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HomeMy WebLinkAbout2_10_21 TAC Minutes Summary Final Technical Advisory Committee (TAC) Meeting 1:00 P.M. – Wednesday, February 10, 2021 Mendocino County Administration Center, 501 Low Gap Road, Room 1010, Ukiah CA 95482 Virtual Meeting via Zoom Supporting Documents: February 10, 2021 Agenda UVBGSA TAC Presentation January 13, 2021 Minutes Summary Meeting Summary Call to Order and Roll Call TAC Members Present: Elizabeth Salomone, Laurel Marcus, Zachary Robinson, Sean White, James Linderman, Don Seymour Absent: Mike Webster, Levi Paulin, Ken Todd All Others Present: Amber Fisette, Laura Foglia, Amir Mani, Samira Ismaili, Andrew Bake, Don Seymour, Stephen Maples, Zachary Robinson Approval of Meeting Summary from the January 13, 2021 Meeting Committee Action: Motion forwarded by Beth Salomone and carried to review minutes and meeting summary from January 13, 2021 to the March TAC Meeting Discussion Regarding Projects and Management Actions Presenter(s): Laura Foglia, Amir Mani, Larry Walker and Associates Introduction: Model is running, we are in a position to begin running PMA Scenarios Project and Management Action overview – utilizing the templates Projects Reduce Evaporation Losses in Storage Facilities Water Savr, Balls in Ag ponds Implement Recharge Projects Using Ag fields to recharge utilizing frost protection systems and timely diversions Implementing multi-benefit infiltration project – Storm water BMP’s/LID’s Protect Source Water and Recharge areas through clamps on urbanization Several Management Actions were also proposed by Board Members, TAC Members and members of the public, they include: Recharge Projects Flooding Agricultural Fields Pumping Management Voluntary reductions of pumping by water right holders Discussion: Sean White: Geology of UVB limits regulated pumping Amir Mani: Utilize model to entirely restrict municipal pumping and Ag pumping Stephen Maples: Especially with the streams down by Hopland you will be able to see the increase/decrease in flows Laurel Marcus: When you discuss restricting development, what do you propose to see done especially with the exodus of people leaving the Bay Area for places like in the model. James Linderman: County has extensive LID manual for developments greater than 5000 feet. New housing developments will not provide a significant amount of growth in groundwater demand for the basin. Laurel Marcus: What is the LID systems based on? Infiltration or detention ponds. James Linderman: The system is designed for a 24 hour and 2 year event. Some systems do infiltrate and others route straight to the storm water system. Infiltration systems are being removed from LID protocols and instead the systems will be recharge oriented and anything in excess of those storms will be routed to storm water ditches. Laurel: We will need rough numbers of how much more each well will be pumping with demand increases. Committee Action: None Discussion Regarding Updates to Interconnected Surface Water and Groundwater Dependent Ecosystems Analyses Presenter(s): Laura Foglia, Larry Walker and Associates Introduction: Decide how we want to move forward on ISW and GDE Need to focus on what the GSA can reasonably manage with regards to Surface Water Depletion Streamflow Depletion results low flows, streambank incision and damage to ecosystems What Undesirable Results do the GSA want to avoid for ISW and GDE’s GDE Summary Map GDE’s Characterize hydrologic conditions of GDE’s Define Criteria for other sustainability indicators and the effect this has on GDE’s Discuss impacts on GDE/ISW with relation to other SMC and MT’s Undesirable Results for GDE’s, if the groundwater level drops then we are looking to develop our Management actions. Depth to Groundwater is an important criteria in the GDE analysis, using grid based analysis and compared this to rooting zone depth based on available information Created a Disconnected v Likely Connected analysis based on a depth to water of 30 feet Next steps: Temporal baselines, Reasonable conditions and assess impacts on GDE’s with other SMC’s with other reasonable conditions. Russian River Profile shows that the majority of the River is connected throughout the basin with some gaining and losing sections Need to better understand which tributaries are gaining versus losing We will use the data driven approach to better understand ISW If hydraulic gradients are managed to remain at 2015 levels or improvement, ISW depletion will not worsen. This is why monitoring network is so critical to develop our groundwater threshold because currently, the GW level is not enough. We need to decide on what is an undesirable result for these ISW and GDE Discussion: Laurel Foglia: What Undesirable Results are we looking to protect and what flows are we looking for. James Linderman: Protect Spawning habitats for Migratory Fish Laurel Marcus: Are we looking for areas outside of the alluvial basin because if we are looking at tributaries that run dry are they spawning habitats Amir Mani: This ties into ISW work, if they run dry we are not meeting the SMC. Don Seymour: Surface Water depletion ties into GDE’s but also ties into water rights and if you have SW depletion, those with water rights on the valley floor are also losing water. Laura Foglia: Need to look at all the beneficial users and uses in the valley Laura Foglia: These GDE’s need to be developed with adjusted depth to groundwater James Linderman: This DEM will need to be adjusted based on Nature Conservancy flow guidelines Laura Foglia: The Nature Conservancy guidelines are quite a high threshold, other GSP’s have a 15 ft GW threshold for instance Amir Mani: These DEM’s will be refined to develop Laura Foglia: The area may need to extend the river channel to absorb beyond the river banks as the GDE’s expand across the river. Sparse data will be used to develop this map to create 3 ISW representations. When the river is Gaining, Losing Connected and Losing Disconnected First step will be using TAC member knowledge next will be refining further using the model The Losing Disconnected SW Analysis needs to be refined to better understand the disconnection. Among GSP’s there is discussion what that threshold should be. Stephen Maples: Identify where Surface Water Depletion is “bad” In dry years how much is the groundwater depletion the lack of recharge because there has been no rain versus excessive groundwater pumping Laura Foglia: Can TAC identify year/months they don’t want to see again qualitatively and then we can apply data to that information When there is a wet year we need to implement few management actions because there are few management actions we need to take The minimum threshold in dry years can be a combination of surface water depletion and groundwater level drops in the monitoring network Have to demonstrate there is a correlation of groundwater level drops and pumping and surface water depletion. Because we have so little data we need to treat the SMC’s as adaptive In dry years the management actions cannot be undertaken because of the lack of water for everybody 2014/2015 is the critical year In a dry year, what is a possible action that can be taken to prevent water loss. We need to take consideration into the years where we have a 5 year drought and we need to be convincing that we can go lower than the MT for one or two years given the fact that the UVB will bounce back in a wet year. We need to be aware that without the PVP there will be a different level of bounce back. In terms of area specificity, we can get granular to 400 meter squares to see the impact of specific area wells for river recharge. James Linderman: 2015 was a terrible year because of the curtailment by the water board Devon Jones: In a year with a curtailment scenario it will force alternative sources such as groundwater pumping. With the TUCP, surface water curtailments, this will likely drive increased pumping during the curtailment period if they are not able to use their surface water. What are the variable levels within the watershed to set different criteria for different basin areas. Is the model specific enough that we can view specific wells to argue against curtailments for specific area. Zach Robinson: As we live in a drought prone area, we should think about pushing the limits further into the Red as 2014/2015 is a bad year but things will likely get worse than that. Don Seymour: While there is a fluctuation in the groundwater level currently, if there is less surface water because of the loss of the Potter Valley Project, we need to better understand the overdraft. Committee Action: None Discussion Regarding the Groundwater Elevation and Water Quality Monitoring Networks To be discussed at the March 10th TAC Meeting Discussion Regarding Water Budget To be discussed at the March 10th TAC Meeting Action Items and Closing Comments Closing Comments: Devon Jones: One Page List of Updated To-Do list for priority of reviewing materials as well as a timeline for rollout of Chapters. Action Items: LWA to draft Priority List of Topics and Timeline for Chapter Rollouts 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 Meeting was adjourned at 3:01 PM