Transcript SB1 passed in 1997 Mandate for Statewide Water Plan

An Interregional Water Solution with
Conjunctive Use of Groundwater
Haskell L. Simon
President, Coastal Plains Groundwater Conservation District
Vice President, Region K Water Planning Group
SB1 (1997)
Mandate for Statewide Water Plan
New Era for Water Planning Based on
“Bottom Up” or “Grass Roots” Approach
Address anticipated water shortages over a
50 year period by determining:
Available water supplies
 Demands for water
 Strategies to achieve projected short falls

The Essence of the SB1 Process
Today
Before
Top Down Approach
vs.
Bottom Up Approach
SB1 Regional Approach
16 Regions in Texas

Each group represented by one or more individuals
from 11 “Interest Groups”
RWPG is responsible for preparing and
adopting a regional water plan
Regional Plans consolidated into the State
Water Plan “Water for Texas 2002”
Implementation of the Plan will require
legislative and/or regulatory action.
Regional Water
Planning Areas
Regional Planning Group Membership
(11 Interest Groups)
1.
2.
3.
4.
5.
Public
Counties
Municipalities
Agricultural
Interests
Environmental
Interests
6. Industries
7. Small businesses
8. River Authorities
9. Water Districts
10. Water Utilities
11. Electrical
Generating Utilities
Projected Urban & Agricultural
Water Uses
12
Million Acre-feet
10
8
6
Agricultural
4
Urban
2
0
1990 2000 2020 2030 2040 2050
Year
Total Water Demand by Type of Use
(2003)
Year 2060
Year 2000
Livestock
1%
Mining
2%
Municipal
21%
Irrigation
36%
Steam Electric
17%
Manufacturing
3%
Steam Electric
10%
Mining
2%
Livestock
1%
Manufacturing
7%
Irrigation
63%
Municipal
37%
Use by Source of Supply (2000)
GROUNDWATER
35%
SURFACE
WATER
65%
2050 Water Needs
SB 1 Planning Process
(entire state & border regions)
Region K
2050 Shortfalls
• 160,000 acre-feet/yr of irrigation
• Some rural communities upstream of
Highland Lakes (5,400 acre-feet/yr)
2050 Water Needs
SB 1 Planning Process
(entire state & border regions)
Region L
Bexar County shortfall
• 350,000 acre-feet/yr of municipal use
(current update to plan will reduce this amount)
Regional Cooperation Defines
Project
SB 1 Planning Process
(entire state & border regions)
Region L
(SAWS)
LCRASAWS Region K
Water
(LCRA)
Project
Regional sharing of resources to
meet future water needs
The LCRA-SAWS Water Project is designed to
meet the needs of both the lower Colorado River
basin and the San Antonio area
 The
lower Colorado River basin needs additional water
to satisfy agricultural needs, protect Highland Lake
levels and provide water for upstream rural communities
 San Antonio needs significant additional water to meet
growth and economic development needs
Project Summary
Construct off-channel reservoirs to store surface waters
Institute practices and improvements to reduce
agriculture’s demand for water
Install groundwater wells to serve agriculture’s needs
during drought
Create up to 150,000 acre-feet per year for SAWS
Meet environmental requirements
Study Period activities determine implementability and
permitting
LCRA-SAWS Water Project
Water for rural
communities
Lake
Buchanan
More stable water levels
in Highland Lakes
Austin
San Antonio
Water for San Antonio
(up to 150,000 ac-ft/yr)
Water for agriculture
Freshwater inflows for
Matagorda Bay
LCRA SAWS Water Project
P
Develop 330,000 ac-ft of water by:
1. Irrigation conservation
-Onsite and system
improvements in districts
2. Off-channel reservoirs
Wharton
3. Conjunctive use of groundwater for
agricultural needs during drought
Bay City
P
Matagorda Bay
Legislation requires that in order for the
project to proceed, the project must ...
1. Protect and benefit basin interests
2. Be consistent with the state regional water plan
3. Provide inflows adequate to maintain the ecological
4.
5.
6.
7.
health and productivity of Matagorda Bay
Maintain current instream river flow protections
Ensure that San Antonio practices stringent
conservation measures
Provide for a broad public and scientific review
process
Benefit stored water levels in Lakes Travis and
Buchanan
We are at the beginning of a multiyear, comprehensive evaluation
Technical
Study Plan
Development
2002
2004
Technical
Studies
Permitting
Permit
Review &
Submittal &
Continuation Completion of
Studies
of Studies
2007-2008
2010
Groundwater
Average of 62,000 acft per year in severe
droughts
Divert only to
Colorado basin
agricultural users
Groundwater used
only in times of
drought
Groundwater Modeling Overview
Simulate a range of withdrawals to meet agricultural
needs during drought
Evaluate impacts to groundwater/ surface water
Assess impacts of pumping on groundwater quality
Assess uncertainty with model predictions
Groundwater Study Objectives
Determine if additional groundwater can be developed
without substantially affecting the current groundwater
users and evaluate:
Potential mitigation techniques for users, if affected
Saline water encroachment from the coast.
Land surface subsidence
Induced migration of poor quality native groundwater
that could result from increased groundwater use
Comprehensive Groundwater
Evaluation
Defines consequences of conjunctive use
Identifies mitigation needs and options
Uses more data and performs more data analyses
than the GAM
Predictions will contain confidence limits based
on uncertainty associated in calibrated model
Model will be developed at the spatial resolution
supported by the data

0.1 to 0.5 mile variable grid anticipated
Stay tuned . . .