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HomeMy WebLinkAbout1_13_21 TAC Minutes Summary DraftUKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY 340 Lake Mendocino Dr.  Ukiah  California 95482  (707)463-4363  fax (707)463-5474 1 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: • January 13, 2021 Agenda • UVBGSA TAC Presentation  November 18, 2020 Minutes Summary Meeting Summary 1. Call to Order and Roll Call TAC Members Present: Elizabeth Salomone, Laurel Marcus, Devon Jones, Mike Webster, Levi Paulin, Zachary Robinson Absent: Sean White, Ken Dodd, Javier Silva, Sonny Elliott Jr. All Others Present: Amber Fisette, Laura Foglia, Amir Mani, Samira Ismaili, Andrew Bake, Jason Weiner, Alex Straessle, James Linderman, Deborah Edelman, Don Seymour, Stephen Maples 2. Approval of Meeting Summary from the November 18, 2020 Meeting Committee Action: Motion by Elizabeth Salomone, Seconded by Levi Paulin. Motion Carries to approve meeting summary from November 18, 2020 3. Discussion Regarding Updates to the Integrated Model Presenter/s: Amir Mani, Larry Walker and Associates Introduction: Integrated Modeling Updates o Parts that can be tweaked but Model is finalized o Calibration conducted for Well Head Sensitivity  Calibration shows that majority of streamflow head measurements and calibration are in line with line of best fit  Majority of error occurs in Redwood Valley where there is less data and geology is a bit more uncertain. o Streamflow Gage Calibration  Hopland and Talmage Gages have high flow levels so easier to simulate  West Fork Gage needs to be better simulated  Gage flow data is very close to simulated data  Discrepancies can occur when diversions are not reported accurately UKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY 501 Low Gap Rd., Rm. 1010  Ukiah  California 95482  (707)463-4441  fax (707)463-7237 2 o Tributary gaged flows  Accurate even with low flows. Limited discrepancies o Model can now be used for TAC discussion especially with regards to the Water Budget Discussion: o Redwood Valley Flows  Diversion data was just received and will help calibrate the low flows o Monthly Diversion Numbers  Groundwater levels are not well captured due to lack of data.  Ideally continuous data management will be able to link streamflow gages with continuous well monitoring o Data Collection – Beth  Create a subcommittee meeting with data sharing made a priority. Especially for future data collection Committee Action: None 4. Discussion Regarding Preliminary Water Budget 5. Discussion Regarding Interconnected Surface Water and Groundwater Dependent Ecosystems Presenter/s: Jason Weiner, Larry Walker and Associates Introduction: USGS Stream Gage Analysis o Using Stream Gages in Basin  Difference Method allowing to see a data driven approach to see daily average flow difference.  Positive Difference between gages would show contributions to the system between stream gages  Negative Difference would show evaporation, diversion etc. o SW Depletion Analysis Upstream  Winter Months: High Positive Balance  Summer Months Minimal Difference due to low diversion and seepage o SW Depletion Analysis – Confluence to Talmage  Most negative differences focused in summer months in a seepage system  Seepage provides about 70% of losses in the system o SW Depletion Analysis – Talmage to Hopland  Diversions account for 25-100% of losses in the system.  Much of the daily negatives are within the range of reasonable seepage values  System is behaving in a manner we would expect o SW Depletion Analysis – Confluence to Hopland  93% of daily negatives are within seepage rate values o SW Depletion Analysis – Hopland to Cloverdale  Magnitude of negative values can be explained by gaging errors /seepage o SW Depletion Analysis – Summary UKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY 501 Low Gap Rd., Rm. 1010  Ukiah  California 95482  (707)463-4441  fax (707)463-7237 3  Mass balance shows frequent surface water loss and diversions explain at least a portion of losses  Lossess are within range of seepage rates  Highest volume of losses are between Confluence and Talmage where greates t number of diversions also occurred but there is also a higher level of seepage rates in that area.  Look into in the model to see why the volume of water is largest in that area. Either geologic conditions or higher head pressure pushes water into the soil. o Groundwater Dependent Ecosystems for SW and GW Trends  Plotted GW month by month  Sparse data makes detailed analysis difficult  Resilient basin area – possible GW level resiliency due to seepage.  Highly correlated SW losses with GW level drops  Possible lag of GW response due to seepage can be construed with data but overall GW levels are still declining.  Integrated model can produce results on gain/loss of streams and provide checks on models o Mapped Potential GDE’s  Utilizing CDFW, Nature Conservancy and Vegetation Mapping Datasets creating Potential GDE Maps  TAC working group will provide the map with local knowledge and provide mapped Potential GDE’s for analysis  Much of the species within the GDE as currently mapped will only be able to access water within 5 and 15 feet underground.  Couple Mapped GDE’s with groundwater data  Gridded approach creating gw elevation tiles within the basin across a temporal perspective  Point based analysis: Create a zone of influence around well to measure rooting depths to vizualize if the GDE is utilizing groundwater  These approaches will allow a temporal view to evaluate if GDE’s are utilizing groundwater in different years and different GW elevations. Discussion: o Seepage rates at the Confluence to Talmage area  Beth Saolomone: Surprised at high levels of seepage in that area  Jason Weiner: High level heterogenous geology within the basin and increased head pressure located next to the Dam  Model will provide best understanding of syst em dynamics, this presentation was just an exploratory data effort  Amir Mani: Diversion data used was only data provided by RRFC not estimates of Ag diversions. There are also a lot of municipal diversions are in this region in question as well as large AG fields on the East side of the river o East Fork Gage  Mike Webster: Would like to improve collection data of East Fork Gage  Don Seymour: USGS was in charge of maintaining the gage until it was contracted by Army Corps and the accuracy of the gage is now in question due to UKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY 501 Low Gap Rd., Rm. 1010  Ukiah  California 95482  (707)463-4441  fax (707)463-7237 4 the new contractor. Conversation in installing new gage downstream to ensure there isn’t an over release of water  High turbidity of Lake Mendocino affects stream gage measurements o EvapoTransporation rates  Devon Jones: Evapotranspiration of riparian vegetation might be also construed with ET of plants in Ag fields  Laura Foglia: Lot of power in the data and incorporating it into the model will make the system more robust. The current missing data o GW and SW Modeling  Stephen: Likes data driven approach and thinks this data can provide a good check on the model. o Nature Conservancy MetaData Layer for GDE  Laurel Marcus: Nature Conservancy dataset shows areas that are not rich with water, especially with a satellite based approach  How will model take into account channeling incision of river during the spring floods.  Jason Weiner: Need TAC input to make evaluations on GDE’s  Channeling incision is being noted and there are discussions on how to manage that incision especially since it has such a larg e impact on riparian vegetation.  Sam Sandoval: Instream flows into the Russian, LWA can provide cross - sectional data. Among tributaries and main channel we can have multiple data groups.  Jason Weiner: Pressures on the riparian vegetation are highly specific to instream flows.  Devon Jones: What is a timing process for groundtruthing some of these GDE’s  Laurel: Preliminary polygons can be provided at February TAC meeting and then use TAC member experience to groundtruth and then take further actions once we come in agreement. Committee Action: None 6. Discussion Regarding Introduction to Projects and Management Action Presenter/s: Laura Foglia, Larry Walker and Associates Introduction: Project and Management Actions o PMA’s  These will help respond to changing Basin conditions  Each PMA must support achieving sustainability for one or more indicators  Must be included in the GSP now to be able to evaluate them long term o Sample Projects  Typically are structural infrastructure projects  Stormwater Capture, Recycled Water o Categorized  Exisitng PMA’s  Proposed or planned PMA’s to reach sustainability  PMA’s to be evaluated in the future UKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY 501 Low Gap Rd., Rm. 1010  Ukiah  California 95482  (707)463-4441  fax (707)463-7237 5 Discussion: o Beth Salomone: Has been working with Deborah on storm water locations. o Laura Foglia: Wants to simply promote concepts and ideas o Laurel Marcus: What would be the point of creating these groundwater recharge projects if the basin is already very robust. o Laura Foglia: Multi-benefit projects are very useful and even if we are not building groundwater recharge we are creating agricultural storage ponds for example. We can say that because of these projects there is less of a draw on groundwater. o Laurel Marcus: While these projects are useful, for example the frost irrigation ponds were built at a large cost but the state has not fin ished handing out water permits for filling these ponds. o Deborah Edelman: Water storage does not only have to be SW diversions. Instead we could have multiple rainwater storage sites that are lower cost and more effective. o Stephen Maples: Thinking about these PMA’s could be very in time with any changes to the Potter Valley Project. Committee Action: None 7. Action Items and Closing Comments Committee Action: TAC Chair Vote Elizaebth Salomone was nominated and unanimously accepted as TAC Chair Levi Paulin was renewed and unanimously accepted as TAC Vice-Chair 8. 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. No public comments were submitted. 9. Adjournment Meeting Adjourned at 3:28 PM