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HomeMy WebLinkAboutTAC Minutes 11.18.20 Technical Advisory Committee (TAC) Meeting 1:00 P.M. – Wednesday, September 9th, 2020 Mendocino County Administration Center, 501 Low Gap Road, Room 1010, Ukiah CA 95482 Virtual Meeting via Zoom Supporting Documents: November 11, 2020 Agenda UVBGSA TAC Presentation September 9, 2020 Agenda 2021 UVBGSA TAC Calendar Meeting Summary Call to Order – Roll Call TAC Members Present: Glenn McGourty, Beth Salomone, Laurel Marcus, Don Seymour, Stephen Maples, Devon Jones, Deborah Edelman, Mike Webster, Absent: Ken Todd, Levi Paulin Sonny Elliott Jr. All Others Present: Sarah Dukett, Laura Foglia, Amir Mani, Samira Ismaili, Andrew Bake Approval of Meeting Summary from the September 9, 2020 Meeting Committee Action: Motion by Don Seymour, Seconded by Beth Salomone. Motion Carries to approve meeting summary from September 9, 2020 Approval of 2021 UVBGSA TAC Calendar Committee Action: Motion by Beth Salomone, Seconded by Michael Webster. Motion Carries to approve 2021 UVBGSA TAC Calendar Discussion Regarding Updates to the Monitoring Network and Data Requests Presenter/s: Laura Foglia, Larry Walker and Associates Introduction: Will cover as much as possible but plan to have a SW working group meeting in December 3 to 4 TSS Wells are waiting to be submitted and instrumented to DWR 4 Instrumented wells in Southern Ukiah. 4/5 Wells to be drilled in Northern Ukiah. Discussion: None Committee Action: None Discussion Regarding the Development of Future Scenarios Presenter/s: Laura Foglia, Larry Walker and Associates, Amir Mani, Larry Walker and Associates Introduction: Scenarios based on Future Scenarios Survey Sent out. Board Direction: Choose High Impact Water System Scenarios with direct management actions and focus on scenarios that will be approved by DWR. Future Scenario: Climate Change Transient Method would be more appropriate to Lake Mendocino due to seasonality. Drier seasonality would impact recharge. Future Scenarios: PVP Removal of Dam, No additional Flows (Worst-Case) No Change in Discharge Run of the River Scenario Project Management Actions Related to Future Scenarios Land Use and Ag Scenario – Not Helpful, No Major Change Recharge Projects - Would roll out in small steps Recycle Water – Helpful Scenario, City of Ukiah already rolling it out Urban Expansion, Pop Growth – No agreement on historical representative trends, combine with PVP, land conversion, and climate change Discussion: Climate Change Discussions on Baseline Don: Have to note the variability due to the seasonality of our basin. Beth: Surprised that 50 year baseline is being used instead of recognizing the variability in the past 25 years. Deborah Edelman, Glen McGourty, Devon Jones: Seconded Don Seymour: Marcus Trotta would know, can be brought on for Jan Meeting Committee Action: None Discussion and Possible Action Regarding the Initial Design of Monitoring Networks for Chronic Lowering of Groundwater Levels Presenter/s: Laura Foglia, Larry Walker and Associates, Amir Mani, Larry Walker and Associates Introduction: One Principal Aquifer system proposed by separate Aquifer units There is little aquifer separation, no clay lenses etc. so we are treating all three aquifers as one principal system. Ideally we would treat the system as two larger aquifers: Aquifer 1 and Aquifer 2 & 3 combined into one larger system. Conservative Decision is that we need 1 well per 25 sq. miles. Ideally we would have access to all of the CASGEM wells but DWR necessitates for inclusion into SGMA we need WCR/Drillers Log Equivalent as well as Construction Information. That limits the ability for our Monitoring Network Aquifer 1 Will have good basin coverage thanks to 3 mile overlapping radius of wells. Aquifer 1 has long term data gaps and GW Level SMC is tied to SMC Depletion Aquifer 2 data gaps in well completion reports. With instrumented wells we will have a good coverage for 3 mile radius with wells to spare. Aquifer 2 and Aquifer 3 will likely be combined as there is little separation. Aquifer 3 will have significant data gaps and relies heavily on nested wells. Discussion: Model Visualization Stephen: Will this change model visualization? Laura: Will not change it and will be labeling them as aquifer systems. Anyways with only four wells, it is hard to ideally model more than 1 aquifer. Without permeable layers we can treat all three aquifers as one system. Beth & Laurel: Plan sounds like a good update. Don: Have to note the variability due to the seasonality of our basin. Beth: Surprised that 50 year baseline is being used instead of recognizing the variability in the past 25 years. Deborah Edelman, Glen McGourty, Devon Jones: Seconded Don Seymour: Marcus Trotta would know, can be brought on for Jan Meeting Deborah: UV-7 is in question Devon: If we are unsuccessful with finding additional dataset will we be drilling more wells? Amir: We are instrumenting several wells as well as a treatment plant well as well as a USGS monitor. We are trying to fill this gap. Committee Action: None Discussion Regarding Initial Sustainable Management Criteria Development for Chronic Groundwater Level Decline Presenter/s: Laura Foglia, Larry Walker and Associates, Amir Mani, Larry Walker and Associates Introduction: Strong seasonality to the Basin but is not suffering from long term decline. Operational flexibility is a key criteria to the management of the Basin as well as setting the standards for each aquifer. Undesireable Result: Lack of availability of GW for Domestic, Ag or Industrial Users Spatial: 33% of RMP’s 2 or more wells exceed minimum thresholds for two consecutive years. Temporal: Average of the two lowest consecutive spring level measurements Redwood Valley Well – Aquifer II Only one year is below MT as this location Central Ukiah Valley – Aquifer II The Groundwater Elevation level changes across the basin Measurable Threshold 23 ft-bgs Two years in historical record is below MT Measurable Objective 20 ft-bgs Most helpful to LWA would be alternative methods suggested Discussion: Groundwater Level Map Tool Stephen: Think this is a valuable tool to pair with the SMC’s especially SW Depletion to inform choices Groundwater Level MO/MT Laurel: How does longer droughts affect these MO/MT? Setting a future standard is critical to evaluate management criteria Action Items and Closing Comments Committee Action: Committee asked to consider alternative MO and MT measurement methods and bring suggestions to SMC working group meeting in December. Public Comments on Items Not on the Agenda This time is reserved for the public to address the Committee about matters not on the agenda and within the jurisdiction of the Advisory Committee. Persons wishing to speak on specific agenda items should do so at the time specified for those items. Adjournment Beth Salomone moves to adjourn, Seconded by Laurel Marcus Meeting Adjourned at 3:04 PM