HomeMy WebLinkAbout2_10_21 TAC Minutes Summary_31021UKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY
340 Lake Mendocino Dr. Ukiah California 95482 (707)463-4363 fax (707)463-5474
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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
1. 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
2. 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
3. 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
o Reduce Evaporation Losses in Storage Facilities
Water Savr, Balls in Ag ponds
o 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
o 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:
UKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY
501 Low Gap Rd., Rm. 1010 Ukiah California 95482 (707)463-4441 fax (707)463-7237
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o Recharge Projects
Flooding Agricultural Fields
o 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
4. 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
o Map GDE’s
o Characterize hydrologic conditions of GDE’s
o Define Criteria for other sustainability indicators and the effect this has on GDE’s
o 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
UKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY
501 Low Gap Rd., Rm. 1010 Ukiah California 95482 (707)463-4441 fax (707)463-7237
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Created a Disconnected v Likely Connected analysis based on a depth to water of 30 feet
Next steps:
o 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
o Need to better understand which tributaries are gaining versus losing
We will use the data driven approach to better understand ISW
o If hydraulic gradients are managed to remain at 2015 levels or improvement, ISW
depletion will not worsen.
o This is why monitoring network is so critical to develop our groundwater
threshold because currently, the GW level is not enough.
o 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.
o James Linderman: Protect Spawning habitats for Migratory Fish
o 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
o Amir Mani: This ties into ISW work, if they run dry we are not meeting the SMC.
o 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.
o Laura Foglia: Need to look at all the beneficial users and uses in the valley
o Laura Foglia: These GDE’s need to be developed with adjusted depth to
groundwater
o James Linderman: This DEM will need to be adjusted based on Nature
Conservancy flow guidelines
o Laura Foglia: The Nature Conservancy guidelines are quite a high threshold,
other GSP’s have a 15 ft GW threshold for instance
o Amir Mani: These DEM’s will be refined to develop
o 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.
o 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
o Laura Foglia: Can TAC identify year/months they don’t want to see again
qualitatively and then we can apply data to that information
UKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY
501 Low Gap Rd., Rm. 1010 Ukiah California 95482 (707)463-4441 fax (707)463-7237
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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.
o James Linderman: 2015 was a terrible year because of the curtailment by the
water board
o 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.
o 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.
o 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
5. Discussion Regarding the Groundwater Elevation and Water Quality Monitoring
Networks
To be discussed at the March 10th TAC Meeting
6. Discussion Regarding Water Budget
To be discussed at the March 10th TAC Meeting
7. Action Items and Closing Comments
UKIAH VALLEY BASIN GROUNDWATER SUSTAINABILITY AGENCY
501 Low Gap Rd., Rm. 1010 Ukiah California 95482 (707)463-4441 fax (707)463-7237
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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
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.
9. Adjournment
Meeting was adjourned at 3:01 PM