD copper concentrations during the March and April monitoring periods were
not found to be significantly higher than normal WWTP influent concentrations. A
typical average WWTP influent PD copper concentration is approximately 60 ug/L. It is
noted that one major industrial pretreatment discharger was closing down their operation
during the same time period as the exceedences, but there is no evidence of discharges of
elevated copper from this particular industry. No industrial dischargers were found to be
in violation for copper during this time period. The following table summarizes WWTP
influent and effluent concentrations of PD copper for March and April 2008 based on
daily composite samples.
WWTP Influent WWTP Effluent
Date PD Cu (u } PD Cu (ug/L)
3/10/2008 38.2 M 21.2
3/20/2008 55.4 50.0*
3/26/2008 70.4 57.7
3/3 1 /2008 40.7 66.0*
4/2/2008 19.0 16.1
4/10/2008 52.4 56.3*
4/16/2008 38.7 12.6
4/21/2008 13.1 5.8
* permit limit exceedance
When the March 2008 exceedences were observed, WWTP staff investigated the issue by
conducting a copper sampling effort on April 17, and then a more comprehensive sampling effort
including a mass balance study on. May 6. The May mass balance study involved sampling and
analysis of 27 different samples from major liquid processes, solids processes, and in-plant
recycle wastestreams. While the mass balance effort did not reveal any internal sources of
elevated copper, it did demonstrate "expected" copper behavior. Copper was removed through
the liquid stream processes, by clarification as well as bioaccumulation in the activated sludge
solids. Biosolids samples were found to contain concentrated amounts of copper, as expected.
Liquid effluent and biosolids copper concentrations were well within permit levels during the
study.
The City has taken additional measures to address effluent copper exceedances. These measures
are included in this correspondence to remind CDPHE that the City has been treating copper as a
priority and has dedicated significant time and resources towards consistent permit compliance.
In 2005, in preparation for more restrictive acute and chronic copper effluent limits, which were
to become effective January 2006, Boulder initiated a series of evaluations to determine if
additional copper reductions could be accomplished prior to treatment at the 75`x` Street WWTP.
These evaluations were necessary, since based on past WWTP performance it was anticipated
that the WWTP would not be able to consistently meet the new chronic copper effluent limit of
18 ug/L. The following evaluations were initiated in 2005.
Industrial Pretreatment Program Evaluation. The Industrial Pretreatment QPT) Program
regulates permitted industrial users through local pollutant limitations for a variety of
constituents, including copper. An evaluation was completed on the local limits calculations for
copper and the allowable loading at the WWTP headworks. The current local limits for copper
were approved by EPA in 2004 and reflected a reduction in the allowable copper load to the
WWTP. Further investigation into the copper local limits calculations determined that additional
reductions beyond those made in 2004 from regulated industries would be impractical as most
facilities are currently regulated at or near collection system background concentrations in non-
industrial (residential) areas of Boulder.
Treated Water Corrosion Control Evaluation. In 1993 Boulder implemented a
comprehensive drinking water corrosion control program which focuses on compliance with
drinking water regulations, including the Lead and Copper Rule (40 CFR Part 141). The Lead
and Copper Rule sets standards for both at-the-tap lead and copper levels and requirements for
corrosion control. Based on measured copper concentrations in the treated water distribution
system, Boulder is complying with the Lead and Copper Rule through their current corrosion
control program. Based on a review of Boulder corrosion control program, additional
modifications to try and achieve further reductions in copper pipe leaching may not be
achievable without creating problems with,other drinking water and distribution system goals
and compliance with various drinking water regulatory requirements.
Copper-Based Root Control Elimination and Public Awareness Evaluation. Boulder
evaluated other possible sources of copper, focusing specifically on copper-based root control
products. Multiple local businesses were contacted to determine what quantities, if any, of
copper-based root killers were sold on an annual basis. The evaluation indicted that to accurately
quantify copper-based root killer use in Boulder, and the concentration of constituents such as
copper sulfate, is difficult, but, it was determined that some local Boulder businesses stopped
selling copper-based products and now promote alternative root control. products that do not
contain copper.
To address public awareness in Boulder about the impacts of copper-based root killers, Boulder
developed a Public Works Utilities Flyer and sent it out to utility customers. The Utilities Flyer
focused on educating residents and businesses that copper based root control products can cause
problems at the wastewater treatment facility and alternative root control methods are available.
Implementation of a Temporary Modification for the Copper Water Quality Standard on
Boulder Creek. In 2007, the City of Boulder went before the Colorado Water Quality Control
Commission (Commission) in a Hearing to request a Temporary Modification for a chronic
copper water quality standard on Segment 9 of Boulder Creek. The basis for the Temporary
Modification was to allow additional time to evaluate other options for achieving consistent
compliance with WWTP copper effluent limits. The Colorado Water Quality Control Division
(Division) and Region VIII EPA were also part of the 2007 Hearing for the Temporary
Modification. The final ruling supported a Temporary Modification set to expire
December 31, 2009. Conditions and requirements under the Temporary Modification include:
• The Temporary Modification is defined, by the Division, as "existing quality". The
Division stated (as documented in the Divisions December 29, 2007 Responsive
Prehearing Statement) that the narrative "existing quality„ is "....1-neant to capture the
fact the existing instream quality includes the continuation of copper discharges by the
WWTP at the existing levels".
• Boulder will collect Boulder Creek and 75`x' Street WWTP effluent copper data to
develop a translator, consistent with EPA guidance. This recommendation was supported
by EPA in their May 29, 2007 Responsive Prehearing Statement.
• Boulder will be required to provide updates to the Commission at the December 2007 and
2008 Temporary Modification Hearings on the status of the copper translator study.
Based on Boulder Creek copper data collected to date, it appears that a copper translator of
approximately 1.6 could be applied to the current copper table value standard for Segment 9 of
Boulder Creek. Boulder anticipates that an approximate 60 percent increase in the copper
standard will be sufficient to maintain compliance with copper effluent limits based on the
revised standard. Final results from the copper translator study will be presented to the
Commission in June 2009.
As a final note, the City recently hired a new employee with the role of Process Optimization
Specialist. The Process Optimization Specialist is responsible for assisting with studies and
evaluations of new and existing treatment processes, with the goal of optimizing treatment and
helping achieve consistent permit compliance. The Process Optimization Specialist will help
evaluate and identify solutions for effluent copper. If there are any questions regarding our
efforts to investigate the copper issue, please contact me at 303-413-7341.
Sincerely,
Chris Douville
Coordinator of Wastewater Treatment
c: Ned Williams, Director of Public Works for Utilities
Sue Ellen Harrison, Assistant City Attorney
Bret Linenfelser, Water Quality and Environmental Services Coordinator
Sheri Duren, Process Optimization Specialist