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HomeMy WebLinkAboutMinutes Water Resources Advisory Committee - 02/25/2005 WATER RESOURCES ADVISORY COMMITTEE Minutes of February 25, 2005 Members present: Carola Serrato - Chair, Lena Coleman, Capt. Paula Hinger, Herman R. Johnson, Bob Kent, Jon Kiggans, Dr. Karen Rue, Dr. Jane Stanford, and Kimberly Stockseth. Members absent: Staff Present: Ron Massey, Assistant City Manager Danny Ybarra, P.E. Assistant Water Director Max Castaneda, Water Resources Management Advisor Yolanda R. Marruffo, Public Relations and Marketing Coordinator M. P. Sudhakaran, PhD, Water Laboratory Director Mrs. Serrato requested a motion to approve the minutes as presented. A motion was made by Lena Coleman and seconded by Dr. Stanford. The minutes of December 16, 2004 were.approved as presented. Mr. Massey provided a presentation on water management strategies on aquifer storage and recovery and modification of the reservoir operating policy, Lake Corpus Christi and Choke Canyon Reservoir pipeline and off-channel reservoir alternatives. He stated that the PowerPoint presentation was presented to the Regional Water Planning Group by HDR Engineering. Mrs. Serrato stated that although Mr. Massey was not at the RWPG meeting when the presentation was given, he was familiar with the information. She further stated that after seeing some of the issues discussed by the RWPG, that the committee could also provide their comments. Mr. Massey stated that the four items were being considered for inclusion to the Regional Water Plan. Some of the items were previously included in the Plan while others were variations of previous recommendations. The City currently has most of the items at various stages. The idea of using aquifer storage and recovery (ASR) is to take advantage of excess water flows during periods of heavy rainfall to allow the City to treat the water and save it for drier periods. The 2000 Regional Water Plan did not identify the use of ASR. The City uses a NUBAY model that simulates different operational procedures. The stream flows, rain and freshwater requirements to bays and estuaries are utilized to determine efficient use of ASR. Mr. Massey stated that ASR is underground water storage. Mrs. Serrato stated that she understood that water treatment operations would be increased to allow the water to be stored. Mr. Massey stated that as long as water goes down stream, channel losses would occur as opposed to transferring the water through a pipeline to increase the reservoir yield. The City would ultimately weigh the benefits and cost of installing a pipeline or utilizing channel transfers. Mr. Massey stated that similar options were being considered for the water from Garwood Irrigation Company. One of the options is to take the Garwood water out of the Colorado River and transfer it through a creek and catch it at Lake Texana where it wouldbe pumped through the Mary Rhodes Pipeline. He estimated that this option SCANNE D would cost approximately$5 million. Another alternative would be to build a pipeline to move the water from the Colorado River to Lake Texana which could cost$60 to $80 million. He stated that the benefit in spending the additional money was relative to the loss of water when it is placed in the creek. Mr. Johnson asked if the water injected into the ASR would remain cool or hot. Mr. Massey stated that the water temperature would increase and decrease based on the ambient temperature of the ground elevation. He stated that the City would look at other sites closer to the Lon Hill Plant. Based on previous experience on Padre Island, the City will perform additional studies. Mr. Massey stated that the City is considering injecting 500 million gallons of water using ASR. Mrs. Serrato asked if the City was looking into creating an underground conservation district. Mr. Massey stated that the City would look into creating an aquifer storage and recovery district as there was not interest to establish a ground water district which has taxing authority and could result in negative public opinion. Mrs. Serrato stated that her concern would be with regards to safeguarding water quality and cited the examples of numerous oil and gas wells that were not properly plugged. Mr. Massey agreed in that there are many considerations such as the migration of water within an aquifer from one direction to another with the possibility of collecting contaminants. The City prefers to locate in an area with still waters. The water will maintain separation and it may be best to be in a salt water area as it is less likely that anyone will tap into it. He stated that the City would stop short of pulling all the water out from the ASR. He stated that operating procedures would be established inclusive of safe parameters. He estimated that the cost would be less than $10 million. The City would investigate the opportunity to develop additional water supplies which are funded by part of the raw water charge. The process insures system reliability and safety factors. Mrs. Serrato asked if the ASR would produce 500 million gallons or 1,550 acre feet of water and if so, would the cost be examined under the City's proposed rate study. Mr. Massey stated that the City was presently negotiating a contract with a consultant to review the City's current rate structure and that the consultant would be asked to look at the methodology of allocating ASR cost. Mr. Massey stated that the consultant would look to allocate the cost to the various customer classes. He stated that the Padre Island Desalination study looked at thirty different combinations of pipeline and ASR and that the City is pursuing the most cost effective approach which is a combination of ASR and desalination as well as an elevated storage tank. He stated that Padre Island is flatland which limits the number of tanks. Mr. Massey stated that other items that have not been discussed such as the initial study would be funded by the federal government through the Corp of Engineers study. While the City will participate, the City will pay 50 percent share with the federal government paying the remaining 50 percent. He stated that the federal government will pay up to 60 percent of the construction cost. If the City does not qualify for federal funds and the project remains feasible, the City would have the option to pursue it through a phased approach and/or consider adding a partner that would bring money during a later phase of the project. He stated that the City would look at growth projections and evaluate that portion of the project. 2 . Mr. Massey made reference to the Reservoir Operating Plan that was last amended in the mid 1990s. The NUBAY model has certain parameters to release 33 cfs from Choke Canyon for stream flow purposes and to meet permit requirements held by the City of Three Rivers. Phase one is when Lake Corpus Christi is at full capacity with no ability to catch extra storage. Lake Corpus Christi is allowed to drop to 74 feet in elevation before water is released from Choke Canyon above the normal 33 cfs. Mrs. Serrato stated that in fairness to the people who live around Lake Corpus Christi, it is important to point out that they feel this is an item of contention. Mr. Massey stated that there are no private landowners around the parameter of Choke Canyon Reservoir which was a lesson learned from Lake Corpus Christi. He stated that the Reservoir Operating Plan is used to manage the Choke Canyon / Lake Corpus Christi reservoir system which allows the City to determine reservoir yield. The reservoir yield changes based on historical rainfall. He stated that rainfall total from 1997 to 2003 were being entered into the model. Mr. Massey stated that the purpose of the update was to integrate water supply from Lake Texana. The study will determine whether any changes need to be made in the Reservoir Operating Plan. He made reference to the map shown on the PowerPoint presentation depicting a pipeline from Choke Canyon to Lake Corpus Christi which could be developed to reduce channel losses. This project is also part of the feasibility study which was identified in the Regional Water Plan. Mr. Massey stated that it was a valid concept. Mrs. Serrato stated that one of the items brought up at the Regional Water Planning Group was the elimination of channel losses. She mentioned that possible water losses could occur to the aquifer that supplies nearby communities if a pipeline was built from Choke Canyon Reservoir to Lake Corpus Christi. She further stated that the pipeline could produce an additional 39,000 acre feet of water. Mr. Massey stated that was more water than purchased from Garwood Irrigation Company. He stated that some of the strategies for developing alternate water supplies are imaginative while others can be refined and become worthy to implement. Mrs. Serrato stated that the Corp of Engineers could get involved in this project. Mr. Massey made reference to the 2002 heavy rainfall when 1.8 million acre feet of water were spilled to the bays and estuaries. He stated that these alternatives were important to the City. Mr. Massey made reference to the Governor's Desalination Study which projected that the cost of water would be much higher, but still reasonable. More importantly, the City has a sufficient amount of supply for years to come. He stated that when neighboring communities reach the end of their supply, their cost may significantly increase from existing cost. Mr. Massey concluded in saying that the City had purchased its water supply through the year 2060 with the exception of some capital costs. Annual Water Quality Report Mrs. Marruffo discussed the content of the annual water quality report. She made reference to the hand out identifying the contaminants detected for 2004, based on water samples collected at the water treatment plant and at various point locations within the distribution system. Dr. Sudhakaran stated that the Texas Commission on Environmental Quality collected water samples and tests for various parameters and frequencies. He stated that some 3 ( of the metals and minerals are tested once a year. If the contaminants are detected, the City is required to report the findings. Some samples are collected quarterly such as trihalomethanes and disinfection by-products. Samples are collected at various locations such as at the water treatment plant, within the distribution system, and at the farthest point. He explained that the trihalomethanes was approximately 50 percent of the allowable limit such as the maximum contaminant level (MCL) for trihalomethanes that measured at 80 parts per billion (ppb)with the City sample measuring at 37 ppb. The water samples are collected by the residents where a City laboratory representative picks up the sample to submit to the State for testing. Mr. Massey clarified that water samples were collected from three different locations, such as the water sample collected at the water treatment plant, from residential customers or from the Water Department offices. Dr. Sudhakaran stated that samples are collected monthly from the Water Department building to test for iron, manganese, lead, copper, etc. He reported that the contaminants were less than 0.005 ppm. The results are available on the web site. The risk from lead and copper is primarily from possible leaching that may occur within the interior household plumbing pipes. Mr. Massey stated that residents are encouraged to flush water lines. Mr..Serrato stated that when testing was initiated for lead and copper, a survey was distributed to be able to identify the homes that would produce the worst case scenario. Mr. Massey stated that USEPA involvement began in the early 1990's. He stated that the risk is not to the system itself, but to the individual dwelling. Mr. Massey stated that turbidity readings created a challenge when excessive rainfall occurred and stirred up river water. Dr. Stanford stated that some of the constituents showed no maximum contaminant level (MCL). Dr. Sudhakaran stated that USEPA does not have MCL or MCLGs for all contaminants. Mr. Kent questioned the values for the parameters shown for the secondary drinking water standards. He stated that the values in some cases were twice as high as compared to the 2003 figures. He stated that hardness increased by 50 percent and asked if the City's water quality had deteriorated over the past year. Dr. Sudhakaran stated that the results were based on one water sample collected. Mrs. Serrato stated that the City had been looking at two areas, including the upper reaches of the Choke Canyon where salt concentrations and near the Calallen pool area where they are conducting an investigation. Mr. Kent stated that he was not sure whether 126 ppm in chloride is worst than 36 ppm, but the number is much higher. Mr. Massey stated that it goes to show the danger in collecting one sample due to the variability that may occur. Dr. Sudhakaran stated that the Water Department conducts its own sample which is posted to the web site. Mr. Massey asked if we can be more informative to the public with regards to showing more information. Dr. Stanford stated that the City could post the monthly figures in the annual water quality report. Mrs. Serrato stated that the TCEQ is very particular about what information is posted to the annual drinking water report. Mr. Massey stated that the information should be reported in a more meaningful way. A motion was made and approved by the Committee to post the results of the City annual average for secondary constituents. Mr. Johnson asked if there is anyway that residential customers can circumvent the cost of having a water well tested. He stated that a comprehensive water well test would cost approximately$1,000. Mr. Massey stated that it shows the disparity of individuals who 4 chose to develop private water well. The consumer has to make the investment to insure that their drinking water is safe as well as to the health officials. He commented on the fact that there is an expense in choosing private water sources other than municipal water supply. Mr. Massey stated that the City does not get into testing samples from water wells. New business Dr. Stanford requested that the City obtain a copy of the video relating to Texas water issues as shown on PBS. Mrs. Marruffo stated that she would be able to acquire a copy of the video. Mrs. Marruffo reported that four committee positions were up for reappointment. As a reminder, committee members should submit a letter to the City Secretary's office indicating their interested to serve another term. The next meeting was set on April 21, 2005. If no further business, the meeting was adjourned at 1:20 p.m. 5