The Colorado River Diversion Option is an important part of the South Central Texas (Region L) Regional Water Plan that was adopted by the SCTRWPG on January 4, 2001. The strategy is included in the Adopted Regional Water Plan with an associated dependable water supply of 150,000 acft/yr for Region L. However, the SCTRWPG acknowledges potential revisions in the dependable supply for this strategy pursuant to the TWDB review of March 28, 2001. The following discussion includes: (1) Background information; (2) Acknowledgement of the possibility that the quantity available may be only 131,000 acft/yr; (3) Recognition of Memorandum Contract between SAWS and LCRA; (4) Recognition of HB 1629, 77th Texas Legislature; (5) Description of a potential reduction of 19,000 acft/yr in the dependable supply for the Regional Water Provider(s) for Bexar County; and (6) Discussion of cost implications of this potential reduction in dependable supply.
(1) Background information summarizing estimates of dependable supply based on LCRA Management Plan and Consensus Environmental Criteria. The South Central Texas (Region L) and Lower Colorado (Region K) Regional Water Planning Groups (RWPGs) included the Colorado River Diversion Option in their respective Initially Prepared Regional Water Plans pursuant to descriptive information prepared by the Lower Colorado River Authority (LCRA) and presented to the South Central Texas RWPG on July 6, 2000. LCRA descriptive information indicated that planned implementation of the Colorado River Diversion Option subject to instream flow requirements consistent with the LCRA Management Plan would result in a dependable supply of up to 150,000 acft/yr for water user groups in Region L. Region K included the water management strategy at 150,000 acft/yr and Region L included the strategy in two parts, as follows: (a) Up to 18,000 acft/yr to be diverted near Bastrop for delivery to Hays County; and (b) Up to 132,000 acft/yr to be diverted near Bay City for delivery to Bexar County. Subsequent technical analyses of this water management strategy subject to statistically-based instream flow requirements outlined in the Consensus Environmental Criteria were completed by the LCRA resulting in an estimated dependable supply of 131,000 acft/yr for water user groups in Region L.
(2) Acknowledgement of possibility that the quantity of water available to water user groups in Region L from the Colorado River Diversion Option (LCRA) water management strategy may range between 131,000 acft/yr and 150,000 acft/yr. The potential difference in quantities of water available from the LCRA to meet Region L needs depends upon applicable environmental requirements, which cannot be determined without additional research. Such research is being undertaken as noted in Points Number (3) and (4) below. Pursuant to TWDB review, Region L acknowledges that this water management strategy may involve delivery of 113,000 acft/yr (rather than 132,000 acft/yr) from the Colorado River near Bay City to Bexar County. The portion of this water management strategy involving diversions from the Colorado River near Bastrop to Hays County (18,000 acft/yr) is assumed to remain unchanged.
(3) Region L Recognition of the Memorandum Contract between SAWS and LCRA effective February 7, 2001. The Memorandum Contract states in its recitals, among other things, that: “LCRA desires to sell and SAWS desires to purchase surface water to be made available from demand reduction and new firm yield to be developed from the Colorado River consistent with the regional water plans for Region K and Region L (“Project”) if feasible and if legislation (the “Legislation”) is enacted by the 77th Texas Legislature during its Regular Session to allow the purchase and sale of water on terms consistent with this Memorandum Contract.” The Memorandum Contract includes the following specific provisions:
a) Maximum of 150,000 acft/yr sale of surface water; and
b) Seven year study period to determine if water can be made available cost-effectively while addressing potential environmental impacts.
The SCTRWPG believes that the Colorado River Diversion Option (LCRA) as presently included in the Region L and Region K Plans is consistent with this Memorandum Contract.
(4) Region L Recognition of HB 1629 of
the 77th Texas Legislature effective May 3, 2001. HB 1629,
enacted by the 77th Texas Legislature, Regular Session, and
mentioned in the Memorandum Contract described in Point Number 3 as the
“Legislation” is entitled, “AN ACT relating to the provision of water by the
Lower Colorado River Authority to a municipality outside the Colorado River
Basin.” HB 1629 includes the following
specific provisions:
a) Contractual sale of no more than 150,000 acft/yr of water;
b) Provisions for instream flows no less protective than those in the LCRA Water Management Plan approved by TNRCC; and
c) Consistency with Regional Water Plans filed with TWDB on or before January 5, 2001.
In addition, HB1629:
a) Sets a base period for contracts of 50 years, with an option to renew for no more than an additional 30 years, with requirements that, if contracts are renewed, the municipality progressively reduces the quantity of water used during the last 10 years of the renewal term;
b) Provides for a surcharge to enable the LCRA to develop and manage water resources for the mutual benefit of the LCRA’s service area and the municipality;
c) Ensures that the municipality will prepare a drought contingency plan, and has developed and implemented a water conservation plan that will result in the highest practicable levels of water conservation and efficiency achievable within its jurisdiction;
d) Provides for a broad public and scientific review process to ensure that all information that can be practicably developed is considered in establishing beneficial inflow and instream flow provisions; and
e) Provides that the contract must benefit stored water levels in the LCRA’s existing reservoirs.
The SCTRWPG believes that the Colorado River Diversion Option (LCRA), as presently included in the Region L and Region K Plans, is consistent with HB 1629.
(5) Description of a potential reduction of 19,000 acft/yr in the dependable supply for this water management strategy assigned to the Regional Water Provider(s) for Bexar County and reflection of it in the Exhibit B tables. In the Region L Adopted Regional Water Plan, the Colorado River Diversion Option (LCRA) includes up to 132,000 acft/yr of water to be diverted at Bay City and delivered to Bexar County. The supply would be phased into use to meet the projected needs of customers of the Regional Water Provider(s) for Bexar County, with 66,000 acft/yr being needed in 2020, and the additional 66,000 acft/yr being needed in 2030, 2040, and 2050. If the LCRA source of supply is revised to a total of 131,000 acft/yr (rather than 150,000 acft/yr), the supply to Bexar County could be revised to 113,000 acft/yr, resulting in 66,000 acft/yr being available to the Regional Water Provider(s) in 2020, and only an additional 47,000 acft/yr (19,000 acft/yr less) being available in 2030, 2040, and 2050. The effects of such potential revisions upon the Total New Supplies and System Management Supply (Municipal, Industrial, Steam-Electric, & Mining) for Bexar County (Vol. I, page 5-25) are summarized below.
Description
2030 2040 2050
Colorado River Diversion Option (LCRA)
Adopted Plan (acft/yr) 132,000 132,000 132,000
Potential Revision (acft/yr) 113,000 113,000 113,000
Difference (acft/yr) 19,000 19,000 19,000
Total New Supplies
Adopted Plan (acft/yr) 467,058 529,104 567,862
Potential Revision (acft/yr) 448,058 510,104 548,862
Difference (acft/yr) 19,000 19,000 19,000
System Management Supply
Adopted Plan (acft/yr) 185,852 190,458 187,477
Potential Revision (acft/yr) 166,852 171,478 168,477
Difference (acft/yr) 19,000 19,000 19,000
The potential revised dependable supply associated with the Colorado River Diversion Option (LCRA) is assigned to the City of San Antonio and/or the San Antonio Water System (SAWS) in Exhibit B Tables 11, 12, and 13 and footnoted accordingly. Exhibit B Tables have been submitted to the TWDB in electronic format.
(6) Discussion of the cost implications of this potential reduction in dependable supply. With modification of transmission facilities to deliver a reduced dependable supply of 113,000 acft/yr, the annual cost of this water management strategy could decrease by about $11 million per year (8.4 percent) and the unit cost of this water management strategy could increase from about $1,016 per acft to about $1,087 per acft (7.0 percent). This potential revision could increase the overall unit cost of water obtained through the development of multiple water management strategies by the Regional Water Provider(s) for Bexar County could increase by up to $22 per acft (2.8 percent). Due to the small potential effects, costs presented in the Regional Water Plan and the Exhibit B tables are not changed.