ANALYSIS OF WATER DEMAND AND CONSUMPTION BY...

City of Guelph

Analysis of Water Demand and Consumption by Sector

C3 Water Inc., A C3 Group Company Delivering Value Through The Water Cycle:

350 Woolwich St. S. Source to Tap, Tap to Source

Breslau ON N0B 1M0 i

To: Emily Stahl Company: City of Guelph

From: Sam Ziemann Our File: 75-41-151088

Cc: Wayne Galliher, Bill Gauley Date: 6 April 2016

Subject: Analysis of Water Demand and Consumption by Sector The contents of this memorandum are intended only for the recipient. Any other use and/or reproduction without prior consent of C3 Water Inc. is strictly prohibited.

ANALYSIS OF WATER DEMAND

AND CONSUMPTION BY SECTOR

C3 WATER INC.

6 April 2016

VERSION DATE DESCRIPTION OF REVISIONS REVISED BY REVIEWED BY

1 January 27, 2016 Draft Water Demand and Consumption

by Sector

Bill Gauley Sam Ziemann

2 March 11, 2016 Draft Water Demand and Consumption

by Sector

Bill Gauley

Andrea Williams

Sam Ziemann

3 April 6, 2016 Final Water Demand and Consumption

by Sector

Bill Gauley

Andrea Williams

Sam Ziemann

City of Guelph




Breslau ON N0B 1M0 ii

Table of Contents

Introduction ..................................................................................................................................................1

2014 Draft Water Supply Master Plan Projections and Targets ...................................................................3

Historical Water Production and Demand Rates..........................................................................................6

Historical Customer Sector Demand Rates ............................................................................................... 15

Residential Customers ........................................................................................................................... 15

Low Density Residential Sector ............................................................................................................. 17

4.2.1 Spatial Trends in Low Density Residential Sector .......................................................................... 17

4.2.2 Consumption by Vintage of homes (2006 – 2014) ........................................................................ 21

Multi-family Residential Sector ............................................................................................................. 23

Medium Density Residential Sector ...................................................................................................... 24

4.4.1 Spatial Trends in Medium Density Residential .............................................................................. 24


High Density Residential Sector ............................................................................................................. 29

4.5.1 Spatial Trends in High Density Residential .................................................................................... 29


Industrial, Commercial, Institutional Customers ................................................................................... 34

4.6.1 Consumption by Industry .............................................................................................................. 36

4.6.2 Top 100 Consumers ....................................................................................................................... 39

Non-revenue Water ............................................................................................................................... 43

Summary .................................................................................................................................................... 45

References ................................................................................................................................................. 47

City of Guelph




Breslau ON N0B 1M0 1

INTRODUCTION

The City Guelph is a vibrant and growing community. Its current (2015) population of approximately 135,800 is

expected to grow by 37 percent to 186,300 by 2038. Typically, municipal water demands rise in concert with a

growing population, however, Guelph – one of the largest communities in Canada reliant on a groundwater as

a source of municipal water supply – has been proactive in the field of water efficiency for almost 20 years and

thus does not see the same rise in demand with population as other communities.

In 2006, Guelph City Council approved a Water Supply Master Plan (Master Plan). This Master Plan identified a

number of preferred options including: reclaiming water supply capacity and optimizing the use of the City’s

water supply infrastructure; employing enhanced water conservation and efficiency strategies; mitigating

distribution-based water loss; and conducting education/policy/rate-based reviews. The 2006 Water Supply

Master Plan, recognized that sustainable growth in the City was contingent upon the success of aggressive

water conservation and efficiency programs, especially in the short term. The 2006 Water Supply Master Plan

projected that the baseline (i.e., without water efficiency) average annual day production rate would increase

from 53,000 cubic metres per day in 2006 to about 73,700 cubic metres per day in 2025 unless the City

successfully implemented a number of water efficiency measures. The 2007 Water Supply Master Plan also

identified the following time-based average annual day water production reduction targets:

• Reduction of 10 percent (5,300 cubic metres per day) in average day water use by 2010;

• Reduction of 15 percent (7,950 cubic metres per day) in average day water use by 2017; and

• Reduction of 20 percent (10,600 cubic metres per day) in average day water use by 2025.

Figure 1 illustrates the 2007 Water Supply Master Plan projected baseline production rates (which includes no

water conservation or efficiency) and target production rates (includes water conservation and efficiency) from

2006 to 2025, as well as the actual water production rates in the City between 2006 and 2015. As seen in

Figure 1, actual production rates in Guelph were substantially lower than the target rates identified in the 2006

Water Supply Master Plan. The lower than expected production rates were the result of three main factors: the

effectiveness of the City’s water efficiency measures and programs, the recent natural shift in the plumbing

fixture and appliance marketplace towards the development and sale of more efficient models, and a growing

public awareness of the need to use our natural resources efficiently.

City of Guelph





Figure 1: 2006 Water Supply Master Plan Projections and Targets and Actual Production (2006 – 2014)

City of Guelph





2014 DRAFT WATER SUPPLY MASTER PLAN PROJECTIONS AND TARGETS

Baseline water production projections and demand reduction targets were revised in the 2014 Guelph City

Council approved Draft Water Supply Master Plan to reflect the lower production rates being experienced by

the City. The 2014 Water Supply Master Plan was initiated to build upon previous work completed and take

into account more recent studies and work activities over the past six years. The 2014 Water Supply Master

Plan projected that baseline production rates (i.e., without water efficiency or conservation) would increase

from 48,253 cubic metres per day in 2013 to 69,872 cubic metres per day in 2038. The 2014 Water Supply

Master Plan also set a target of reducing this projected 2038 rate by 9,147 cubic metres per day to only 60,725

cubic metres per day – a reduction of about 13 percent in average day water use.

The 2014 Water Supply Master Plan projections and targets were developed based on expected population

growth in the City, residential water demands, Industrial/Commercial/Institutional water demands (based on

equivalent population values), and non-revenue water volumes. Figure 2 and Table 1 present the 2014 Water

Supply Master Plan baseline and target values based on achieving a 13 percent reduction in residential,

employment, and non-revenue water demands between 2013 and 2038. Note that, because of the growing

population, the overall average daily demand for the City, as well as demands for all sub-sectors, will continue

to increase under both the baseline (no efficiency and conservation) and target savings scenarios. When

demands are presented on a per capita basis it can be seen that the 2014 Water Supply Master Plan is

targeting declining demands overall and for all sub-sectors (Figure 3 and Table 2). Note that for illustrative

purposes a 13 percent reduction has been shown for all sub-sectors; in reality, more savings may be achieved

in some sub-sectors and less savings in others. The key target is an overall reduction in production rates of

9,147 cubic metres per day or 13 percent in average day water use by 2038.

City of Guelph





Figure 2: 2014 Draft Water Supply Master Plan Projections and Targets

Table 1: 2014 Draft Water Supply Master Plan Production Projections and Targets, Cubic Metres per Day

Year Residential Employment Non-revenue Water Total

Baseline Target Baseline Target Baseline Target Baseline Target

2013 23,536 23,536 19,059 19,059 5,658 5,658 48,253 48,253

2018 25,843 24,842 21,100 20,283 6,175 5,936 53,118 51,061

2023 28,150 26,152 23,140 21,497 6,691 6,216 57,981 53,865

2028 30,293 27,246 25,803 23,207 7,208 6,483 63,304 56,936

2033 32,144 28,272 27,690 24,354 7,628 6,709 67,462 59,335

2038 33,555 29,162 28,413 24,693 7,903 6,868 69,871 60,724

City of Guelph





Figure 3: 2014 Water Supply Master Plan Per Capita Projections and Targets

Table 2: 2014 Draft Water Supply Master Plan Water Production Projections and Targets, Litres per Capita

Year Residential Employment Non-revenue Water Total

Baseline Target Baseline Target Baseline Target Baseline Target

2013 180 180 286 286 43 43 369 369

2018 180 173 286 275 43 41 370 356

2023 180 167 286 265 43 40 371 345

2028 180 162 286 257 43 39 376 339

2033 180 158 286 251 43 38 378 332

2038 180 157 286 248 42 37 375 326

City of Guelph





HISTORICAL WATER PRODUCTION AND DEMAND RATES

The City’s average annual day water production targets are sought from both customer demands and water

that is produced but not utilized by customers (e.g., water lost through leakage). Since 2006, customer water

demands (employment and residential) have accounted for about 85 percent of total water production

volumes. Therefore, only about 15 percent of all water produced by the City is not used by its customers (Table

3). Water that is produced but not billed to customers is referred to as non-revenue water. Non-revenue water

includes physical losses such as water used for firefighting, mains flushing, system leakage, un-metered

municipal uses, such as commission of new infrastructure, as well as, apparent losses resulting from metering

or accounting inaccuracies.

Table 3: Actual Production versus Actual Demand, 2006 – 2014

Year Actual Production,

Cubic Metres per Day

Actual Demand,


Percent Demands,

Percent

2006 51,387 43,626 85

2007 51,005 43,188 85

2008 48,492 40,499 84

2009 46,607 39,120 84

2010 44,442 38,714 87

2011 45,578 39,460 87

2012 45,244 38,179 84

2013 44,379 38,326 86

2014 45,463 37,478 83

If we breakdown the production and consumption values, between 2006 and 2014 approximately 51 percent

of the water produced was used by residential customers, 34 percent by industrial, commercial and

institutional customers, and about 15 percent was attributed to non-revenue water (Figure 4 and Table 4).

City of Guelph





Figure 4: Historical Water Production, 2006 – 2014

Table 4: Historical Water Production, 2006 to 2014

Year Production, Cubic

Metres per Day

Residential Demand,


Industrial/Commercial

/Institutional Demand,


Non-revenue Water,


2006 51,387 25,752 17,873 7,762

2007 51,005 26,053 17,134 7,818

2008 48,492 25,013 15,486 7,993

2009 46,607 23,138 15,982 7,487

2010 44,442 22,635 16,079 5,728

2011 45,578 22,243 17,217 6,118

2012 45,244 23,233 14,946 7,065

2013 44,379 22,714 15,612 6,053

2014 45,463 22,373 15,374 7,716

Water production rates in Guelph have declined since 2006 despite the growing population. Between 2006 and

2014 the City’s production rates declined by approximately 852 cubic metres per day per year (based on linear

trend) and water demand (consumption) rates have declined by only slightly less at 725 cubic metres per day

per year (Figure 5 and Table 5). Note that when linear trend lines are included in Figures in this report, the

equation and R2 value for the trend line is displayed. The R2 value is a statistical measure of how close the data

are to the fitted regression line - the higher the R2 value the better the fit with a value of 1.0 indicating a

perfect fit.

City of Guelph





Figure 5: Historical Water Production and Water Demand Rates

City of Guelph





Table 5: Historical Water Production Values, Cubic Metres per Day

Year Population Average Annual Day

Demand Production

Average Annual Day

Demand Consumption Peak Day

2006 115,040 51,387 43,626 61,456

2007 116,766 51,005 43,188 63,652

2008 118,491 48,492 40,499 58,440

2009 120,491 46,607 39,120 55,337

2010 121,093 44,442 38,714 53,691

2011 123,000 45,578 39,460 64,416

2012 124,250 45,244 38,179 58,764

2013 126,250 44,379 38,326 52,539

2014 128,726 45,463 37,748 52,614

While peak day demands also declined by an average of 983 cubic metres per day per year during this time,

peak demands are highly variable from year to year based on local weather conditions – making them difficult

to accurately predict in the future based on past results. Peak day demands generally occur after an extended

period of hot and dry weather and are largely due to an increase in irrigation demands. While an unusually hot

or dry summer season would be expected to produce a high peak day demand, a summer with typical weather

conditions (or even an overall cool and wet summer) can also produce high peak day demands if there is a two-

or three-week period of drought over the entire May to September irrigation season. For example, Table 6

presents the peak day water demand for the years 2006 to 2014, along with the mean May to September

temperature and total May to September precipitation in millimetres1. Note that there is little difference in

mean summer temperatures for these years (from a low of 15.3 degrees Celsius in 2009 to a high of 17.3

degrees Celsius in 2012) and the variation in mean temperature values does not appear to have a strong

correlation to peak day demands.

Table 6: Historical Peak Day Demand, Mean Temperature and Total Precipitation from May to September

Year Peak Day Demand,

Million Litres per Day

Mean Temperature,

degrees Celsius

Total Precipitation,

Millimetres

2006 61.5 16.9 473

2007 63.7 16.9 297

2008 58.4 15.8 539

2009 55.3 15.3 374

2010 53.7 16.9 517

2011 64.4 16.9 467

2012 58.8 17.3 292

2013 52.5 16.4 568

2014 52.6 15.5 339

1 Weather data from Region of Waterloo International Airport.

City of Guelph





For example, as presented in Figure 6, one of the lowest peak day demands during this period occurred in 2010

at 53.7 million litres per day with a mean summer temperature of 16.9 degrees Celsius. While the highest peak

day demand during this period occurred in 2011 at 64.4 million litres per day, the mean summer temperature

in this year was also 16.9 degrees Celsius. In 2012 the peak day demand fell to 58.8 million litres per day but

the mean summer temperature actually increased to 17.3 degree Celsius.

Figure 6: Historical Peak Day Demand versus Mean Summer Temperature

While there is a significant variation in total summer season precipitation between 2006 and 2014 (from a low

of 292 millimetres in 2012 to a high of 568 millimetres in 2013), the correlation between total summer

precipitation and peak day demands is not immediately apparent. For example, as presented in Figure 7, the

peak day demand in both 2007 and 2011 was about 64 million litres per day, but 2007 only received 297

millimetres of rain between May and September while 2011 received 467 millimetres. Similarly, 2013 and 2014

had almost identical peak day demands but 2013 received 568 millimetres of rain while 2014 only received 339

millimetres.

City of Guelph





Figure 7: Historical Peak Day Demand versus Total Summer Precipitation

The real impact of improved water and conservation efficiency in the City is best illustrated by considering per

capita demands. As presented in Figure 8 and Table 7, per capita rates declined for all aspects of water

production between 2006 and 2014 – average annual day, average winter day, average summer day, and peak

day. Average annual day production rates declined by an average of 12.3 litres per capita per day per year

(based on linear trend), winter day rates (reflecting indoor use) declined by 12.0 litres per capita per day per

year, summer day rates declined by 12.6 litres per capita per day per year, and peak day rates declined by 14.4

litres per capita per day per year.

City of Guelph





Figure 8: Historical per Capita Water Production Rates

Table 7: Historical Water Production Rates, Litres per Capita per Day

Year Winter Day Summer Day Average Annual Day Peak Day

2006 435 461 447 534

2007 423 455 437 545

2008 403 417 409 493

2009 385 389 387 459

2010 359 378 367 443

2011 355 393 371 524

2012 352 381 364 473

2013 346 359 352 416

2014 347 361 353 409

City of Guelph





While average annual day water production rates declined by an average of 12.3 litres per capita per day per

year (based on linear trend) between 2006 and 2014, average annual day demand rates declined by only 10.4

litres per capita per day during the same period (Figure 9) with the highest rate of demand decline occurring

between 2006 and 2009. When only the years 2009 to 2014 are considered the decline in per capita production

rates was 6.3 litres per capita per year and the decline in per capita demand rates was very similar at 6.6 litres

per capita per year (Figure 10), i.e., the rate of annual decline of production and demand is lower now than it

was a decade ago. The following sections outline water demands in the various customer sectors.

Figure 9: Guelph Historical Values; Population, Gross per Capita Production, and Gross per

Capita Demand (2006 – 2014)

City of Guelph





Figure 10: Guelph Historical Values; Population, Gross per Capita Production, and Gross per

Capita Demand (2009 – 2014)

City of Guelph





HISTORICAL CUSTOMER SECTOR DEMAND RATES

As presented in Section 3, overall water production, demand, and per capita demand values have declined in

the City since 2006. By evaluating the demands for each customer sector individually it was possible to identify

the demand trend for low density residential customers, medium and high density residential customers, and

industrial, commercial, and institutional customers.

Residential Customers

Residential customer billing data was available for the years 2006 through 2014 (inclusive). Figure 11 and Table

8 present historical average annual day residential water demands in the City between 2006 and 2014. As

presented, water demands in the low-density residential customer sector declined by about 6.07 litres per

capita per day per year during this period (based on the linear trend), while demands in the combined medium-

and high-density residential customer sector declined by 7.37 litres per capita per day per year. The accuracy of

the linear trend is very high for both residential customer sectors (R2 values of 0.96 and 0.97).

Figure 11: Historical Residential Water Demands (2006 - 2014)

City of Guelph





Table 8: Historical Residential Water Demands, Litres per Capita per Day

Year Combined Low Density Medium and High Density

2006 224 211 249

2007 223 211 245

2008 211 197 238

2009 204 189 231

2010 198 184 226

2011 192 178 219

2012 187 178 203

2013 180 167 205

2014 174 165 189

The reduction in Guelph’s residential water demands has been the result of the effectiveness of the City’s

water efficiency measures (direct savings) combined with changes to the Ontario Building Code and the impact

of the recent marketplace shift towards more efficient plumbing fixtures and appliances (natural savings), and

a growing public awareness of the need to use our natural resources wisely (indirect savings).

Since the introduction of the United States Environmental Protection Agency’s WaterSense® program in 2006,

the focus of most plumbing fixture manufacturers has been on developing water-efficient products. As such,

most toilets, showerheads, and faucets available in the marketplace are efficient models. The United States

Environmental Protection Agency’s ENERGY STAR program has had a similar impact regarding the efficiency of

clothes washers and dishwashers available in the marketplace. Largely because of the improved efficiency of

plumbing fixtures and appliances available in the marketplace there has been a decline in per capita residential

water demands across North America. In fact it is estimated that the current rate of natural indoor residential

savings is about 2.7 litres per capita per day per year.2

Of course, such a significant rate of decline cannot go on indefinitely3. The current rate of demand decline is

expected to slow down as average residential demands move closer to approximately 150 litres per capita per

day and there are fewer inefficient customers available in the City to convert to efficient customers

(WaterSense, 2008). With a current combined residential demand of only 174 litres per capita per day, the City

anticipates it will reach its 2038 single-family water demand target ahead of schedule.

2 Based on detailed in-home monitoring completed in 737 representative homes in nine different cities in the USA and Canada as part of

the 1999 Residential End Use Study (AWWRF) and the 2014 Residential End Use Study Update (National Research Centre Inc.) over the

15-year period between 1999 and 2014 average per capita indoor demands have declined by from 262.3 litres per capita per day to

221.8 litres per capita per day, a reduction of 40.5 litres per capita per day in 15 years for an average of 2.7 litres per capita per day per

year. This reduction was found to be statistically significant at the 95 percent confidence level.

3 With the growing impact of WaterSense® and ENERGY STAR on the efficiency of fixtures and appliances in the marketplace, achieving

an average City-wide indoor residential water demand of about 150 litres per capita per day should be achievable.

City of Guelph





Low Density Residential Sector

As stated previously, Guelph’s single-family residential sector had a daily demand of 165 litres per capita in

2014. To put these values into context, the following table outlines per capita residential demands for

comparable municipalities and also leading countries in water efficiency.

Table 9: Single-family Per Capita Demands

City/Country Litres per Capita per Day

Region of Waterloo (2014)4 184

Region of Peel (2015)5 188

Toronto (2014)6 200

Calgary (2015)7 219

Region of York (2014)8 200

Markham (2014)9 189

United Kingdom (2014)9 150

Austria (2014)9 135

Germany (2014)9 122

Guelph (2014)9 165

4.2.1 Spatial Trends in Low Density Residential Sector

Figure 12 illustrates water demands for Guelph’s low density single-family residential sector in 2013 divided

into the following water demand ranges:

• Top 5 percent: greater than 358 cubic metres per year,

• Top 5 to 20 percent: 248 to 358 cubic metres per year,

• Bottom 80 percent: 0 to 248 cubic metres per year.

In 2013, 13.5 percent of the total low density residential water demand was consumed by the top 5 percent of

single-family homes, 23.5 percent of demand was consumed by the top 5 to 20 percent, and 63 percent of

demand was consumed by the bottom 80 percent of accounts. As illustrated in Figure 13, “hot spots” for high

annual use are shown to occur in the centre-north, centre-south, west and southeast side suburban areas of

the City. These observations agree with those outlined in previous water demand reports (Fortin, 2013), which

noted high annual use in the centre-west and southwest areas of the City.

4 Value extrapolated from single-family demands identified in May 13 Water Efficiency Master Plan Update Technical

Memo #1 (Figure 22). 5 Value proved by Peel Region. 6 Value provided by City of Toronto Staff 7 Value from 2016 Water Efficiency Plan Update 8 Value from 2016 Long Term Water Conservation and Efficiency Strategy 9 Markham website (www.markham.ca/wps/portal/Markham/Residents/Water/WaterConserv/Conservation/)

City of Guelph





Several attributes were reviewed to identify any key relationships between the different high water use “hot

spots”. Table 10 lists the attributes and associated averages for the 3 ranges in water use. The average age of

homes in the two top ranges are the same at 34 years, but the average home size in the top 5 percent

customers is 124 percent larger than that of the 5 to 20 percent customers. The top 5 percent customers also

have an average of 122 percent more bathrooms than the top 5 to 20 percent customers. That said, even these

differences don’t fully explain why the top 5 percent customers tend to use 175 percent more water than the

top 5 to 20 percent customers. The bottom 80 percent of customers tend to live in older, smaller homes with

fewer bathrooms, however, people do not tend to base how often they use the washroom, wash their clothes,

or shower based on the size of their home or the number of bathrooms they have. The average summer and

winter demands are similar for all three ranges indicating that the difference in demands between the ranges is

not due to differential summer irrigation use. While the magnitude of the difference in water demands in the

three ranges cannot be fully explained by the age or size of home, or even number of bathrooms, it may be

that larger homes fitted with more bathrooms have higher occupancy rates, i.e., the difference in the per

capita demand for these three ranges is not as pronounced as the difference in household demand.

Table 10: Low Density Residential Statistics, 2013 Averages

Monthly Water Demand,

Cubic Metres per Month

Selected Attributes

Ranges Average

Annual Summer Winter

Age of Home,

Years

Structural Area,

Square Feet

Number of

Bathrooms

Top 5 percent 42 42 41 34 2,684 2.2

Top 5 to 20 percent 24 23 25 34 2,162 1.8

Bottom 80 percent 12 12 12 43 1,827 1.6

City of Guelph





Figure 12: Low Density Residential Water Consumption by Parcel, All Ranges (2013)

City of Guelph





Figure 13: Low Density Residential Water Consumption by Parcel, Top 20 percent (2013)

City of Guelph





4.2.2 Consumption by Vintage of homes (2006 – 2014)

In 1996, the Ontario Building Code mandated the use of 6-litre toilets in new construction, therefore an

analysis was conducted to compare demands for homes built pre- and post-1996. Data was analyzed yearly

with the top and bottom 1 percent removed to reduce/eliminate errors and outliers. Average monthly demand

rates from 2006 to 2014 were reviewed. Average annual monthly demands, average summer demands, and

average winter demands were compared (Figures 14, 15 and 16). The results show that homes built pre-1996

consistently have lower average annual and winter day demands compared to post-1996 homes. The reason

for this result is not known but could be a result of lower per capita occupancy rates in the older homes or

perhaps many of the older homes have already replaced their existing plumbing fixtures and appliances with

water efficient models. The difference in average summer day demands is mixed with older homes having

higher demands between 2006 to 2009 and newer homes having higher demands between 2011 and 2014.,

The reason for this result may be related to the increasing differential between winter (indoor) demands

between pre- and post-1996 homes (i.e., summer demands reflect both indoor and outdoor water use).

Figure 14: Low Density Residential Average Annual Demand (2006 – 2014), Homes

Constructed Pre- and Post-1996, Cubic Metres per Month

City of Guelph





Figure 15: Low Density Residential Average Summer Demand (2006 – 2014), Homes


Figures 16: Low Density Residential Average Winter Demand (2006 – 2014), Homes


City of Guelph





Multi-family Residential Sector

Multi-family residences in Guelph are either directly metered (each unit has its own water meter) or bulk

metered where a single meter services more than one unit or an entire building. Water demand data from

2006 to 2014 were analysed.

Figure 17 depicts the monthly average consumption of bulk and directly metered accounts by average annual,

summer and winter months on a per unit basis. As presented, directly metered accounts have lower average

annual demands than bulk metered accounts. The total average annual monthly consumption between 2006

and 2014 is 13.5 and 10.8 cubic metres for bulk and directly metered accounts respectively. This differential

may be the result of higher occupancy rates, less efficient fixtures, or less efficient occupants (because they

don’t pay water bill) in bulk metered buildings. Higher winter versus summer water demands in directly

metered units may be the result of higher occupancy rates during the winter months due to student housing.

Figure 17: Bulk versus Directly Metered Multi-family Residential Customers (2006 - 2014)

City of Guelph





Medium Density Residential Sector

4.4.1 Spatial Trends in Medium Density Residential

Figure 18 shows water demand for Guelph’s medium density multi-family residential sector in 2013 divided

into the following water demand ranges:

• Top 5 percent: greater than 412 cubic metres per year,

• Top 5 to 20 percent: 245 to 412 cubic metres per year,

• Bottom 80 percent: 0 to 245 cubic metres per year.

“Hot spots” are shown to occur in the suburban areas (Figure 19), especially in the Western and Southern areas

of the City. In 2013, 25 percent of the total medium density residential water demand was consumed by the

top 5 percent of accounts. The top 5 to 20 percent of medium density residential accounts consumed 22

percent of the water demand, while the lower 80 percent of accounts consumed 53 percent of the demand.

Table 11 lists the attributes and associated averages for the ranges. The results show that older homes use

more water, that larger homes use more water, and that homes with more bathrooms use more water. While

it is expected that larger homes with more bathrooms are likely to have higher occupancy rates, the top 5

percent of homes use an average of eight times more water than the bottom 80 percent of homes. It is likely

that this significant differential is the result of a combination of higher occupancy rates in the top 5 percent of

homes combined with a lower level of fixture and appliance efficiency.

Table 11: Medium Density Residential Statistics, 2013 Averages



Selected Attributes

Ranges Average


Age of Home,

Years

Structural Area,

Square Feet

Number of

Bathrooms

Top 5 percent 89 92 83 71 3,362 4.0

Top 5 to 20 percent 25 25 26 50 1,953 2.0

Bottom 80 percent 11 11 12 38 1,617 1.5

City of Guelph





Figure 18: Medium Density Residential Water Consumption by Parcel, All Ranges (2013)

City of Guelph





Figure 19: Medium Density Residential Water Consumption by Parcel, Top 20 Percent (2013)

City of Guelph






Medium density data was analyzed yearly with the top and bottom 1 percent removed to reduce/eliminate

errors and outliers. Average annual, summer and winter monthly water demands were recorded for each year

(2006 to 2014). Figures 20, 21 and 22 show that medium density residential home constructed post-1996 have

significantly lower monthly average demands in all three metrics compared to pre-1996 homes.

Figure 20: Medium Density Residential Average Annual Demand (2006 – 2014), Homes


Figure 21: Medium Density Residential Average Summer Demand (2006 – 2014), Homes


City of Guelph





Figure 22: Medium Density Residential Average Winter Demand (2006 – 2014), Homes


City of Guelph





High Density Residential Sector

4.5.1 Spatial Trends in High Density Residential

The following graphic (Figure 23) illustrates geospatial trends in water demand for the high density residential

sector. The following water demand ranges were used to determine geospatial trends for high density

residences:

• Top 5 percent: greater than 19,827 cubic metres per year,

• Top 5 to 20 percent: 9,632 to 19,827 cubic metres per year,

• Bottom 80 percent: 0 to 9,632 cubic metres per year.

“Hot spots” are evident in the southern and eastern areas of the City (Figure 24). In 2013, the top 5 percent of

high density accounts used 23 percent of the water demand. The top 5 to 20 percent of accounts used 37 of

the water, and the lower 80 percent of accounts used only 40 percent of the demand.

Table 12 lists the attributes and associated monthly average water demands for the 3 metrics. As expected, as

the size of the building increases and the number of washrooms increases, the overall water demand increases

(larger buildings are likely to have more units). The difference in water demand per square foot of area for

these three ranges is not as pronounced with the average annual water use for the top 5 percent customers

equal to 0.16 cubic metres per square foot, for customers in the 5 to 20 percent bracket the average demand is

0.13 cubic metres per square foot, and for the bottom 80 percent the average demand is 0.12 cubic metres per

square foot. High water users also tend to use more water per bathroom than low water users, possibly

because of higher occupancy rates or less efficient fixtures. The age of the building does not seem to be a

critical factor.

Table 12: High Density Residential Statistics, 2013 Averages



Selected Attributes

Ranges Average


Age of Home,

Years

Structural Area,

Square Feet

Number of

Bathrooms

Top 5 percent 2,152 1,794 2,407 34 165,257 121.5

Top 5 to 20 percent 1,124 1,062 1,168 35 97,570 82.2

Bottom 80 percent 233 223 240 57 22,522 18.8

City of Guelph





Figure 23: High Density Residential Water Consumption by Parcel, All Ranges (2013)

City of Guelph





Figure 24: High Density Residential Water Consumption by Parcel, Top 20 Percent (2013)

City of Guelph






High density data was analyzed yearly with the top and bottom 1 percent removed to reduce/eliminate errors

and outliers. Average annual monthly demands, average summer monthly demands, and average winter

monthly demands were analyzed for the period 2006 to 2014. High density pre-1996 residential buildings have

significantly lower demands in all three metrics compared to post-1996 buildings (Figures 25, 26 and 27), likely

indicating that they are smaller buildings with fewer units.

Figure 25: High Density Residential Average Annual Demand (2006 – 2014), Buildings


Figure 26: High Density Residential Average Summer Demand (2006 – 2014), Buildings


City of Guelph





Figure 27: High Density Residential Average Winter Demand (2006 – 2014), Buildings


City of Guelph





Industrial, Commercial, Institutional Customers

Industrial, commercial and institutional customer billing data was available for the years 2006 through 2014

(inclusive). Figure 28 illustrates historical average annual day industrial, commercial and institutional water

demands in the City in this time period (note that because the Municipal Property Assessment Corporation

codes were changed in 2012, miscellaneous customers with property codes of ‘000s’, ‘100s’, and ‘200s’ are

included as industrial/commercial/institutional customers, specifically as institutional customers when the

three components are broken out) (table 13).

Figure 28: Historical Industrial, Commercial and Institutional Customer Sector Demands

City of Guelph





Table 13: Historical Industrial/Commercial/Institutional Average Annual Demands, Cubic Metres per Day

Year Industrial Commercial Institutional & Other

2006 10,223 3,570 5,414

2007 9,955 3,540 4,796

2008 8,375 3,526 4,682

2009 8,023 3,320 4,800

2010 8,533 3,374 4,864

2011 9,010 3,312 4,421

2012 9,261 2,956 4,135

2013 9,633 3,114 4,067

2014 9,944 3,209 3,921

Between 2006 and 2014 the overall average annual day demand of the City’s industrial/commercial/

institutional customer sector declined by an average of 214 cubic metres per day while the average per capita

demand (based on the city population) declined by an average of 3.7 litres per capita per day per year (Figure

29).

The 2038 target for industrial/commercial/institutional customers identified in the 2014 Water Supply Master

Plan (based on achieving a 13 percent reduction) is approximately 133 litres per capita per day (based on city

population) – exactly what the demand rate was in 2014 (Figure 29). As such, the City is well ahead of schedule

to reach its 2038 industrial/commercial/institutional target.

City of Guelph





Figure 29: Historical Industrial, Commercial and Institutional Water Demands (2006 – 2014)

4.6.1 Consumption by Industry

All accounts for industrial, commercial and institutional customers were grouped by their North American

Industry Classification System codes and were analysed based on their average annual, summer and winter

monthly consumption. Figure 30 highlights the findings per sector with the number of accounts per sector

found above each column.

City of Guelph





Figure 30: Average Consumption by Industry (2006 – 2014), Cubic Metres per Month

The following table gives the data points for the graph as well as the demand per account for each industry

(Table 14). From the table, the Food and Beverage industry has the highest water demand per account per

month, followed by Nursing Homes and Wholesalers.

City of Guelph





Table 14: Monthly Average Consumption by Nature of Industry (2006 – 2014), Cubic Metres per Month

Industry Average


Number of

Accounts

Demand per

Account

Wholesalers 82,718 80,010 84,806 68 1,216

Food and Beverage 57,656 62,985 53,857 14 4,118

Manufacturing 39,803 41,967 38,386 109 365

Services 35,307 38,788 33,000 226 156

Restaurants/Catering 27,631 29,358 26,485 74 373

Retailers 19,413 21,043 18,510 117 166

Health Care 17,216 19,167 15,932 60 287

Nursing Home 13,196 13,556 12,986 8 1,650

Schools and Universities 7,368 7,236 7,588 56 132

Hotels and Motels 6,321 7,326 5,741 10 632

Organizations/Associations 5,957 6,089 5,881 47 127

Car Washes 5,159 4,480 5,644 9 573

Construction 4,000 4,529 4,024 39 103

Automotive 4,126 4,579 3,849 82 50

Barber Shops/Beauty Salons 1,617 1,699 1,569 19 85

Laundromats 1,092 1,083 1,099 5 218

Transport 563 734 447 15 38

Natural Resources 158 335 43 2 79

City of Guelph





4.6.2 Top 100 Consumers

The top 100 industrial, commercial, institutional accounts were grouped by industry and the water demand per

industry from 2006 to 2014. Because there is such a range in water demand, the yearly consumption per

industry is shown in two separate graphs for clarity.

Figures 31 and 32 present the average annual monthly water demand per year for the top consumers. Figures

33 and 34 illustrates the monthly summer averages, while figures 35 and 36 show the winter monthly averages

per year. To better recognize the trend for each industry for each monthly average examined, the following

table (Table 15) was prepared to summarize the percentage increase or decrease in average annual, summer

and winter monthly consumption from 2006 to 2014. The industries with reduced water consumption have

been highlighted and could be a result of water efficiency technology implementation, recessionary effects on

the industry, or closure of some businesses during the timeframe examined. Many of the areas that had an

increase in water demand can be related to Guelph’s 15 percent growth in population since 2006. The

automotive and construction industries have increased at a greater rate and could be an area for the Water

Smart Business Program (formally Industrial/Commercial/Institutional Capacity Buyback Program) to focus its

marketing.

Table 15: Average Annual Percentage Increase/Decrease in Water Demand for Top 100 water users from

2006 - 2014

Industry Average Annual,

Percent

Summer,

Percent

Winter,

Percent

Food and Beverage 15 7 25

Manufacturing 16 22 13

Retailers -12 -8 9

Services 34 49 26

Schools and Universities -45 -35 -49

Health Care -16 4 -30

Hotels and Motels -40 -45 -36

Restaurants -7 -11 -5

Construction 220 754 134

Wholesalers -6 4 -13

Automotive 274 325 240

Nursing Home 51 44 56

Car Washes 19 -40 65

Organizations/Associations 5 -29 -16

City of Guelph





Figure 31: High Range of Top 100 Water Users for the Industrial/Commercial/Institutional Consumers

Average Annual Water Demand, Cubic Metres per Month

Figure 32: Low Range of Top 100 Water Users for Industrial/Commercial/Institutional Consumers

Average Annual Water Demand, Cubic Metres per Month

City of Guelph





Figure 33: High Range of Top 100 Water Users for Industrial/Commercial/Institutional Consumers

Summer Water Demand, Cubic Metres per Month


Summer Water Demand, Cubic Metres per Month

City of Guelph





Figure 35: High Range of Top 100 Water Users for Industrial/Commercial/Institutional Consumers

Winter Water Demand, Cubic Metres per Month


Winter Water Demand, Cubic Metres per Month

City of Guelph





Non-revenue Water

Non-revenue water is the term used for water that is produced by the City but not sold to customers. Non-

revenue water includes physical losses such as water used for firefighting, mains flushing, system leakage, un-

metered municipal uses, etcetera, as well as apparent losses resulting from metering or accounting

inaccuracies. If the City spends too little to reduce system leakage, the volume and value of water lost each

year will increase; if the City spends too much, the cost of the program will outweigh the savings. Between

these two extremes is an economic level of leakage where program costs and program savings are optimized.

The City’s goal is to reduce and maintain leakage levels at the economic level of leakage for their system10.

The City of Guelph has adopted the International Water Association/American Water and Wastewater

Association Water Audit Method – broadly accepted as the industry Best Practice of water loss accounting - to

manage the level of non-revenue water. The Water Audit Method allows water utilities to assess non-revenue

water levels in their system compared to established benchmarks.

One of the most important elements of the Water Audit Method is the calculation of the system’s

Infrastructure Leakage Index – a ratio of the Current Annual Real Losses in the system to the Unavoidable

Annual Real Losses. A system with an Infrastructure Leakage Index value of 1.0 would have no unavoidable

leakage; a system with an Infrastructure Leakage Index value of 2.0 would theoretically be able to reduce their

leakage level by half.

Guelph’s current (2014) Infrastructure Leakage Index value is 1.59, much lower than the 3.01 value calculated

in 2006. A declining Infrastructure Leakage Index value indicates that the City is reducing the level of avoidable

leakage in their system. Table 16 presents historical Infrastructure Leakage Index values in Guelph between

2006 and 2014. Note that because as existing leaks are discovered and repaired, new leaks are forming,

Infrastructure Leakage Index values will fluctuate from year to year. Table 17 presents the banding/rating

system introduced in 2005 by the World Bank Institute into their non-revenue water training manuals to help

assess system performance. While Guelph would have been classed in Band B from 2006 to 2011 with

Infrastructure Leakage Index values between 2 and 4, since 2012 the City has moved up to Band A with

Infrastructure Leakage Index values of less than 2.0.

Table 16: Infrastructure Leakage Index Values

Criteria 2006 2007 2008 2009 2010 2011 2012 2013 2014

Infrastructure Leakage

Index Value 3.01 2.94 3.3 3.37 3.42 2.68 1.95 1.65 1.59

10 It is not possible to eliminate all leakage in a water supply system. The Economic Level of Leakage is the term used for the level of

leakage below which it costs the municipality more to eliminate than it would recover in cost savings.

City of Guelph





Table 17: World Bank Institute Target Matrix for Infrastructure Leakage Index

Infrastructure Leakage

Index Range

Band General Description of Real Loss Management Performance Categories

for Developed and Developing Countries

1-2 A Further loss reduction may be uneconomic unless there are shortages;

careful analysis needed to identify cost effective improvement.

2-4 B Potential for marked improvements; consider pressure management,

better active leakage control practices, and better network management.

4-8 C Poor leakage record, tolerable only if water is plentiful and cheap; even

then, analyse level and nature of leakage and intensify leakage reduction

efforts.

>8 D Very inefficient use of resources; leakage reduction programs imperative

and high priority.

While the current (2014) estimated non-revenue water rate of 6,197 cubic metres per day is slightly below the

2014 Water Supply Master Plan 2038 target of 6,868 cubic metres per day, average daily production values are

expected to increase by about 35 percent from 2014 to 2038 and, as such, the volume of non-revenue water

expressed as a percentage of production will need to decline from about 14 percent in 2014 to only 11 percent

in 2038.

City of Guelph





SUMMARY

The City of Guelph is a growing community. Under the planning horizon of the City’s 2014 Water Supply Master

Plan, the City’s population is expected to grow from 130,670 to 186,299 – an increase of almost 43 percent.

The Water Supply Master Plan has set an average annual day water savings target of 9,147 cubic metres per

day by 2038. To achieve this target the City will need to reduce gross per capita demands from 375 litres per

capita per day in 2038 (2014 Water Supply Master Plan projected baseline demand rate) to only 326 litres per

capita per day – a reduction of 13 percent.

The 2014 Water Supply Master Plan water savings target is based on average annual day water production

values. At this time it is assumed that water savings in the City will be distributed across the different customer

sectors with demands in each sector (residential, industrial/commercial/institutional, and non-revenue water)

declining on a per capita basis by about 13 percent between 2013 and 2038. The actual savings achieved in

each of these sectors is not critical, as long as the total reduction in production rates meets the 2014 Water

Supply Master Plan target.

The City’s water production targets include both customer demands and non-revenue water. Between 2006

and 2014 approximately 51 percent of the water produced by the City was used by residential customers, 34

percent by industrial/commercial/institutional customers, and about 15 percent was attributed to non-revenue

water.

Between 2006 and 2014 gross average annual day per capita production rates in Guelph have declined from

447 litres per capita per day in 2006 to only 353 litres per capita per day in 2014. Based on the linear trend of

production values this equates to an average reduction of 12.3 litres per capita per day per year during these

eight years.

Between 2009 and 2014 gross average annual day per capita production rates in Guelph have declined from

387 litres per capita per day in 2009 to only 353 litres per capita per day in 2014. Based on the linear trend of

production values this equates to an average reduction of approximately 6.3 litres per capita per day per year

during these five years.

Given that an average day production rate of 353 litres per capita per day was not projected until 2019, the

City is currently approximately nine years ahead of its target schedule and only 19 litres per capita per day

away from meeting its target 2038 production rate of 326 litres per capita per day.

Between 2006 and 2014 gross average annual day per capita demand rates in Guelph have declined from 379

litres per capita per day in 2006 to only 293 litres per capita per day in 2014. Based on the linear trend of

production values this equates to an average reduction of 10.4 litres per capita per day per year during these

eight years.

Between 2009 and 2014 gross average annual day per capita demand rates in Guelph have declined from 325

litres per capita per day in 2009 to only 293 litres per capita per day in 2014. Based on the linear trend of

City of Guelph





production values this equates to an average reduction of approximately 6.6 litres per capita per day per year

during these five years.

Average annual day demands in the low-density residential customer sector declined by 6 litres per capita per

day between 2006 and 2014; demands in the combined medium- and high-density residential customer sector

declined by 7 litres per capita per day per year. The overall average residential demand in 2014 was 174 litres

per capita per day – only 17 litres per capita per day higher than the 2038 residential target of 157 litres per

capita per day identified in the 2014 Water Supply Master Plan. The significant reduction in residential

demands has been the result of the effectiveness of the City’s water efficiency measures combined with

changes to the Ontario Building Code and the impact of the recent marketplace shift towards more efficient

plumbing fixtures and appliances. While the rate of decline in residential demands is expected to slow down as

the number of inefficient customers diminishes, the City is expected to meet, and likely exceed, its residential

demand target – a result that would provide a buffer should demand reductions in the

industrial/commercial/institutional customer sector or non-revenue water savings prove more difficult to

achieve than expected.

Demands in the industrial sector have almost rebounded back to 2006 levels with only a slight decrease from

10,223 cubic metres per day in 2006 to 9,944 cubic metres per day in 2014. Demands in the commercial sector

also decreased from 3,570 cubic metres per day in 2006 to 3,209 cubic metres per day in 2014. Demands in the

institutional sector (including miscellaneous accounts) decreased from 5,414 cubic metres per day in 2006 to

3,921 cubic metres per day. The total demand in the industrial/commercial/institutional customer sector

(including miscellaneous accounts) remained relatively constant during this period despite the growing

population – 17,480 cubic metres per day in 2006 and 17,052 cubic metres per day in 2014.

With a current (2014) industrial/commercial/institutional customer sector demand (based on equivalent

population) of 250 litres per capita per day and a 2038 target of 248 litres per capita per day, the City is

currently ahead of schedule to reach its industrial/commercial/institutional target.

The City’s current (2014) non-revenue water rate is below the 2038 target identified in the 2014 Draft Water

Supply Master Plan. However, because of the significant growth expected in the City by 2038, the volume of

non-revenue water expressed as a percentage of production will need to decline from the 2014 level of almost

14 percent to only 11 percent in 2038. If this level of non-revenue water savings is not achieved by 2038,

additional savings will need to be achieved in the residential and/or industrial/commercial/institutional

customer sectors to meet the City’s overall 2038 water production target as identified in the 2014 Draft Water

Supply Master Plan.

City of Guelph





REFERENCES

AECOM and Golder Associates. (2014). Water Supply Master Plan Update. City of Guelph.

Earth Tech Canada Inc., Lura Consulting, Lotowater Geoscience Consultants Ltd., C.N. Watson and Associates

Ltd. (2006). Water Supply Master Plan. City of Guelph: City of Guelph.

Fortin, M. (2013). Mining Guelph's Customer Water Meter Data. Guelph: City of Guelph.

Resource Management Strategies Inc. (2009). Water Conservation and Efficiency Strategy Update. Guelph:

Guelph.

WaterSense. (2008, May 14). Water-Efficient Single-Family New Home Specification Supporting Statement.

Retrieved from Environmental Protection Agency:

www3.epa.gov/watersense/docs/home_suppstat508.pdf

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