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Newport News Waterworks
Impact of Climate
Change on Water
Supplies of Coastal
Communities
Brian L. Ramaley, P.E.
Director, Newport News Waterworks and
President, Association of Metropolitan
Water Agencies (AMWA)
World Water Week
21 August 2008
AMWA – Leaders in Water
 Comprises the largest publicly owned U.S.
metropolitan water systems
 Members provide drinking water to over 127
million people in the U.S.
 Focus on the U.S. Congress, the Administration
and Management Issues facing metropolitan
water suppliers.
 New focus: Climate Change and International
Outreach and Knowledge Exchange.
AMWA’s International Involvement

Expand and enhance AMWA's value to US metropolitan
drinking water utilities through access and engagement
with similar metropolitan utilities in other countries.
Exchange experience and knowledge with utility managers
abroad and to provide opportunities for peer-to-peer
exchange of ideas and skills.

International knowledge exchange on climate change
matters is of greatest importance.
Presentation Outline
 Background on Newport News Waterworks
 Specific Impacts of Climate Change
 Conclusions for the Future
Newport News Waterworks
 Municipally owned system that serves
drinking water to more than 400,000 people
 3 cities, two counties, many military bases
 Mid-Atlantic location at mouth of Chesapeake
Bay
 In coastal plain, average elevation < 10 meters
Newport News Climate Information
Month
Avg. High Avg. Low
Mean
Avg. Precip
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
47°F
49°F
57°F
66°F
73°F
81°F
85°F
84°F
78°F
68°F
60°F
51°F
39°F
42°F
49°F
57°F
66°F
74°F
79°F
77°F
72°F
61°F
52°F
44°F
4.08 in.
3.60 in.
4.73 in.
3.35 in.
4.03 in.
3.44 in.
4.86 in.
4.74 in.
4.84 in.
3.45 in.
3.35 in.
3.43 in.
32°F
34°F
41°F
49°F
58°F
67°F
72°F
71°F
65°F
53°F
44°F
36°F
Newport News - Location
Atlantic Ocean
Virginia
Newport News
North Carolina
Newport News, VA Waterworks
System and Water Sources
 Interconnected pumped storage reservoirs
and one river intake
 Chickahominy River is major water source
 Surface water ----- 57 mgd safe yield based on
75-year record
 Groundwater desalination ----- 6 mgd yield
–
1 mgd = 3,785 cubic meters per day
–
10,000 cubic meters per day = 2.64 mgd
Chickahominy River/Intake
Brackish Groundwater Desalting
Climate Change Impacts to Coastal
Water Supplies
 Warmer temperatures
 Changing precipitation patterns
 Rising sea level
Warmer Temperatures
 Higher evaporation/lower yield
 Higher demand
 Increased biological activity and impacts on
water quality/treatability
Changing Precipitation Patterns
 More intense rainfall events/storms
–
Increased turbidity/sediment/treatment required
–
Faster reservoir refill – shoreline erosion
–
Spillways must pass more water
–
Storm damage to facilities – redundancy/reliability
issues?
 More frequent, intense or prolonged droughts
–
Higher irrigation demand
–
Reduced surface system yields during drought
–
Reduced groundwater recharge/yield
Rising Sea Level
 Inundation of service area
 Surge impacts to low lying areas during
storms including water utility facilities are
magnified
 Salt water intrusion into surface supplies
 Salt water intrusion into groundwater
 Accelerated subsidence
Summary of Historical Drought
Studies: Newport News
 Water supply planning in Eastern U.S. is
typically based on most severe drought in
20th Century (e.g., 1930)
 Firm Yield of 57 mgd for 78-year streamflow
record estimated for surface system based on
1930-2008 record
Fort Monroe
Constructed Between 1819 and 1834
Updating Drought Studies to Include
19th Century Records
 Monthly rainfall records extend back to 1836
for Southeastern and Central Virginia
 Standardized Precipitation Index (SPI)
method was used to compare 19th and 20th
Century rainfall records
 Synthesized streamflows developed from
rainfall records
 Performed Firm Yield modeling with a 161-
year streamflow record
Rain Gauge Locations
Richmond, 1872-1998
Powhatan Hill, 1849-1876
Fredericksburg, 1893-1998
Williamsburg, 1900-1998
Hopewell, 1888-1998
Hampton, 1869-1913
Fort Monroe, 1836-1890
Newport News, 1899-1927
Norfolk, 1871-1998
19th and 20th Century Rainfall Data
Show Similar Means and
Distributions
Monthly Rainfall (inches)
20
15
10
5
0
Monthly Rainfall Datasets
Results of Firm Yield Modeling with
161-Year Streamflow Record
 Four 19th Century droughts are more severe
than the worst 20th Century drought
 Minimum Firm Yield is 42 mgd (1851-55 drought)
 20th Century drought of record (1930):
57-mgd Firm Yield corresponds to a
22-year return period (rather than a 75-year
return period)
 Firm Yield for a 75-year return period is
44.5 mgd
Implications for Water Supply
Planning Studies
Consideration of 19th Century droughts can
significantly change evaluations of existing
system reliability and future needs.
Recent droughts and storms indicate a return
to precipitation conditions in the mid-Atlantic
region more like the 1800s than the 1900s.
Are the 1800s a better model for climate
change impacts with respect to yield?
Newport News Response Curves
position analysis
New port New s Waterw orks using 53 mgd average annual raw w ater demand
100
90
useable capacity (in %)
80
70
60
50
40
5% risk of depleting useable capacity
10% risk of system depletion
161 year simulated average
1930 drought, year 1
2002 actual
30
20
10
0
jan
feb
march
apr
may
june
july
simulation month
aug
sept
oct
nov
dec
Distribution of possible "safe yields"; 1838-2001
110
100
yield in mgd
90
80
70
60
1884-86 yield; 95% reliability
50
1863-66 yield; 98% reliability
40
30
0%
10%
20%
30%
40%
50%
60%
probability of storage depletion
70%
80%
90%
100%
Estimated Sea Level Rise at NN – 3 to 4 mm/year
Relative Sea Level Rise Along the
East Coast of North America
From Zhang et al. (2004) Climatic Change 64: 41–58.
Hurricane Isabel
Sep 18-19, 2003
Reagan Washington
National Airport
Chesapeake Inundation
Prediction System (CIPS)
SLR 2008
SLR 2050
SLR 2075
SLR 2025
SLR 2100
Hampton Roads Inundation
Estimates Under Different
Sea Level Rise Scenarios
Extent of flooding is a function of:
- height of water
- land elevation
- land relief
With increasing sea level, additional
flooding from storm surge effects will
be greater than previously
- smaller storms will have equivalent
destruction potential as larger storms
pre-SLR
Important implications for both human
populations as well as living resources
and coastal environments
From Titus and Wang (2008) EPA.
Conclusions for the future
 Climate change will impact coastal water
supplies in multiple ways
 Regional modeling and downscaling of global
models are needed to predict temperature, sea
level rise, design storms and droughts
 Combination of impacts must be considered
 Existing yields and safety factors are almost
certainly wrong – high or (more likely) low
Conclusions for the future
 Diversification of water supplies will enhance
reliability – Security Through Diversity
 Looking further back in time may be a useful
way of estimating the future climate
 Integrated resource planning principles offer a
roadmap
 Redundancy/reliability concerns should be
given more attention in the face of an
uncertain future