Transcript Drinking water

Wet and dry.
Urban water management issues in the
Western United States and Canada
Frédéric Lasserre
Laval University
Drinking water: what costs, with what
resources?
Producing drinking water, distribute it, collect and treat
used water: major municipal responsibility.
Social stakes are enormous:
• 1 billion people have no access to safe water
• Water increasingly polluted
• Infrastructure to build or renovate : major investment
• Regulations on drinking water are more and more severe
(at least in developed countries)
 Resource management issue (quantity, quality)
 Public finance issue
www.unep.org/dewa/vitalwater
1. Access to the resource
• Domestic use are usually small compared to
industrial or agricultural use (withdrawal and
consumptive use)
• City = major concentration of people
• Total demand may thus be significant and
spatially very concentrated
=> Problem of security of supply
Even in Antiquity, the issue of urban water supply was significant, with
for instance the construction of aqueducts
Source : archeolyon.com
Issues of resource protection and resource sharing
www.grida.no/graphic.aspx?f=series/vg-water2/0231-competionurb-rur-EN.jpg
2. Access : the case of
Western
American cities
Los Angeles, San Francisco,
Las Vegas, Phoenix : coping
with dry climates.
Las Vegas : 12 cm of rain/yr
Domestic use of the water :
less than 15% of total water
use in the West (agriculture:
75%)
Often blamed for water problems : fountains and hotels in Las Vegas
Pictures: F. Lasserre
Evolution of population of selected American States (million)
1970
1980
1990
2000
2009
2012
Nevada
0,49
0,8
1,2
2
2,6
2,76
New
Mexico
Utah
1,02
1,3
1,52
1,82
2
2,09
1,06
1,46
1,72
2,23
2,8
2,86
Arizona
1,77
2,72
3,67
5,13
6,6
6,56
Colorado
2,21
2,89
3,3
4,3
5
5,19
Florida
6,79
9,75
12,94
16
18,5
19,3
California
19,95
23,67
29,76
33,9
36,9
38
-> a very fast
expanding
population; now
stopped or much
slower
-> concentration
of large demand
in specific places
Lasserre and Descroix 2012
… with a peculiar urban model
Las Vegas, 1984 and 2011
Landsat images
Albuquerque, NM
Urban sprawl and
individual house-based
urbanism
-> cost of infrastructure
-> lot of outdoor use of
water
Lasserre
Las Vegas, NV
http://wrldtvler.files.wordpress.com/2010/06/img_5249.jpg
Water use in Southern Nevada, 2007, %
Irrigation (mainly golf courses)
Industry
Retail trade
Public Institutions (government,
schools, hospitals)
Hotels
Residential
Others
7,6
1
13,4
5
6,3
59
7,7
Southern Nevada Water Authority, 2009 Water Resource Plan, Las Vegas, 2009, p.16
In urban water use, hotels, retail and industry are often marginal
users.
Hotels : tight regulations. Recycled water.
Main user : residential.
Idea: specifically target this segment
3. Policies : how did cities secure access to the
resource?
Need to secure reliable access.
Groundwater.
Massive water schemes:
Las Vegas: Lake Mead
Phoenix : Lake Havasu, Salt River
San Francisco : Hetch Hetchy Canal
Los Angeles : Los Angeles Aqueduct
San Diego : Colorado River Aqueduct
Hoover Dam on the Colorado,
creating Lake Mead
Lasserre
Central Arizona Project (CAP), Phoenix.
Lasserre
Massive water diversions, California
Local project
State project
Federal project
Central
Valley
Project,
1950s
State Water
Project:
California
Aqueduct, 1960s
www.aquafornia.com/where-does-southern-californiaswater-come-from/
Los Angeles Aqueduct,
1913
(prolonged to Lake
Mono, 1940)
Colorado River Aqueduct,
1941
All American
Canal, 1940
Colorado : a river now
completely transfered,
dammed and harnessed
But tough competition with
agriculture
-> Legal system of prior
appropriation
Groundwater decline
Resource not infinite
-> Need to control demand
Several tools designed to encourage conservation by residents
Education and communication
Fiscal :
-
Rebates on water bill for xeriscaping and drip irrigation
Rebates on dual flush/low flush toilets
Rebates on low-water use appliances
Rebates on special car wash
Regulation :
-
Regular washing garage alley or car forbidden
Daytime watering prohibited
Summertime watering regulation
Emergency regulation during drought
Water police
Tarification :
- Incremental and progressive tarification.
Cheap basic service : for 50 l/pers/day, family of 4 : 5 $/month
Bill increases and can reach up to 300 $/month
Despite this, water supply very tight ; drought since 2010…
Xeriscaping
(SNWA)
3. Urban Water management in Canada : the land of
plenty ?
2005
3.1. Water use
structure
Consumptive use (2006) :
Agriculture 57%
Industrial 20%
Thermoelectric 14%
Residential 9%
Environment Canada
Again, residential use often
represents bulk of municipal
use
But what’s the problem in
Canada ?
Average value masks diversity of local situations
3.2. Scarce water in Canada?
Water is overall abundant in Canada, however :
• Dryer regions, like the Prairies
• Recurrence of dry summers lately (climate change)
• Vulnerability of the domestic segment, main user of
urban water in Canada
• Cost of producing and treating a lot of water
• Demand increase forces the construction of new and
costly plants for drinking water production and used
water treatment
– Peaks : pool fill-up in April; summer watering (again,
outdoor use…)
– impacts of climate change on sewers (unitary -> need
for dual system; urban planning to be reviewed, at a
cost)
• Increasing investments because of the pollution of the
resource – agriculture, industrial, municipal
 Production of drinking water: in Québec, no political will
to apply principle of polluter-payer … about to change? Law on
water 2009
• Legislation introduces tighter regulations and norms on
drinking water
 Financial responsibility rests on municipal governments…
Occasional scarcity of water, going to happen more
often in summer with climate change: real
problem, but over short periods.
Depends also on use habits.
The fundamental problem for cities is:
 fiscal (principle of consumer-payer), and of
 public finances : who pays for the production,
treatment and distribution systems
 much more than increase of volume
Idea of water tarification to finance
production and manage demand expansion
3.3. In Canada, what tarification ?
• 100 % of Canadians pay for their water
• 55% pay with a non-incentive tarification :
– 43% : fixed tariff included in municipal taxes
– 12% : decreasing volumetric tarification
• 45% pay with an incentive tarification :
– 36% : flat volumetric rate
– 9% : progressive tariff
• In 1999, consumption was 70 % higher when there were
flat monthly rates than where tariffs were based on
used volume.
1998.
Environment Canada, 2012
Pricing water : a difficult policy to
implement
•
•
•
•
Cost of installing meters (± 300 M $ only in Québec)
Door opened to privatization ?
Issue of minimal basic water use.
Necessity to have a price structure high enough to be
incentive. How is it possible to legitimize it…
– If the problem is about public spending in nature, and not resource
management
– And if the production of drinking water not very costly (between 23
and 55¢/m³ with infrastructure depreciation)?