HomeMy WebLinkAbout1_13_21 TAC Minutes Summary Final
Technical Advisory Committee (TAC) Meeting
1:00 P.M. – Wednesday, January 13, 2021
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
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 Todd, 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
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
Discussion Regarding Updates to the Integrated Model
Presenter/s: Amir Mani, Larry Walker and Associates
Introduction: Integrated Modeling Updates
Parts that can be tweaked but Model is finalized
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.
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
Tributary gaged flows
Accurate even with low flows. Limited discrepancies
Model can now be used for TAC discussion especially with regards to the Water Budget
Discussion:
Redwood Valley Flows
Diversion data was just received and will help calibrate the low flows
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
Data Collection – Beth
Create a subcommittee meeting with data sharing made a priority. Especially for future data collection
Committee Action: None
Discussion Regarding Preliminary Water Budget
Discussion Regarding Interconnected Surface Water and Groundwater Dependent Ecosystems
Presenter/s: Jason Weiner, Larry Walker and Associates
Introduction: USGS Stream Gage Analysis
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.
SW Depletion Analysis Upstream
Winter Months: High Positive Balance
Summer Months Minimal Difference due to low diversion and seepage
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
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
SW Depletion Analysis – Confluence to Hopland
93% of daily negatives are within seepage rate values
SW Depletion Analysis – Hopland to Cloverdale
Magnitude of negative values can be explained by gaging errors/seepage
SW Depletion Analysis – Summary
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 greatest 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.
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
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:
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 system 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
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
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
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
GW and SW Modeling
Stephen: Likes data driven approach and thinks this data can provide a good check on the model.
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 large 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
Discussion Regarding Introduction to Projects and Management Action
Presenter/s: Laura Foglia, Larry Walker and Associates
Introduction: Project and Management Actions
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
Sample Projects
Typically are structural infrastructure projects
Stormwater Capture, Recycled Water
Categorized
Exisitng PMA’s
Proposed or planned PMA’s to reach sustainability
PMA’s to be evaluated in the future
Discussion:
Beth Salomone: Has been working with Deborah on storm water locations.
Laura Foglia: Wants to simply promote concepts and ideas
Laurel Marcus: What would be the point of creating these groundwater recharge projects if the basin is already very robust.
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.
Laurel Marcus: While these projects are useful, for example the frost irrigation ponds were built at a large cost but the state has not finished handing out water permits for filling
these ponds.
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.
Stephen Maples: Thinking about these PMA’s could be very in time with any changes to the Potter Valley Project.
Committee Action: None
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
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.
Adjournment
Meeting Adjourned at 3:28 PM