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HomeMy WebLinkAbout08 COOPERATIVE AGREEMENT WITH IRVINE RANCH WATER DISTRICT• Agenda Item 8 n ~ AGENDA REPORT Reviewed: City Manager Finance Director MEETING DATE: OCTOBER 19, 2010 TO: DAVID C. BIGGS, CITY MANAGER FROM: DOUGLAS S. STACK, DIRECTOR OF PUBLIC WORKS/CITY ENGINEER SUBJECT: APPROVE THE TERMS AND CONDITIONS, AND AUTHORIZE THE PREPARATION OF A COOPERATIVE AGREEMENT WITH THE IRVINE RANCH WATER DISTRICT FOR THE WELLS 21 AND 22 DESALTER PROJECT SUMMARY Staff recommends that the City of Tustin enter into a Cooperative Agreement with the Irvine Ranch Water District (IRWD) for the Wells 21 and 22 Desalter Project. The purpose of this agreement is to establish a framework and methodology to quantify and mitigate the groundwater production impacts on the City of Tustin facilities associated with increased production from Wells 21 and 22. An outline of the terms and conditions of the Cooperative Agreement has been negotiated with IRWD staff and is attached. RECOMMENDATION It is recommended that City Council approve the terms and conditions, and authorize the preparation of a cooperative agreement with the Irvine Ranch Water District for the Wells 21 and 22 Desalter Project, subject to final Council approval. FISCAL IMPACT All cost will be borne by IRWD and will be determined by the extent of impacts from the project determined under the Cooperative Agreement. BACKGROUND/DISCUSSION The Irvine Ranch Water District (IRWD) is proceeding with the implementation of the Wells 21 and 22 Desalter Project, which consists of: pumps and wellhead discharge facilities at Wells 21 and 22; an untreated water pipeline to deliver water from the wellheads to the treatment plant; a reverse osmosis treatment plant; a brine disposal pipeline from the groundwater treatment plant to a sewer system; and a finished water pipeline to deliver water from the treatment plant to the IRWD service distribution system. In 2009, IRWD received a federal grant of approximately $11 million toward design and construction.of these facilities for the beneficial use of this impaired groundwater. To remain in compliance with federal grant requirements, the majority of funds for this project must be obligated by September 30, 2011. To meet this schedule objective, it will require the aggressive implementation of all project components. The accelerated implementation will require the active cooperation of the City of Tustin, wherein the majority of facilities will be constructed. In an effort to establish a framework for that cooperation, staff has negotiated the terms of a Cooperative Tustin-IRWD Coop Agreement Wells 21 & 22 October 19, 2010 Page 2 Agreement with the IRWD staff. A copy of the draft terms and conditions for the Cooperative Agreement with IRWD is attached. The Cooperative Agreement between City of Tustin and IRWD will outline an adaptive management strategy for the Wells 21 and 22 Project. IRWD and the City will work with Orange County Water District (OCWD) to establish baseline operating conditions for the project, including historical IRWD pumping from the area. OCWD will then model the historic conditions and determine water levels assuming baseline production from City of Tustin's and IRWD's wells under various overdraft conditions. The modeling will incorporate historic production from Wells 21 and 22 (formerly Frances Mutual Wells 17 and 18) in the baseline. The City of Tustin and IRWD will then develop mitigation measures with the help of an independent third-party consultant. The work of the consultant will be managed by OCWD staff in conjunction with the City of Tustin and IRWD. The consultant will review the modeling conducted by OCWD and determine the incremental impacts to Tustin's existing wells attributable to the Wells 21 and 22 Project. Based upon the impacts identified, the consultant will identify mitigation measures to address impacts to any affected City of Tustin wells. OCWD, the City of Tustin and IRWD propose to form a Joint Groundwater Engineering and Management Committee (Joint Committee) made up of representatives from each agency. The purpose of the Joint Committee is to facilitate communication between IRWD and the City of Tustin, and aid in the administration of the Cooperative Agreement. Staff from OCWD, namely the General Manager and Chief Hydrogeologist, were included in the process to develop the terms and conditions of the Cooperative Agreement with IRWD and has agreed to participate in the tasks described above. D~~~~. Stack, P.E. Die f Public Works/City Engineer Attachment (s): Draft Terms & Conditions for Cooperative Agreement, dated 9/7/2010 S:\City Council Items\2010 Council ItemsWuthorize IRWD cooperative agreement well 21 & 22.docx DRAFT City of Tustin -IRWD Terms and Conditions for the Cooperative Agreement Regarding the Wells 21 & 22 Groundwater Treatment Project September 7, 2010 The purpose of this Cooperative Agreement is to establish a methodology for quantifying and mitigating groundwater production and well operation impacts to the City of Tustin Water Service area associated with the Irvine Ranch Water District (IRWD) We1121 & 22 Groundwater Treatment Project in the City of Tustin. IRWD Wells 21 & 22 were constructed in 1992 on the sites of the former Francis Mutual Water Company (FMWC) Wells 17 & 18. Due to the cost of treatment for elevated nitrate and Total Dissolved Solids (TDS), Wells 21 & 22 were never put into production. Until the mid-1980s, the former FMWC operated Wells 17 & 18 and produced a combined maximum of approximately 2,400 acre-feet (AF) in water year 1975-76. Substantially less was produced in other years, until production ceased in 1985. IRWD acquired FMWC in the 1980s. Subsequently, in 2008 and 2009, IRWD rehabilitated and retested the production capacity and water quality of Wells 21 & 22. The groundwater produced by these wells was determined to be unsuitable for potable uses without treatment. In 2009, IRWD received a federal grant of approximately $11 million toward design and construction of a groundwater production, conveyance, and treatment facilities including Wells 21 & 22 for the beneficial use of this impaired groundwater. The total project cost is estimated at $48 million. With this project, IRWD will be able to provide domestic water production from these facilities to further improve reliability to IRWD customers. To remain in compliance with federal grant requirements, the majority of funds for this project must be obligated by September 30, 2011. Tustin has expressed concern regarding potential impacts to its domestic wells from the increased production attributable to the IRWD project. The concerns Tustin has expressed include existing and future well production capability and potential drawdown impacts, restrictions, and/or loss of groundwater production. The steps outlined below are intended to provide a framework for cooperation between Tustin and IRWD for quantification and mitigation of impacts associated with the Wells 21 & 22 project. Regardless, the IRWD project should be engineered with Tustin's on-going groundwater supply program to limit future impacts for IRWD wells situated within the Tustin's Water Services Boundary. The following terms provide the basis for a Cooperative Agreement between Tustin and IRWD to outline an adaptive management strategy for the Wells 21 & 22 Project: 1) Establish Baseline Operating Conditions: a) Tustin and IRWD will work together in consultation with Orange County Water District (OCWD) to determine a production and water level baseline condition for modeling purposes. This baseline will be developed based upon: 2010'09'07 Tustin-IRWD Cooperative Agmnt Final September 7, 2010 Tustin -IRWD Cooperative Agreement Regarding Wells 21 & 22 Page 2 i) Existing production by Tustin from existing wells within the Tustin service area ii) FMWC Wells 17 & 18 being actively produced at 1,500 AF; iii) Water levels in the area of Tustin's wells; and iv) Overdraft conditions in the basin as recommended by the OCWD, Chief Hydrogeologist. b) OCWD will model the existing conditions and determine water levels assuming baseline production from Tustin's wells under various overdraft conditions. 2) Analysis and Mitigation of Impacts Associated with IRWD's Wells 21 & 22 Treatment Plant Project: a) Using the baseline conditions established above, OCWD will model a "with project" condition that determines water levels in adjacent Tustin wells assuming a maximum annual production of 7,100 AF for Wells 21 & 22 as proposed for the Treatment Plant Project; b) Water level impacts for the "with project" condition will be determined under various overdraft conditions; c) Information will also be developed regarding other .factors affecting the capacity of Tustin's wells, including maintenance status and well capacity deterioration due to aging (corrosion, plugging, sanding, etc.);. d) IRWD will retain at its sole expense an independent third-party registered engineer and hydrogeologist (consultant) mutually acceptable to Tustin, IRWD, and OCWD that will conduct the analysis of project impacts and recommend mitigation measures. The consultant's scope of work will be attached to the Cooperative Agreement. The consultant will be managed and directed by OCWD staff in consultation with Tustin and IRWD. The consultant will: i) Review the modeling conducted by OCWD and other pertinent information; ii) Determine the impacts to Tustin's existing wells directly attributable to the Wells 21 & 22 Treatment Plant. Project based upon the "with project" condition, and will provide a written technical memorandum to Tustin, IRWD and OCWD; and e) Based upon the impacts identified and documented above, potential mitigation measures may include, but not be limited to, the following alternatives: i) Compensation for increased electrical costs associated with pumping using theoretical drawdown, power cost and plant efficiency; ii) Physical modifications to Tustin's wells, such as lowering pump bowls or other modifications to maintain the well(s) in service; iii) Financial participation by IRWD in Tustin well replacement projects to incorporate design features that increase production to offset the impacts of Wells 21 &22; September 7, 2010 Tustin -IRWD Cooperative Agreement Regarding Wells 21 & 22 Page 3 f) In the event that IRWD's operation of the Wells 21 & 22 project is determined to result in sustained impacts that result in a loss of water production capacity from Tustin's existing wells or groundwater treatment projects that are not cost effective to mitigate, IRWD will, in consultation with Tustin, provide an equivalent amount of water (replacement water) to Tustin from the Wells 21 & 22 project or other sources at a cost equivalent to Tustin's water production costs from the impacted facilities. i) IRWD shall be responsible for all costs to construct interconnection capacity between the IRWD and Tustin systems, as necessary, so that replacement water sources can be delivered to Tustin in a comparable pressure zone and at delivery point(s) mutually agreed to by IRWD and Tustin. 3) Option for Acquisition of Capacity in Wells 21 & 22 Groundwater Treatment Project: a) Separate and apart from the mitigation measures discussed above, IRWD will provide Tustin an option to purchase capacity on a pro-rata basis in the Wells 21 & 22 Groundwater Treatment Plant of up to 1,000 AF per year. i) Tustin would pay IRWD a proportional buy-in price for the additional capacity based on the total project cost of the well(s),. treatment facility, real property and conveyance facilities required to deliver the water o Tustin. ii) Tustin and IRWD would enter into an operating agreement to proportionately allocate all O&M and replacement costs for the acquired capacity. iii) Water delivered to Tustin from the project would be included in Tustin's Basin Production Percentage {BPP) calculation and would be subject to the execution of an amended BEA exemption agreement with OCWD. 4) Joint Management and Review Committee a) OGWD, Tustin and IRWD shall form a Joint Groundwater Engineering and Management Committee (Joint Committee), and shall each appoint one representative and one alternate representative to the Joint Committee. The primary purpose of the Joint Committee shall be to facilitate communication between the parties and aid in the administration of this Agreement. Tustin and IRWD shall give full consideration to all recommendations of the Joint Committee. The Joint Committee shall meet periodically, but at least once a year, to perform such tasks as may be assigned to it by the parties from time to time, including, but not limited to, the following: i.) Update the quantification of impacts from the Well 21 & 22 project and other local groundwater production changes; ii.) Review the effect of mitigation measures on the existing Tustin wells; iii.) Suggest additional or improved mitigation measures, if necessary; iv.) Engage third party experts to assist in additional analysis of project impacts and the development of mitigation measures; September 7, 2010 Tustin -IRWD Cooperative Agreement Regarding Wells 21 & 22 Page 4 v.) Resolve disagreements between Tustin and IRWD regarding the implementation of this Agreement; and vi.) Perform such other tasks as may be assigned by Tustin and IRWD.