1.1 Current
Upper Basin Supplies
1.2 Comprehensive
Sabine Watershed Management Plan
2.4 Summary
of Additional Water Supply Needs
3.0 Alternatives
to Meet Identified Shortages
3.2 Pipeline
From Toledo Bend Reservoir
3.4 Temporary
Use of Lake Cherokee Water Supply
3.5 Temporary
Use of Dallas Lake Fork Supply
3.6 Use
of Dallas Lake Fork In-Basin Supply
3.7 Pipeline
from Lake Fork to Lake Tawakoni
3.8 Additional
Water Delivery Costs
List of Tables
Table 1. SRA Upper Basin Demands by Customer Type (MGD)
Table 2. SRA Upper Basin Demand by Geographic Area (MGD)
Table 3. Firm Yield of Lake Tawakoni and Lake Fork (acre-feet per year)
Table 4. Firm Yield of Lake Tawakoni and Lake Fork (MGD)
Table 5. SRA Upper Basin Yield Under Various Scenarios (acre-feet per
year)
Table 6. SRA Upper Basin Yield Under Various Scenarios (MGD)
Table 7. Additional Supplies Needed for Demand Scenarios (MGD)
Table 8. Prairie Creek Reservoir Cost Summary
Table 9. Toledo Bend Pipeline Alternatives
Table 10. Toledo Bend Pipeline Alternatives Cost Summary
Table 11. Proposed Groundwater Wellfields
Table 12. Potential Use of Dallas Lake Fork Supplies (MGD)
Table 13. Lake Fork to Lake Tawakoni Pipeline Summary
Table 14. Additional Customer Facilities
Table 15. Summary of Additional Supply Needed (MGD)
Table 16. Comparison of Long-Term Supply Alternatives (MGD)
List of Figures
Figure 1. SRA Upper Basin Supply and Demand
Figure 2. Lake Fork Reservoir Storage Under Various Operations
Figure 3. Lake Tawakoni Reservoir Storage Under Various Operations
Figure 4. General Pipeline Routing.
Appendix
Appendix A. Upper Basin Customer Demands
Appendix B. Upper Basin System Yield Analysis
Appendix C. Prairie Creek Reservoir
Appendix D. Upper Basin Pipeline Analysis
Appendix E. Upper Basin Groundwater Analysis
In May 2002, the Sabine River Authority of Texas (SRA) authorized KBR to update and expand investigations of various methods and costs for supplying future water needs in the Upper Sabine Basin. This report documents the analysis of SRA demands in the Upper Basin and summarizes the alternative supply strategies that were investigated for meeting those demands through year 2050.
Key Findings
The key findings associated with this study are summarized below:
·
Currently,
existing water supplies available to the SRA in the Upper Basin include the SRA
allocations of Lake Tawakoni and Lake Fork. The yield in these reservoirs is
anticipated to decrease in the future due to sedimentation.
·
The
Upper Basin is expected to have demands for water from SRA that exceed the
current SRA supply within the next 10 to 20 years.
o Demand Scenario No. 1. Demands associated with existing SRA contracts
and requests for additional supplies, year 2050 new supply needed: 42.5 MGD.
o Demand Scenario No. 2. Demands associated with existing SRA contracts
and requests for additional supplies and additional needs identified by Senate
Bill 1 Regional Planning, year 2050 new supply needed: 83.4 MGD.
·
A
system yield permit that includes Lake Fork, Lake Tawakoni, and Toledo Bend
Reservoir with upstream diversions to the Longview / Kilgore / Henderson area
would provide 4 MGD (Million Gallons per Day) of additional supply under
projected (conservative) 2050
sedimentation conditions. The Texas Commission
on Environmental Quality’s permitting process encourages system yield permits.
·
Short-term
Supply Alternatives
o Lake Cherokee. No
additional supply available under its current operation.
o Dallas portion of Lake Fork. Dallas is not expected to use its full
allocation of Lake Fork water until 2018. This alternative provides the
potential to delay construction costs associated with any of the following long‑term
supply alternatives, but has considerable contracting issues to resolve between
SRA and the City of Dallas.
·
Long-term
Supply Alternatives
o Water Conservation. Water conservation is an integral element of
SRA’s commitment to provide adequate supplies of high-quality water to
municipal, industrial, agricultural, and recreational users of Sabine Basin
water. Water conservation is accounted
for in the demand projections used in this study.
o Dallas “In-basin“ Portion of Lake Fork. According to the Lake
Fork water right, 10.6 MGD of the Dallas allocation cannot be transferred out
of the Sabine Basin. This supply could be acquired by SRA through contractual
negotiations and used in the Upper Basin.
This supply could also be reserved to maintain lake levels in Lake Fork
for recreational uses. There are significant contracting issues to resolve
between SRA and the City of Dallas before this water can be considered a viable
option for meeting future demands.
o Groundwater Development. The Senate Bill 1 Regional Plans
identify approximately 45 MGD of potential available supply in the Carrizo
Wilcox Aquifer upstream of the Longview/Kilgore/Henderson area. There are
significant issues that must still be addressed before groundwater can be
considered a viable option for meeting future demands. These issues include water quality, impact
on surrounding well performance, and regulatory issues.
o Prairie Creek Reservoir. The maximum reservoir yield of 26.5 MGD
(reservoir with high-flow scalping diversions) is not sufficient to meet either
of the year 2050 Upper Basin demand scenarios.
o Toledo Bend Reservoir Pipeline. A pipeline conveyance
project from existing supplies in Toledo Bend Reservoir can be implemented in
stages to meet increasing demands through 2050. This project provides flexibility for construction dates of
segments to be adjusted to meet a variety of potential future demands.
·
To
meet projected year 2050 demands, Prairie Creek Reservoir, groundwater
development, and/or a pipeline from Toledo Bend Reservoir will be needed.
·
The
only alternative that alone can meet the needs associated with the two demand
scenarios is a pipeline from Toledo Bend to the Longview/ Kilgore/Henderson
area along with a pipeline from Lake Fork to Lake Tawakoni.
·
Regardless
of which identified short or long-term supply alternative is selected by SRA,
there will remain a projected need to deliver water from Lake Fork to Lake
Tawakoni by year 2015.
Analysis of Demand and Existing Supply
A survey was performed by the SRA of its existing customers, entities that have requested water from SRA, and other retail water suppliers in the Upper Basin. SRA Upper Basin demands have been grouped into two categories: 1) Existing Contracts and Requests; and 2) Existing Contracts, Requests and Additional Demands from Regional Planning.
Existing supplies available to the SRA in the Upper Basin include the SRA allocations of Lake Tawakoni and Lake Fork. The yield in these reservoirs is anticipated to decrease in the future due to sedimentation. Table ES-1 and Figure ES-1 summarize the supplies, demands, and need for additional supplies in the Upper Basin.
Table ES-1. Additional Supplies Needed for Demand Scenarios (MGD)
|
|
Permitted |
2000 |
2005 |
2010 |
2020 |
2030 |
2040 |
2050 |
|
SRA Lake Tawakoni Supply |
42.5 |
42.5 |
42.4 |
42.2 |
41.9 |
41.5 |
41.2 |
40.9 |
|
SRA Lake Fork Supply |
50.7 |
46.2 |
45.8 |