Transcript WATER, WATER WHERE?? With apologies to SAMUEL TAYLOR COLERIDGE author “The Rhyme of the Ancient Mariner” December 5, 2006

WATER, WATER
WHERE??
With apologies to
SAMUEL TAYLOR COLERIDGE
author
“The Rhyme of the Ancient Mariner”
December 5, 2006
Waterworks Board
Corporation
Controller
Director, Contracts and Operations
Advisory
Counsel
SAB
Legal Support
Fiscal Support
Operations oversight
CAG
TAG
•Contracts
•Budget
•Approve plans
•Opinions
•Fiscal monitor
•Approve programs
•Engage
outside
counsel
•Planning
•Receive reports and operational deliverables
•Audit
•Evaluate incentives
•Water District activity coordination
Note: Responsibilities list represents highlights of effort
Objective
• Is there an “industry standard” or guidance for
how much water supply is “enough?”
• There are many differing opinions on what is
considered enough, ranging from:
– Supply supported by the overall yield under 10-year
drought conditions to meet average daily demand
projected for 20 years; to
– Enough water to withstand a 50-year drought and
meet average demand projected for 50 years; to
– Enough water to withstand a 100-year drought and
meet maximum day demand projected for 50 years;
to
– What is vaguely described in ‘10 States Standards’.
IW Growth Policy
• Offer water (retail, wholesale, agreement)
within IURC-approved rate structure
• Offer services to “by-passed” areas
• Coordinate with communities affected by
providing or extending water services
• Provide for water supply consistent with
projected needs of central Indiana
Reference: Adapted from the Indianapolis Department of Waterworks Growth Policy, 030602
Definition: Water Supply
• Volumetric supply availability shouldn’t be confused with
supply capacity. Capacity is usually targeted at maximum
day demand plus ten percent reserve. (SD)
• Varies widely, dependent on a number of factors (EM):
– By community;
– Climate;
– How diverse the local supply mix is (i.e. vulnerability to
shortage);
– How much "reliability" is affordable;
– What the economic effects of shortages would be;
– Risk tolerance;
– Development community angst/pressure;
– Etc. (EM)
Planning Challenges 2002
• Insufficient Rated Treatment Capacity to Meet
Peak Demand Conditions
• Lack of Sufficient Potable Water Storage
– Projected Deficit
• Lack of Dependable Supply & Treatment
Capacity to Meet Long-Term Demand
– Projected Deficit
METRICS ADOPTED
by
IW BOARD MAR 06
• Achieve peak day demand 99% of time
• Have storage capacity at 50% of daily
average volume
• System pressure minimum 20 PSI with 30
PSI goal
Groundwater Availability
Generalized Aquifer
Production Capacity
Source: IDNR
Water Production Facilities
TERRY AIRPORT
Indianapolis Water Service Area
Planning Horizon
• Generally, no clear preference for a specific planning
horizon; 50 to 100 years is a reasonable timeframe.
• As for safe yield, the most common criteria is the 100-
year drought, but some agencies may require a drought
of record.
• State agencies often dictate what is appropriate to use
for safe yield analysis and planning horizons, as they
have often developed a water management program
that defines "critical use areas" or similar designations
that warrant source evaluations and demand
management, together with consideration of
environmental requirements such as minimum in-stream
flows.
Month
tem
be
r
Oc
to
be
r
No
ve
m
be
r
De
ce
m
be
r
Se
p
Au
gu
st
Ju
ly
Ju
ne
M
ay
Ap
ril
M
ar
ch
Ja
nu
ar
y
Fe
br
ua
ry
Avg Daily Consumption (MGD)
Consumption Trends
200
175
150
125
100
75
50
5-yr Avg
1999
2002
2004
25
0
More Than one Potential Additional
Source of Water
Teays Aquifer
Wabash River Aquifer
Tippecanoe County
Mid. Wabash
Reservoirs
Waverly
Aquifer
River Road Aquifer
Big Blue River Aquifer
Shelby County
East Fork White River Aquifer
Bartholomew County
Lake Monroe
Monroe County
Paragon
Aquifer
Brookville Reservoir
Wabash
River
Aquifer
Transmission
Route 2
Along Railways
~ 71 miles
Route 1
Along US-52 & I-65
~ 66 miles
White River
WTP
Route
Transmission
White River
WTP
Source:
Brookville
Lake
~74 miles
Supply Estimate Considerations
• A geometry-based estimate may
•
•
grossly underestimate the
available storage from a
reservoir
When modeled, the Geist
Reservoir was determined to
have 487 days storage, as
compared to 161 days
(estimated using a geometric
approach)… 3 times the storage
If we apply the same factor to
Morse Reservoir, supply can be
estimated to last 111 – 183 days
Geist Reservoir Volume
Geist Reservoir Dimensions
1,900
1,800
1,700
1,600
1,500
1,400
5%
Surface Area (acres)
1,300
25%
100%
1,200
1,100
1,000
900
800
700
600
500
400
300
200
100
0
0
300
600
900
1,200
1,500
1,800
2,100
2,400
2,700
3,000
3,300
Volume (MG)
3,600
3,900
4,200
4,500
4,800
5,100
5,400
5,700
6,000
6,300
Geist Reservoir Simulation
Geist Reservoir
Simulated
Storage
mgd Average
Demand)
(25% unusable
reservoir
volume,
29.3History
mgd (29.3
demand,
5 mgdWTP
minimum
stream
(With 5 mgd Minimum Release from Keystone Dam)
flow)
6,500
Full
6,000
5,500
Remaining Storage (MG)
5,000
4,500
4,000
3,500
3,000
2,500
2,000
“Empty”
1,500
1,000
487
days
500
0
Oct-33 Apr-34 Oct-34 Apr-35 Oct-35 Apr-36 Oct-36 Apr-37 Oct-37 Apr-38 Oct-38 Apr-39 Oct-39 Apr-40 Oct-40 Apr-41 Oct-41 Apr-42 Oct-42 Apr-43 Oct-43
1933
1943
Geist Reservoir – Fall Creek System
Raw Water Yield Estimates
Geist Reservoir - Fall Creek System: Raw Water Safe Yield Estimates
38
36.7
37
36.1
36
35.5
34.8
35
Safe Yield (mgd)
34.2
34
33
31.9
32
31.3
30.6
31
30.0
30
29.3
29
28
0
5
10
15
20
Unusable Volume Assumption (% of Total)
No Minimum Release from Keystone Dam
5 mgd Minimum Release from Keystone Dam
25
Geist Reservoir – Fall Creek
Surface Water System
Geist Reservoir
Fortville
Dam
USGS stream gage
03352200
Fall Creek
WTP
Millersville
USGS stream gage
03352500
Keystone Dam
USGS
stream gage
03351500
Geist Reservoir – Fall Creek
Surface Water Balance Model
Precipitation
from entire
drainage area
Precipitation
from entire
drainage area
Flow from
Mud Creek
into Fall Creek
Flow to
Fall Creek
WTP
Fall Creek Flow
(Millersville Gage)
Geist Reservoir
Fall Creek Flow
(Fortville Gage)
Geist Reservoir Supply Estimate
• Approach 1 –
•
Geometry
Assumes
– No inflow to reservoir
– 29.3 mgd demand
• 161 days
• Approach 2 – Model
• Assumes
– Simulated drought
conditions with regard
to precipitation and
evaporation
– 29.3 mgd demand
• 487 days
WTP Capacity During Drought
New
Existing
= Yield – WTP
WTP
Capacity
Capacity
New
= 1.31 x 29.3 – 32
WTP
Capacity
New
= 6.4 mgd
WTP
Capacity
Assumes: drought of record, 25% unusable reservoir volume, no groundwater use