Planning Commission - Regular Meeting

Good morning. I would like to call to order the Wednesday, May 6, Planning Commission meeting. Madam Clerk, would you please do roll call?

Chair Brooks? Excuse me. Commissioner Brooks? Commissioner Dameron? Present. Commissioner Moran Williams?

Present.

And Chair Brinzel and Vice Chair Richmond are excused for today.

Thank you. At this time, I would like the Commission to elect a temporary chair for this meeting. So if we would like to proceed with a motion, a second, and a vote, that would be great.

Motion for Commissioner Dameron to be the chair today.

Second.

All in favor?

Aye.

Okay. Let the record show that was unanimously passed and we will reset to conduct the meeting.

All right. Thank you, everyone, and please join me in the Pledge of Allegiance. I pledge allegiance to the flag of The United States Of America and to the republic for which it stands, one nation under God, indivisible, with liberty and justice for all. We will now open up public comments and recommendations. The commission invites public comments and recommendations concerning current issues and future prospects of a planning nature, which are within the jurisdiction of the Planning Commission anyone who wishes to speak to the Commission on such a matter if it is not on the agenda may do so at this time Alright, looks like we have no one in the room and do we have anyone on the phone?

No public comment.

Okay, thank you. The clerk of the Commission requests approval of minutes from the regular meeting held on 04/01/2026. Is there a motion?

So moved.

There's been a motion. Is there a second? Second. All those in favor please say aye.

Aye.

Any opposed? Okay. Minutes are approved. And on to the agenda review. And Mr. Parker?

Good morning, Chair. Today, there are two items before the Commission. The first is item 7A, the Bremer family winery use permit major modification number P220086. This item in your packet you will find a request for continuance from the applicant which is supported by staff and there will be no presentation on this item but the request is to open the public hearing take any public comment and continue to a date certain of Wednesday July 1 And then the second item before you today is an administrative item, item 8A, which is to receive a presentation on the Napa County Public Draft 2026 Water Availability Analysis Guidance Document and Supplemental Technical Report.

Great, thank you. And we'll move to disclosures. Commissioner Moran Williams.

I have no disclosures at this time.

Thank you. And Commissioner Brooks.

I had phone conversations with legal representation for the applicant and scheduled a site visit cancelled when we found out that it will be moved forward when

we found out that there will be a continuance.

Thank you. And for item 7A, I met with some neighbors near the project.

And I also met with neighbors near the project and did a windshield tour of the neighborhood surrounding the property, but we didn't go onto the property.

Great. Thank you. Okay. So that brings us then to item 7a. John Bremer et al. Addressed Bremer Family Winery use permit major modification number P22-eighty6 mod, an exception to the Napa County Road and Street Standards. And so it sounds like Mr. Parker, you're going to take this item. Is that right?

That is correct.

All right.

So at this time, we would like the commission to officially open the public hearing, accept any public comment, and then continue the item to a date starting of July 1. There will be no staff or applicant presentation today.

Thank you. Okay, so we will open the public hearing for item 7A, and we will start then to see if there is any public comment on this item if there is please feel free to approach the podium state your name and you'll have three minutes Alright. No one in the room?

Anyone on the phone? No public comment.

Okay. Then we will close the public hearing, come back to the commission. And are there any comments? And if not, is there a motion?

I move that we continue this to a date certain of July 1.

Second.

Alright. There's been a motion and a second. All those in favor, please say aye.

Aye.

Any opposed? Okay. Item is continued to a date certain. And that brings us to our administrative item, AA, for the Napa County Public Draft 2026 Water Availability Analysis, guidance document and supplemental technical reports all right and once you're all settled whoever's taking this first it's all yours

Good morning Chair Dameron and Commissioners. I'm Patrick Ryan, Assistant Director of Planning, Building, Environmental Services, and I'm here with Vicki Kressinger, Senior Principal Hydrologist for Ludorff and Scalmanini Consulting Engineers. We are pleased to present information pertaining to the Napa County 2026 Water Availability Analysis Public Draft and Supporting Technical Report. Today's agenda, we're going to discuss the Napa County groundwater management and water availability analysis guidelines and some of the information that's provided in there. The public draft 2026 WAA procedures and screening process will go through a few examples for you to kind of outline how the process and how staff will be evaluating these projects.

And then we'll summarize the twenty twenty six updates and the next steps for the public draft process responding to comments and eventually taking this to the board of supervisors. The principles embodied in the water availability analysis have been a cornerstone of Napa County's groundwater management since 1991. Originally developed during the 1990 drought when concerns over increased groundwater demand and potential impacts on neighboring wells led to the creation of a simplified three phase analysis. The framework was later formalized and updated following adoption of the groundwater conservation ordinance, title 13.15 in Napa County code in 1999. And in 2015, the board of supervisors adopted the water availability analysis guidance document, which established procedures to assist staff, decision makers, applicants, neighbors, and other interested parties.

Its primary purpose remains to ensure the proposed groundwater use does not substantially reduce supply or interfere with recharge, thereby preventing long term deficits in local water systems. The 2026 water availability analysis applies to groundwater uses throughout an existing, improved, or new water supply system and increases or any increases in the intensity of groundwater extraction on parcels related to land use permitting. The water availability analysis will apply to both ministerial and discretionary projects using groundwater. The reason for this recent update is to provide updated data and processes to individuals such as staff, applicants, and their design professionals. It provides clarity in the process, consistency in applying the water conservation measures that are identified in the water availability analysis, as well as streamlining and increased efficiency in processing and providing staff these reports in these types of projects.

Permitting and management of groundwater and interconnected surface water is a is a primary concern in Napa County, specifically as it relates to the Napa Valley Sub Basin and some of the other areas identified in the WAA. The two documents I've I've referenced before were released for public comment on March 27, and that is a sixty day comment period that will end on May 26. These two documents can be found on the Napa County websites at Planning Building Environmental Services main page, or you can contact any member of Planning Building Environmental Services to get the information. We will be taking comments as I stated through May 26, and we encourage our stakeholders, our community members, our design professionals to review the document and provide their feedback. The 2026 updates to the WAA addresses critical groundwater and interconnected surface water management considerations that have emerged since the WAA was first written in 2015.

Some key updates include identification of four delineated groundwater areas with unique requirements. This includes the Napa Valley floor, the new Northeast Napa management area, the Millikan Sarco Tuluke groundwater deficient area, also known as the MST, and all other areas of of Napa County. For the tier one analysis, which is related to our groundwater use, updates it updates screening criteria for the Napa Valley sub basin in a streamline and it provides a streamline methodology for estimating recharge in areas outside of the of the Napa Valley sub basin. For the tier two analysis, which is related to well and spring interference, the updates in the 2026 WAA provides clarity clarified methodology for analyzing potential interference for those nearby wells and nearby springs. Our tier three analysis, which is related to our surface water interconnection and public trust resources consideration, provides protective standards for groundwater extraction within 1,500 feet of significant streams both inside and outside of the Napa River watershed.

I'm gonna pass it off to my colleague, Vicki, to for the next portion of this presentation.

Good morning, commissioners. I'm Vicky Krutzinger Graber with Ludorff and Scalmanini Consulting Engineers. And this part of the presentation provides a brief overview of the key water availability analysis components. So as an overview, as Patrick just mentioned, there are the county groundwater extraction areas that are key to all of the procedures and the process for the WAA. And the screening process, similar to the 2015 water availability analysis, has three tiers.

Tier one relating to water use criteria, tier two for well interference criterion, and tier three for groundwater surface water interaction and looking at potential streamflow depletion criteria. So historically, the water availability analysis had typically referred to the Napa Valley floor area of the county. Since the Napa Valley subbasin has specific groundwater sustainability plan requirements, the 2026 WAA clarifies the valley floor portion of the subbasin. The sustainable management criteria that form the backbone of the groundwater sustainability plan are the and are the quantitative metrics by which the sustainability of the Napa Valley sub basin is evaluated, including the sustainable yield, this distinction is important. So the Napa Valley Subbasin shown on the image on the right is the entirety of the dashed line delineating the subbasin boundary, As noticed by Patrick, there's a special area that I'm going to talk further about in slides ahead, this is the Northeast Napa Management Area.

It's a formerly designated management area within the sub basin. And now the Napa Valley floor, we're referring to the portion of the Napa Valley sub basin that excludes the overlapping Northeast Napa management area and the portion of the sub basin that extends into the Millikan Sarco Toluque area. The groundwater deficient areas, specifically the Millikan Sarco Toluque area as designated in the county's groundwater conservation ordinance, county code thirteen fifteen. This is also outside of the subbasin, but a key part of the WAA procedures. And then there's all other areas all locations outside of the Napa Valley Subbasin and outside the MST.

Here on this slide, we're zooming into the areas that I just described. We have the subbasin in the lower part of the slide area, the dash boundary, that finger of the subbasin that I mentioned that extends into the MST, the Northeast Napa Management Area with the horizontal hatching, and the MST itself, and then all other areas outside the subbasin and the MST. Importantly, the Napa Valley Sub Basin, which extends into the MST, the water use criteria for the MST applied to that area.

I'm confused by that area. It's called the Napa Valley Subbasin. Is that also a special area in the same way that the Northeast Napa is a special area?

The Napa Valley Subbasin is not a special area in and of itself. The management area, the Northeast Napa Management Area, is a specially designated area that is within the Napa Valley Subbasin. That finger is still part of the Napa Valley Subbasin, but it isn't included in the water use criteria in the same way. So, I'll be coming to slides.

Okay, this one goes right.

Yeah, I know it's rather confusing with all these different terminologies, but we are trying to clarify and I'll be talking about in a moment what used to occur as the Millikan Sarco Toluca area that overlapped into the designated Napa Valley Subbasin. Now it's being redelineated to be entirely separate from the Napa Valley Sub Basin. So I'll go over this again as we talk about how we've identified the water use criteria. So on the Northeast Napa management area, the California Code of Regulations and this came about with the Sustainable Groundwater Management Act that was adopted by the state in September 2014 and implemented in 01/01/2015. That code of regulations defines a management area as an area within a basin for which the Grower Sustainability Plan may identify different minimum thresholds, measurable objectives, monitoring or projects and management actions based on differences in water use sector, water source type, geology, aquifer characteristics, or other factors.

In 2017, the Napa County Board of Supervisors requested a study of the Northeast Napa Mana area to assess groundwater availability and the potential constraints on recharge. Based on the studies done at that time, the area was first designated in 2018 as a formal sub basin management area to better manage groundwater in a complex hydrogeologic setting unique from the rest of the sub basin. The Northeast Napa Management area is a formerly designated management area in the Groundwater Sustainability Plan, and the factors that characterize this area as unique from the rest of the sub basin are described in the Groundwater Sustainability Plan. And I'm going to touch on a few of these. And I just went through that slide.

This slide is showing some of the key features relating to the geologic setting of the Northeast NAPA Management Area. It illustrates the underlying geology, which is shown on this slide. There's a cross section going through the Northeast Napa Management Area and the south central portion of it from west to east, and then the actual cross section shown on the slide as well. In this area, there's a very thin veneer of alluvium that overlies more consolidated formation materials. And it's in these deeper, more consolidated deposits from which groundwater is produced.

That thin alluvium is pointing to on this slide, that thin yellow area near to the river. But as you move away from the river, then you are in more of the consolidated rock formation. Other key features that make this area unique and how it needs to be managed are two fault structures. There's the Soda Creek Fault located on the eastern boundary of the Northeast Napa Management Area and at the eastern boundary of the sub basin, adjacent to the MST, and then also the East Napa River Fault that parallels the Napa River in this area. Both of these faults constrain flow into the area.

Could it? Sure. On the, if you go back to that chart, the profiles you're showing there, are those test wells you've, are those from well logs where you're I assume that's characterizing the different material that you're going through?

Correct. These are all boring logs and wells constructed at these locations and utilized largely as part of the 2013 updated geologic characterization that was done throughout the county, but especially focused on the Napa Valley sub basin. And since that time, there have been a number 30 monitoring wells installed that have expanded the information, particularly in unconsolidated deposits within the sub basin, where monitoring wells have been installed to help the understanding of interconnected surface water and groundwater.

Thanks.

So on this slide, we wanted to highlight some of the groundwater conditions that are also unique to this area. There are trends that are not representative of what we see in overall sub basin conditions. Here, we highlight with two hydrographs, the locations of these wells are shown by the red circles on the the map. And these are what are referred to as groundwater sustainability plan representative monitoring sites where groundwater levels are tracked over time to look at trends and conditions. And then those measurements are related to sustainable management criteria, which are referred to as the measurable objectives, the levels at which we would like to achieve, and the minimum thresholds, the levels at which create a trigger, and potentially, if they remain below these levels, that they create an undesirable result.

In this area, we've seen seasonal fluctuations of groundwater level trends with higher levels occurring in the spring. However, the fall groundwater levels have been persistently below the minimum thresholds that I mentioned. The trends in this area mean that management actions are needed to improve groundwater conditions and to ensure the long term sustainability of groundwater resources within this area. So I'm going to turn now the next slide's highlight the WAA twenty twenty six procedures and screening process. The water use criteria are established according to the location of the applicant's parcel, and these include the four key areas the Napa Valley floor, the Northeast Napa Management Area, the Millikan Sarco Toluca area, and all other areas.

And for clarification, again, the sub basin was mentioned earlier as a key area that is regulated through the Department of Water Resources and the Sustainable Groundwater Management Act. Here, for the water use criteria, we're focusing on the Napa Valley floor as a water use criteria area, the Northeast Napa Management Area, the MST, and all other areas for the water use criteria. And I'll continue to talk more about what that means with respect to each of these areas. The groundwater use criteria are detailed in the WAA guidance document that is out for public review and comment. And this is complemented by a a companion document that includes the methods that were used to develop the criteria, and this is in a technical report.

The 2026 WA includes the streamlined process for estimating recharge for areas outside the Napa Valley subbasin, and I'll discuss this more in upcoming slides. This slide and the next slides focus on the methods used to determine the water use criteria. And with respect to the Napa Valley sub basin and the work that was done to estimate the sustainable yield for the sub basin, it's important understand that that is all of that process is documented in the very long, groundwater sustainability plan that was approved in January 2023 by the Department of Water Resources. It's also important to understand that the 15,000 acre feet per year estimate of sustainable yield is the only state approved sustainable yield for the sub basin. And that means that it was determined with the sustainable management criteria for six sustainability indicators that came about through the Groundwater Sustainability Plan regulations under the Sustainable Groundwater Management Act.

So, related to the sustainable So,

to this 15,000 acre feet per year that we've decided is a sustainable draw that we can have on the aquifer, at a macro level in terms of looking at the new guidelines, it looks like for the sub and previously in the analysis we needed to do relative to the WAA, we were at 0.3 acre feet per acre and now it looks like we've increased it to 0.5 acre feet per acre in the primary part of the sub basin and I was just trying to get a grip on that versus the fact that we're still asking people to do a 10% voluntary reduction. So we're allowing a 40% increase in what you can draw now if you're in that sub basin, but we're still asking everybody to decrease everything by 10. So I was just wondering what the rationale is for us deciding that we're going to come up from 0.3 acre feet to 0.5 acre feet for the sub basin.

So, a long question and I'll try and be brief with a response. Part of the next slides will explain a little bit more about that, but a very good question about the 10% reduction. So at this time, the 2026 WAA utilizes the quantified sustainable yield of the 15,000 acre feet per year for the entirety of the sub basin, and then I'm gonna describe about how we've looked at proportioning that to the specific areas that have water use criteria. We are, at this time, the county, the the Groundwater Sustainability Agency in particular, is encouraging that those groundwater users across the entirety of the sub basin and that includes all sectors of groundwater use, not just one sector, not just ag, but everybody that's using groundwater that they do their part to voluntarily reduce, you know, the amount of groundwater that they're using. So there is the the work done to try and relate the WAA to the sustainable yield, partly because the 10% can also be achieved not only by reducing pumping, but if there are intentional ways to augment or replenish the groundwater system through recharge operations or in other ways in order to achieve sustainability by 2042.

Those are also ways to maintain sustainability within the sub basin. And I'm not sure if that completely answered the question. There are several work plans that have been developed with GSP implementation. One of those is a document relating to water conservation methodologies and approaches. Another is the groundwater pumping reduction work plan.

And there are several things that are being implemented in response to the guidance put forth in that work plan, one of which is trying to coordinate with existing certification entities to encourage agricultural those in the wine industry, grape growing industry to participate and to provide data through the certification program in an anonymized way in order to help inform some of the other technical work that's occurring. There's also work being done to look at recharge opportunities within the sub basin. So there are many different things going on in parallel to try and look at both opportunities to reduce groundwater utilization through various means of water conservation and also to replenish groundwater through various means of replenishment, including alternative uses instead of using groundwater, potentially dry farming, potentially optimizing their practices for vineyard management, looking at recycled water opportunities as something that has been coordinated with the City of St. Helena, looking at potential recycled water use in that area.

I mean, it did answer part of the, but with all everything you've said, it seems like we're using all these methodologies to try and get a reduction. But now, it looks like we've allowed it to come up from 0.3 to 0.5 acre feet for new applicants and that seems to be in the opposite direction of encouraging people to use the least amount of water in their projects. And on the surface of it, seeing it go up like that, go, oh, we must be in control of it now and we're doing fine because we can give a bigger allocation to new projects now. But that doesn't seem like what's going on here. So was just trying to understand the rationale for why we want to increase it for a subset of the applications while we're still looking at all these other methodologies and putting some pressure on people to say, hey, voluntarily get your draw down.

Was the 0.3 acre feet applied to all zones in the 2015 version, or was it just the MST?

So the point three was an interim criterion Right. That occurred, following a meeting with the board of supervisors in June 2022 that described things that had come about at that time with the governor's executive order. And at that point in time, because of drought conditions and other factors besides for the governor's executive order, attention to public trust considerations and and many other things, that that point three was arrived at by looking at the entirety of the acreage in the sub basin and allocating that water use across all acreage. As I'm going to describe in the coming slides, then there's a finer look at the acreage in the sub basin, some of which is parklands and other lands. And so it was focused on to more of where the groundwater use is actually occurring or where could it occur in the future.

And that 0.5 came about through looking at a refined analysis of the land use current and in the future without considering all these other lands that don't involve the same amount of groundwater use. So in the next couple of slides, I'm going to describe that further. So some of the factors in looking at the sustainable yield, they included looking at the proportion of the Napa Valley sustainable yield that would apply to the designated management area. And in this case, that included a separate analysis of the Northeast NAPA management area to evaluate what the proportion of the sustainable yield specific to that area is. And that's described at length in the technical report.

We also looked at the current land use data, including the currently developed land and also land potentially to be developed in the future. And then also looking at current appropriate uses of groundwater, and this includes the city of St. Helena at its designated and I'll say, quote unquote, safe yield of three fifty acre feet per year. Safe yield does not equate to sustainable yield, but in this case, it is the city's own analysis to determine the amount of groundwater needed for conjunctive use with its surface water supplies. And we're looking at that as a portion of what is considered within the overall sub basin and the sustainable yield.

So as we look at all three of these parts relative to the 15,000 acre feet per year for the sustainable yield and proportion them, then the Napa Valley floor, and this is just that newly defined Napa Valley floor area, and for areas with overlying groundwater users, excluding the Northeast Napa management area and the portion of the sub basin extending to the MST and minus the appropriative use by the city of St. Helena. And looking at the acreage, which is about 29,800 acres, that comes out to a proportion of the sustainable yield of 14,100 acre feet per year. Within the Northeast Napa management area for areas with overlying groundwater uses for an area of about eighteen sixty three acres, that came out to five fifty acre feet per year. That analysis is in detail in the technical report.

And then the city of St. Helena, appropriative use, which I mentioned, was the three fifty acre feet per year. So all total, that comes to the estimated sustainable yield of 15,000 acre feet per year. This also, as commissioner Brooks mentioned, it it relies additionally upon looking at, you know, related to the 10% reduction, the voluntary efforts that are could be engaged in further and promoted by the county since March, I believe, 2023 as water conservation as a Napa way of of life. So to summarize, these proportions, you know, by these three areas and then the translation to the water use criteria, the Napa Valley floor at the 14,100 acre feet per year and with the acreage that I mentioned, that translates to the 0.5 acre feet per acre.

The Northeast Napa management area is five fifty acre feet per year, and that was 0.3 acre feet per acre. City Of St. Helena is three fifty acre feet per year through the city's designated safe yield. And this is an approximate number. The city would also be interested in knowing about any projects that are done within its city boundaries.

It would be a half an acre foot per acre. I'm going to turn next to the Tier one, the site specific recharge analysis. As part of WAA procedures for parcels located outside the Napa Valley sub basin, applicants have evaluated the potential recharge for their parcel, which also informs the estimated average annual groundwater use that may be supported. In previous analyses, sometimes these have utilized the recharge results that were developed as part of the county's twenty thirteen updated hydrogeologic characterization work, and that included a recharge analysis as well. The county very much appreciates applicants' interest in expediting the Planning, Building, Environmental Services review of WAA information.

And this led to developing a streamlined methodology. This methodology uses recharge estimates developed based on the US Geological Survey's Basin Characterization Model. This is a simple grid based model that calculates the water balance for any time step or spatial scale by climate inputs, precipitation, and air temperatures. The geology in the area of the model for this purpose was refined based on Napa specific geologic mapping and also hydraulic conductivities, the aquifer parameters that are based on updated geologic characterization in the area. And then the basin characterization model is rerun with this updated geologic mapping and hydraulic conductivities.

And this led to mapping of recharge results that could be used for site specific parcel analyses. This slide shows an aggregated view of these results, but in the next slide, I'm going to show higher resolution results. And it is the higher resolution results that would be served up on the county's website for use by the applicant. So I'll touch on that again in the next slide. But just remember, there are higher resolution details that can be used by the applicant for this streamlined methodology.

There's also the utilization of a ten year period of precipitation data. This is PRISM data for the period 2012 to 2021. This is an average of precipitation over this ten year period, and it reflects generally drier conditions compared to looking at a longer period of record. This provides a consistent way to estimate recharge over a representative period rather than trying to accommodate different approaches using various water year types. So again, the applicant would have available the PRISM results for use with their site specific parcel analysis, and that would be on the county's website.

And then lastly, there's site specific information, parcel size, and looking at the slopes within the parcel area. Similar to past procedures, slopes with greater than 30% are considered more prone to runoff rather than infiltration of precipitation. So parcel areas with steep slopes are excluded from the computation. The applicant would again use slopes, and these are in higher resolution or will be on the Napa County's website. Alternatively, if applicants feel that they have additional site specific information that they consider to better represent site conditions for estimating recharge, then the applicant can elect to do a site specific analysis conducted by a registered professional.

And this analysis would need to be supported by thorough documentation and data that are used to estimate potential recharge.

Could I ask, have you guys I like this. I mean, I think this is really going to help the applicants with the difficult analysis that can sometimes be expensive. We could look back even over the last year that we've looked at where we've seen people use different models and taken different approaches. If we applied this to those cases and then looked, is this being more generous or less or is it sort of splitting the difference between the different models? Do we have a sense of invoking this and making it simple, which seems good? Are we also still being, you know, rigorous enough in terms of what we're really allowing for recharge?

We believe so. So a good example is in the MST where there's already been a lot of study by the US Geological Survey back in 2003 report in in the water levels and geology and everything else and that their, percent recharge in that area comes out to about point three. Elsewhere in the entirety of the county, we see very limited recharge available, especially on the eastern side of the county. And there's little data. So this is based on what is known from surficial soils mapping, infiltration characteristics, geologic mapping, US Geological Survey, and others.

Altogether, including slopes, it's coming up with very, very low recharge amounts. So that's where applicants may think that there's a different alternative. However, we feel that importantly, the hillsides are vulnerable to drought effects and hotter drier temperatures, in particular. Recharge near the sub basin boundary is important for subsurface inflows to the sub basin. But it's also important elsewhere in the hillsides to support healthy ecosystems and other land uses.

So for land uses that rely on groundwater incorporating all this information, We feel that it provides reasonable information and a reasonable assessment of the potential for replenishment. A big concern is that land uses in the hillsides, they're more vulnerable to climate extremes. And in these hotter, drier times, it's, concerning, you know, to count on water sources that are constrained by, limited water supplies and fractured rock and that are very difficult to replenish because of the consolidated rock formations in which that groundwater resides.

Thanks.

So this slide is showing the three images I mentioned just a moment ago about the higher resolution detail, particularly for the percent recharge for the soils and geology, and then the slope delineation. So these are the GIS maps that would be made available through the county's website for applicants to use and then more readily compute a recharge estimate for their parcel unless they choose to do their own specific analysis.

So for 10 acre parcel or what is this one meter resolute? What what resolution do we have here in these maps? Do you know?

I think I'd need to cross check that. I think it's 30 feet. But yeah. Okay. Then turning to Tier two on the well interference criterion, I want to highlight some key aspects of Tier two.

Like the 2015 WAA, the 2026 WAA includes tier two analyses for wells proposed to be located within 500 feet of a neighboring well. The Tier two well interference criterion is presumptively met if there are no neighboring wells located within 500 feet of the applicant's existing or proposed well or wells. New or replacement domestic wells plan to be located within 500 feet of a neighboring well. These should be cited as far as is feasible from the neighboring wells, recognizing that they don't pump as much as for other uses. For springs, projects located within 1,500 feet of springs where potential impacts of pumping are possible but unknown, that may require consideration and analysis of potential impacts on biological resources and other beneficial users that may be impacted.

And oftentimes, this is much more complex and much more difficult because of lack of information and may require site specific investigations. The 2026 WAA clarifies the methodology for doing these analyses, and this is in Appendix F of the WAA. On this slide, there's some summaries of the Tier two considerations. The evaluation of potential well interference includes characterizing the site hydrogeology. This can partly come from the numerous documents that have been developed within the county.

There's also an importance of understanding the construction of on-site and neighboring wells. This can be done either through the database that the Department of Water Resources has online, and the county has its own database and could help the applicant with an understanding of the wells within their area. And then the applicant would be or the registered professional assisting the applicant would use an established method of analysis to estimate the potential drawdown. The well testing may also be involved to ensure that the project includes an adequate and reliable water source or, in some cases, to further evaluate potential well interference. The WAA refers to the California Code of Regulations sections for constant rate testing in unconsolidated, otherwise such as alluvial deposits, and consolidated formations such as the Sonoma Volcanics.

The minimum test length is typically less in unconsolidated formations, approximately eight hours for alluvial type formations, and typically twenty four hours for more consolidated formations. Except for wells in consolidated formations, depending upon the project type or the season in which all of this analysis is occurring, then a longer test may be appropriate. And that would be part of a plan that should be submitted to the county describing the planned test based on the project considerations.

So if I could ask a couple questions. In reading through the document, and something we wrestled with here as we've looked at applications is well testing. And what I was really hoping for in this document was we've been presented with cases where we're shown an airlift test from forty years ago and told that's the production of that well. And I would have loved to see the criteria that says you need a well tested like you were just describing, Vicki. Within three years of this, earthquakes sometimes just destroy wells completely or disrupt their productivity.

And so when we're trying to analyze what an applicant wants to do and especially when they're potentially increasing the draw on a well, I'd like something fresher than 20 or 40 years old. And we don't seem to explicitly address that here. The other thing, if I could do this as a two parter, what you alluded to, which is not a two hour airlift, but some kind of extended test. Typically, what you're looking for is to stabilize the drawdown. So you'd like to do the test and then see it come to some new level and stabilize there.

Because you could do a twenty hour test, see that you're still drawing down. It just has to do with the aquifer, confined, unconfined, what's going on in there. Is it too complicated for us to put some criteria like that to say when you're coming forward and you want to take this well and you're making a major change, this is the right way to characterize a well's capacity and performance?

Very good comments. I'll try and hit a few of those. So on airlift, quote, testing, that's a very poor way to evaluate essentially anything. So it it is not an eligible type of test to meet the criteria. It would need to be more of a constant rate test, which is exactly what you were describing, looking for, the well to be coming into equilibrium with the source of supply coming to the well through the production at the well.

So that's the type of test that would need to be conducted. And it could certainly be described with some other guidance or reference to other guidance documents. One of the reasons for requiring a registered professional is that they should have that knowledge to understand the purpose of the test, the selection of the type of test method, and the actual implementation of the test. So the project type also makes a great deal of difference. You know, if they were needing to rely for domestic well purposes, they had sufficient storage on-site, and they were able to demonstrate that there's not an issue when they're pumping at a certain level in order to have a reliable water source, that's one thing.

But if they were larger projects in the hillsides, then it wouldn't be out of the ordinary to say, well, maybe it needs to be a three day test or a seven day test or longer, depending upon what the fracture geologic setting is, which is largely unknown in most of the areas in the hillside, except where it's been more heavily studied like in the MST.

I guess, yeah, that makes sense to me. I think you said, yes, we could. It's possible to be a little more prescriptive. But with the kind of caveats you have there that it is somewhat dependent on the structure of the soil, but you need to do the appropriate test for the environment that you're in. Like bringing the well at the pumping speed you think you're going to do into equilibrium might be a way to say it where you actually haven't described a specific test you have to do, but basically establish an equilibrium condition for the well.

And I can't remember if in the past we had it, but I did notice in here that we are asking them to tell us what is the the pumping rate they want to do, the frequency and the duration of the pumping rate, which I can't remember if we asked for that before, but I know that's in here now, which I think is a really good thing. Sometimes when we look at it, it looks like they're saying they want to run the well 1% of the time, which isn't really a smart way to run a well. So actually requiring them like it looks like this document does to tell us what your methodology for using this well is a good thing. I applaud that, putting that in there.

Those are all very helpful comments. And one other thing about the airlift testing, sometimes it can be misleading because of the numbers that are recorded on the well drillers' reports. And it can misrepresent what's actually available as a reliable water supply.

I just wanted to make a comment since we are I mean, with respect to your presentation, maybe this is something we can just make a note of to discuss after your presentation. But I am curious about what we're talking about in terms of different types of tests since we have had projects that come in and they have data on well testing that could be decades old, well tests can also be kind of expensive. And so I think trying to balance how do we get more meaningful current data without overburdening you know, especially smaller kind of projects, where it becomes kind of this like pay to play who can pay for the privilege of doing a project. So I mean, I know there's like static water measurements that can be done that are less expensive potentially than full pump tests. Or maybe there's ways that certified engineers can validate old pump tests.

I'm just curious, like, what the expanse of options are because I agree with Commissioner Brooks that it would be nice to have more validation of some of the older layers of data. But I just don't want it to become, over burdensome in that part of the process either.

Very good comments. Commissioner Moran Williams, you asked if we could come back to this. I'm not sure whether to say more now

or I guess I was leaving it up to you to decide if you want to respond now or if we want to discuss it. I mean, you have a response now, I appreciate it. I'm also happy to.

Yeah. I think it's very important to understand the value or benefit of the testing in the context of the specific project. If it's a domestic well within the valley floor and understanding that they're not very near their neighbor, then maybe there's a much lesser need for much at that location. If they're within this 500 feet, but they're able to reposition their well and in consideration of other things. However, if they're in the hillsides, a static water level in and of itself won't provide information on the reliability of that water supply.

So if they are wanting to have more confidence in the water that they have available for the land uses that they're planning to invest in on their parcel and to have potentially water and storage for fire protection or other things, that the value of that test becomes greater.

And just to add on to that, and Vicki touched on this briefly. There are different ways to achieve compliance to the tier two analysis depending on your use. Domestic use is a very different process, and we'll get into this in in a little bit here when I start going through examples. But, obviously, the easiest and best way to achieve this is to move your well 500 feet away from a neighboring well. And so proximity to that neighboring well is really another thing that applicants and property owners can consider.

Domestic and versus agricultural wells, we're gonna be treating them a little bit differently. We'll get like like I said, I will get into that a little bit more. And so there are different processes and characteristics to different land uses, proximity to these neighboring wells and at Springs. We we are touching on neighboring wells, but this the tier two is applicable to springs within 1,500 feet of these wells as well. And so, again, they're treated differently.

We have different ways processing these. To Vicki's point, this is really about ensuring that you are not impacting your adjacent neighbors well for their water supply. And so I think there there is an importance to have these testings. And And as I said, we'll get into this a little bit more as we progress through the presentation.

So Patrick, yeah, I agree with that completely. And one of the things when I was looking at this is we say you can do it by analysis, right? So you look at basically the conductivity of the soil structure. But we have seen some of the applicants actually approach their neighbors and monitor that well while they do the draw. And that seems to me to be the number one and preferred way, but we don't actually say that here.

Don't think or I missed it if I'm reading through here that the best thing to do would be to get an agreement with the neighbor and have that well monitored while you do your test. Sometimes neighbors don't agree or whatever and then you're going to have to fall back on modeling it and using a numerical model and your best guesses and whatever data you have on the material that's in the inner space between the wells. I would love to see us kind of emphasize that as a county and say your best method for doing this is to work with your neighbors and do a coordinated test.

That would be ideal. Yes.

Okay.

Yeah. But I and to your point, this this obviously obviously, as we've seen, neighbor relations plays a big role in that. Yeah. And so, I think one of the reasons why that is not a requirement is due to that civil relationship piece.

Yeah, no, and I wasn't saying it should be a requirement, but I think we can express our preference and what gives us the most confidence when you come in. So, I think that can motivate the applicant to, you know, work hard on trying to get that arrangement with their neighbor.

I'm going to turn now to tier three, groundwater surface water criterion. 2015, WA included the first criteria for consideration of groundwater pumping and the potential for streamflow depletion, And that included analysis of site specific information to evaluate the degree of hydraulic connection to the river, and this included the distance to surface water, the depth of completion of the well or wells, the site hydrogeology, and streambed properties, if they're available. What's been found is that this analysis is oftentimes very complex, very time consuming, and expensive to be able to calculate the potential effect of the proposed project on streamflow and to demonstrate that the project would not result in a significant adverse effect. So now, in the 2026 WAA, it's requiring information sufficient to support the groundwater sustainability plan and, importantly, public trust considerations to ensure the protection and enhancement of groundwater quantity and quality for all beneficial uses and users of groundwater and interconnected surface water, and to achieve the sub basin sustainability goal within twenty years of the Grower Sustainability Plan implementation. The county needs to do its part to take public trust into account as part of the permitting process and to facilitate applicants' efforts to demonstrate no significant adverse effects would occur due to groundwater use near streams, the 2026 WAA includes new protective standards.

The tier three criterion is presumptively met if there are no significant streams within 1,500 feet of the applicant's existing or proposed wells. The significant streams this is mapping that's been updated by the county utilizing the US Geological Survey information, but also augmented with Napa County Resource Conservation District, the RCD's, biological information. This is available online for applicants to use on the county's website. There are detailed, long, involved tables in the 2026 WAA on the tier three requirements. Some aspects of the tier three criteria include metering and reporting, depending upon the proximity to significant streams and the well type and project.

For example, new and replacement domestic wells located within 500 requires metering and reporting. Any project within 1,500 feet of significant streams includes efforts to implement and or enhance water conservation best management practices. These practices aren't being put forth as prescriptive requirements. Applicants would complete a water conservation declaration form describing what types of conservation activities are already occurring and what other activity or activities they can add to their water conservation portfolio. And Patrick's going to show and describe an example of that with some WAA examples.

If the project includes a new or replacement well, a 150 foot well seal depth would be required as a protective measure. There are analyses in the technical report that go through how that was derived by looking at distances from the stream, different completions of the well relative to the stream, and looking at what would constitute a reasonable protective measure to reduce streamflow depletion with groundwater use in closer proximity to the stream.

So that 150 feet, I don't remember. That's a new criteria that's stricter and trying to get the screening on the well and everything below where it might interact with stream bed or whatever. That's the goal with the 150 foot seal?

Correct.

Correct.

And a seal versus screening, right? I mean, there's a sanitary aspect to seals. There's also just pipes with no screening. And so you don't start your screening until 150 or 200 feet or whatever below. Are those equivalent or is the seal itself important here in asking for 150 foot seal?

The seal itself is important because you could have a shallow seal and screens at a greater depth, but then you can still have effect through the borehole and the draw on the, you know, as the groundwater is producing from Excellent. That

No, that's good. That's great. That looks like it is.

So if the applicant can either meet the water use criterion when they're located within proximity to significant streams, or they need to show, demonstrate to the county that public trust considerations have occurred during their project design and operation, and they would need to demonstrate reduced streamflow depletion. Through the implementation of these new protective standards, we see the types of project applications that may require more complex, involve time consuming, expensive modeling effort for the tier three analysis would be reduced because of the protective standards. But they're still depending upon what the direction of the project is, it still may be required. And I'm going to turn it now to Patrick for WAA examples.

I just want quick clarification. So this tier three, these are new mandates with the tier three depletion analysis specifically for projects within that 1,500 feet of streams, correct?

Correct. And the different standards vary across the well type and the distance from the stream. But all of them require water conservation declarations. They're explained in detail in these long tables, and Patrick's going to go through an example of a couple of them.

Yeah, just to add on to what Vicki said, this is again a more streamlined approach for applicants to use. This creates a process in which I would consider you can kind of go through a menu of items to comply with our tier three requirements. An applicant still can choose to hire a hydrogeologist or a design professional to go through an analysis to demonstrate that an existing well or proposed well is hydraulically disconnected. So again, there there are alternatives to this streamlined process that applicants can choose. It's not just one size fits all.

Let me ask, we saw a couple examples, you know, historically, you know, some of these properties go back fifty years. We've seen wells drilled essentially right next to stream beds. And I was trying to, you know, was thinking an analogy to if I want to modify my house and I'm applying to you guys for a permit and I'm changing more than 50% of the house and I'm remodeling it, then I have to come up to all the new standards fire safety codes and everything like that. If I just do a small amount and then sometimes those standards only apply to the small square footage. It seems to me like if somebody has one of these wells that's in clear violation of what we want, you know, they're basically in the stream bed, they're not 500 feet away, that if you come to us and you say you now want to double your production and double your visitation and increase your water use, then I'd love to see it where we go, okay, but you've got to make your water right now in the same way we make you come up to code when you make a major change to a building or a house or whatever And I don't know whether that's in there right now.

If somebody has a well that clearly probably is in a stream bed and is affecting the flow, you know, we allow them to keep that now or do we insist that they correct that problem before we would let them have a major mod and say double their production?

Let's okay. So we have a a historical well that may be potentially this is hypothetical. So if we have an existing well that's shallow in the alluvium, very close proximity to a significant stream that we identify that there is streamflow depletion occurring based on operations. And let's say that project was evaluated ten years ago and public trust considerations were were not evaluated as part of that consideration historically. I would argue that as as the authority having jurisdiction over this in Napa County, we would be we would be obligated to require that applicant or that property owner to mitigate, to reduce harm to those public source to those public trust resources.

Public trust is a is kind of one of those evergreen laws. It's kind of outside of CEQA. And so if we see a public trust impact, we have an obligation to mitigate for it. And so, to your point, and I'm gonna quote our director, the goal is to I think the goal or the objective is to get these older, wells offline if they are truly creating an impact. And in some circumstances, a project through its analysis may require mitigation, and one of those mitigations may be to relocate the well, or to provide, or or to modify that existing well to create a a further seal depth to do to go deeper.

And and so we had kinda we're gonna evaluate these on a more project by project basis. For your example, though, we will be evaluating that well as part of that project. It is a groundwater source for that potential use. And so we will be evaluating the existing condition and the proposed condition as part of that analysis.

Good. Thanks.

Okay. Well, we gave you a bunch of technical stuff. So we're gonna try to kind of identify how we apply these. And let me just get back to where I'm at here. So we're gonna give you three examples today. I'm gonna go through the first two fairly quickly. We're gonna talk about maybe we're gonna talk about a new domestic well, a replacement domestic well, and something that's more in line with what you all see on the planning commission, a a winery project. I have an example of one of the tables or the regulatory matrices that we have in the WAA guidelines to the right. This is table one dash two, and this is specific to domestic wells. This is just an example of what you'll find in the WAA guidance document.

We have many tables that represents how the regulatory process is going to be applicable to you and your water source based on your location, proximity to significant streams, and the land uses that are associated with it. So to get into the first example, we have a new domestic well on the Napa Valley floor. And so for this applicant, we would be evaluating this through the new WAA guidelines. And to satisfy the tier one requirements, because this is on the Napa Valley floor, the applicant would be required to only extract their water use criteria would be 0.5 acre feet per acre and no more than one acre feet for residential use per year. The applicant would be required to complete a water use declaration in which they identify their water extraction volumes.

And when they submit that as part of their application submittal material, we would consider that Tier one complete. To handle our tier two requirements for well and spring interference, in this circumstance, this new well is not within 500 feet of a neighboring well and is not within 1,500 feet of a existing spring. And so as part of staff's review on this and the applicant's procedure for representing how they are complying with this, they're really gonna provide staff a map that demonstrates that this new water source is beyond those linear thresholds. So 500 feet from neighboring wells, 1,500 feet from springs. If the applicant provides that information to staff, we will consider the tier two complete.

For the tier three analysis for interconnected surface waters and our public trust considerations, Hypothetically, this well is within 400 feet of a significant stream, specifically the Napa River in this circumstance. This would trigger the tier three analysis. Because this is a new well, they would be required to demonstrate so this is table two dash three, which is the tier three regulatory matrix. So to comply with our interconnected surface water requirements, The well would be required to have a seal depth to a 150 feet. The well would be required to be located as far as feasible from the stream, and this is gonna be really based on the site considerations.

And they will be required to implement water conservation management practices, which would intuitively reduce groundwater demands for that particular land use. The applicant would also be required to meter and monitor and report the well data in the volumes of extraction on that specific well. So this gets into the water conservation declaration form. This is where the applicant would actually be identifying existing measures that are they are implementing as part of their kind of land uses in their property and just managing their property, as well as planned measures, water conservation measures that they would be implementing to again intuitively reduce consumption and be more water groundwater efficient in their operations. So as part of the water conservation declaration form, the applicant would be kind of identifying what existing measures and what proposed measures they are.

As Vicki described earlier, these are not prescriptive. This is kind of a menu of items applicants can choose from. They would submit this water declaration form and staff would consider our tier three obligations complete. Okay, our next example

Could I ask?

Oh, absolutely, please.

So, going back to that one, maybe a couple of charts back, one more I think. So 0.5 acre feet per acre, which is our standard draw versus recharge, but an acre foot per year, 325,000 gallons a year for a single household. In the MST, we're saying 0.6 acre feet per year. You know, that's approaching 800 gallons per day for domestic use, which seems really high. And I wonder why, again, this isn't a commercial thing.

It's domestic use. Some counties and a lot of places, it's more like for a single residence, it's a half an acre foot per year and we are doing that in the MST. Why are we allowing kind of an acre foot per year for domestic? Is that just have we always done that? Or is there a rationale for why that's a reasonable amount of water to use for a house? You want to try this one?

So one of the things here is that we're looking at groundwater use by self supplied water supplies, so individual wells. So there is also the likelihood that they have more than a, like, a city, like, residential lot. So in order to accommodate some of that, it's looking at a little larger groundwater use. It doesn't mean they need to use up to all of that. And as we're describing earlier, the county is wanting to emphasize water conservation.

So we're trying to keep it, you know, equal and fair and consider, you know, all of the users across the area for which the water use criterion applies. So that's how in the Napa Valley floor, it landed at the 0.5 acre feet.

Right. Yeah.

And I would add on to that. Our existing land use, we we do allow multiple dwelling units on a parcel as well. And this has been really emphasized through the state and existing kind of state bills and assembly bills that have gone through and and staff and working with council and Ludorff. We felt like one acre feet is the is a reasonable extraction value to allow those buy right uses for residential individual use.

Yeah. If there were ADUs or multiple houses on a single property, then I could see how the acre foot would be. I just sort of translated this to a single house kind of thing, not sort of a compound or whatever.

Okay, moving on to my second example. This is a replacement domestic well. So, old well, something happened to it and they're just replacing an old well, domestic well with a new domestic well. This project is located in the Northeast NAPA Management Area. And so as we evaluate a project in with this scenario, a tier two because this is a groundwater use project, it would trigger the tier one requirements.

To satisfy the tier one requirements in the Northeast Napa Management area, the applicant would be required to their water use requirements would be 0.3 acre feet per acre and no more than 0.6 acre feet per acre for residential uses or no net increase based on historical groundwater extraction. They would also be required to complete the groundwater use declaration. This would then satisfy our tier one criteria. For tier two criteria, this well is located within a 100 feet of a neighboring well, but outside of the 1,500 foot threshold for a spring. Because they are within 500 feet of a neighboring well, a tier two is required to satisfy the tier two requirements for this domestic replacement well.

We would just be we would require that applicant to place that replacement well as far away from that neighboring well as possible. And in addition to that, I'd emphasize that we'd want that new well to be further away than the existing well. So we wouldn't want that new replacement well to go closer to the neighboring well. We want it to either stay the same distance or further away. That that again is kind of one of those insurances that we are not exacerbating or making things worse for that neighboring well or that spring.

For the tier three requirements, this hypothetical project water source is within 1,500 feet of a significant stream. And so to satisfy our tier three requirements Oh, yeah. I'm sorry. This is the parcel is wait. I'd lost myself here. Sorry. I apologize for that. Okay. I'm sorry. This one is further than 1,500 feet from a significant stream. So there it's just it's considered not having an impact and the Tier three is satisfied just through distance.

Maybe a time to bring it up. If they were using per acre or or two acre feet a year instead of the one, you know, we basically grandfather that in. As long as they don't say they're going to increase it past that, even if you were a factor of two or three over what we'd like to see you doing, we just leave it alone. And that's how we're treating this here.

Well, would have to demonstrate through the demand analysis that the uses on that parcel are actually going to require that two acre feet. And so this two acre feet, that's either a very large estate, or or it, potentially has multiple uses on the property such as agriculture, which is a different scenario here. But if, let's say, they do come in, it's one of these larger estates on the Valley Floor and they say, yeah, I'm pumping two acre feet because I've got a lot of turf. I got a lot of irrigation, swimming pools, reflecting ponds. I mean, you name it.

We've seen it. If we can justify that existing demand, they would be required to to to own an increase provision.

Good.

Okay. My final example here is a winery project. This is something that you guys are familiar with. It's located on a 20 acre parcel on the Valley Floor. Its current water use from a non project well is 15 acre feet per year.

And as part of the project, they are proposing a new well. So this is a groundwater use project and so a tier one is required. For the applicant to satisfy the tier one, they will be required to provide Napa County staff with a water demand analysis and demonstrate that they are either extracting at the 0.5 acre feet per acre or if they're exceeding that water use criteria, they would be subject to the no net increase provision. They would be required to complete the water use declaration form as I explained in the last two examples. And that would that would satisfy our tier one requirements at that point.

For a tier two, there are no neighboring wells within 500 feet and no springs within 1,500 feet. So by just the distance and proximity, the the tier two is not required and we consider that complete. For the tier three analysis, the parcel is located less than 500 feet from a stream and so a tier three would be required for both the new well proposed and the existing well on the parcel. So to satisfy our tier three requirements, we'll kinda look at the new well, the new the new project well that's scoped out for this project. That new well would be required to meet the point five acre feet per acre for those new uses for the water use criteria.

It'd be required to have a seal depth of a 150 feet and locate the well as far as feasible from that that stream. They'd be required to register that well and that would be meter monitoring and reporting as as as part of that registration. Implement water conservation measures related to commercial, industrial, agricultural. We we reference these as WC2s or water conservation measures two. And when applicable, provide a plan to demonstrate public trust considerations during the project design and operation are met.

This is kind of unique that it's only when it's applicable if we see a potential impact to these public sort public trust resources. For the existing well, this existing well would be required to meet the existing water use criteria or no net increase. Its seal depth would not be required. It's an existing well. We would accept the existing seal depth.

That well would also be required to be registered, implement water conservation, best management practices, meter monitor and report. And to ensure that as part of the operations or the startup of this new land use, we'd want to ensure that that well operation doesn't change from its existing operational use. And that's kind of where where applicable, we would be requiring some groundwater management plan criteria to demonstrate that, hey, we are not going to offset uses on this existing well, exacerbate or intensify the use of this existing well that potentially may have impacts. We want to maintain static kind of operation levels or reduced operation levels on that existing well to ensure that we are meeting our obligations under public trust.

Patrick. Go ahead.

I was gonna say reduced operations levels, but based on entitlements or estimated usage.

This is really the when I when I reference reduced operation levels, this is when they implement those water conservation measures.

Or no net increase. I'm just trying the baseline, though, is based on the estimated levels.

Well, we we encourage and emphasize that we want actuals when available. But, when those are not available, we can use estimates based on, I believe it's in appendix a now in the WAA. Used to be in appendix b. And

then just to make sure I'm understanding this, the tier three kicks in this tier three analysis kicks in if the new well is within less than 500 feet of a non project well or within 1,500 feet of a stream?

Yeah. So this is the Tier three, so it's really related to significant streams and distance So of significant in this scenario, both wells, the existing well and the new project well, are within that 1,500 foot buffer. And so to satisfy our obligations under understand the existing operations of that existing well to ensure as we move forward in these new intensifications of land uses on that property, we don't increase extraction on the existing well to exacerbate or create a new impact that necessarily wasn't there as we've been evaluating it. And that's really the reason why we're going to be registering these existing wells even though it's not a project well. We just want to ensure that because now it's a kind of a integrated water system on this parcel, multiple water sources serving multiple uses, staff really needs to understand how those uses are being served by these wells.

Is it is it a combined water system? Is one water system supporting only one land use? And so by understanding this through the tier one, this is the the demand analysis, this sets us up for the tier three to understand what provisions, what requirements need to be imposed on the project to ensure we're not creating impacts, to to ensure that we're not exacerbating potentially existing impacts. And so this is kinda where we get into a more integrated analysis on all water uses on a property even though one well may not be subject to the project. We just have to understand everything.

And we really emphasize to applicants today and we'll continue to move forward as part of the water demand analysis. They really provide us a granular understanding of how water is being used on the site for different land uses. If it's an integrated system, we need to understand that. If there's ones being if there's, yeah, it can be really complicated, especially when you get multiple wells on a parcel serving multiple uses.

So, Commissioner Moran Williams referenced the entitlement versus actual uses and we did wrestle with that in this last year and so the example that comes to mind was somebody who had an ECP and was approved to plant five acres and was approved for water use to irrigate those five acres of vineyard, but had only planted one acre and then they were proposing a winery, but in terms of and were arguing they didn't need to do a tier two or three analysis because they were using less water, but we didn't know how much water they were using. They hadn't built the winery yet, had only planted one acre and yet they took this entitlement for when they had fully built out the five acres to say that they were going to decrease their water use. And I would really like to see us insist that we have some kind of, like you said, estimate or actuals of what are you drawing, because to me the tier two and tier three is to protect against interactions when you increase the draw. And even though technically you're entitled that water, you haven't started to draw it yet. So we don't know whether it's really gonna affect a neighbor's well or affect the local stream because you're gonna up your pumping by a factor of two or three over the next few years as you build the winery and the vineyards out.

And so what are you using right now and then what's going up? It seems like it's kind of used as a get out of jail card for not having to do tier two and three analysis by, you know, invoking your entitlement and saying, well, I'm using less than my entitlement. I was hoping we would wrestle with that in this document and insist like the well test where we'd like a well test within the last three years, we'd like to know what you're actually taking out of your well right now and then are you increasing that at all in terms, and it's not saying that they couldn't do it, but you should do the tier two and tier three if you're going to double the extraction rate, then your chances of interference, you know, would go up significantly.

This is a complicated question and I'll try to dive into a little bit of it right now. So as far as the tier two goes, as Vicky kind of explained earlier, and I think we can get into based on your recommendation that we received today, a little more explicit prescribed requirements. My understanding is that the tier two, when you when you perform that pump test for that tier two, you're gonna wanna perform that pump test based on the operational characteristics of the entitlement because we are we are in evaluating well, we historically and currently evaluate projects based on entitlement and the proposed uses based on whatever project that we're we're seeing in front of us. We could don't see if we ask for the existing demands, I mean, that that's fine, but that's not what staff is currently using as part of our analysis. So it it'll just be more of a placeholder documentation of what hey.

We're not operating at our entitled use. This is kinda what we're doing here. What that could do is help project for entitled numbers. Hey, I'm currently operating at 60%. This is my actuals at 60%. That really helps project to a 100% operations or entitlement operations. I would argue that's a really good exercise to do. In lieu of using estimates that we find in the 2026 WAA and appendix a, in the 2025, you'll find it in appendix b. But those estimates that we use in our document, those are just estimates. And for me as an engineer, I think projections may be a little bit more accurate, maybe not precise, but more accurate.

And so, yes, I think by utilizing existing operations to project to entitlements is a good exercise for applicants. For the tier two, as I kind of as I've mentioned, the tier two analysis and the pump test, those pump tests should be based on your operational and I would emphasize, and if we need to emphasize this in the guidance documents, based on your entitlement so that we can demonstrate impacts or non impacts based on those pumping rates and and frequencies for a an entitled operation. For the tier three, I I think I brought this up earlier. If if a project performs a tier three analysis or there's evidence in the record that demonstrate that there is a potential impact for them increasing their extraction volumes and frequencies could cause or may cause an impact to public trust, staff would be obligated to mitigate and act and to reduce harm. Even if that means, hey, we got to reduce your extraction numbers to reduce that harm to those public trust resources.

We would have an obligation to do that. If there is no impact at that entitled use and they meet the criteria or the regulatory provisions outlined in two dash four for meeting a tier three requirement based on the way the guidance document is is written and presented today, that would satisfy us. I I hope that answered majority of your questions.

No. No. Didn't. I like the idea that, you know, if we're prescribing and we want you to do the test, do your even if you're only pumping at 10 gallons per minute, but when you put your winery and vineyard together and your future demand, then do the test. You're going to do a 50% duty cycle, so 30 gallons per minute. So do it at that level and then do the analysis of the Tier two and Tier three analysis or even better if you've gotten your neighbor to agree and you're actually seeing the drawdown that will happen when you get to your full draw, that would be the ideal thing to see and that's basically kind of what you're saying and I like that. So if we can somehow build that in so people get it, that's how we would like to see it analyzed, that's fantastic.

Can I just add one thing? Just to clarify, there's no entitlement to a particular level of groundwater use. So, think when Patrick's referring to entitled operations, he's talking about a use permit that has an entitled business. But it doesn't mean that that permittee has an entitlement to extract a particular amount of groundwater.

I actually thought I'd heard the opposite of that previously in one of our projects where they had an approved ECP and they had been approved for a certain amount of extraction and they considered that an entitlement that they were and that's not how it works?

Correct.

Okay, so what do they have?

They have an entitlement to those operations, but they don't have an entitled ability to extract any particular level of groundwater.

Okay. And then not having that, then they have to justify that extraction and show that it's balanced through the analysis that we're asking them to do?

Well, Patrick said, if it's showing that there's an impact, they would have to do something to offset that impact so that there wouldn't be an impact on public trust.

Okay. Thank

you, Laurie. Yeah, and just to clarify, I am talking about entitled land uses, not extraction volumes. So just to clarify, I am when I say entitlements, I'm talking about the land uses approved through either this commission, the board, or the zoning administrator. Okay. I'll just complete this.

So I think I already actually went through this, but just in case. Okay. So as I kinda mentioned to satisfy the tier three requirements, the applicant for both the new well proposed for the project and the existing well serving existing uses, they would be required to meet the criteria in Table two-four, which I believe I went through and I won't go through them again in the interest of time. But if they demonstrate satisfaction to all this criteria that you would find in Table two-four, we would consider both wells satisfactory and complete as it relates to interconnected surface waters and those impacts. Okay.

That kinda gets us into our next steps. So to summarize, the 2026 draft water availability analysis is is an update and an improvement to our existing 2025 WA guidance document as well as, integrating our inter our 2023 interim well standards, which identifies water use criterias for the four areas identified in this presentation. That would be the Napa Valley floor, Nima, the MST area, the groundwater deficient area, and all other areas. No net increase for new replacement or existing wells with new or increases increased uses on properties where existing uses exceed water use criteria. This is a current and will be a continued provision that we would implement in Napa County.

For tier one requirements outside the Napa Valley sub basin for the MST in the Northeast Napa management area, water use criteria of point three acre feet per acre or no net increase, will be implemented. And then for all other areas that's outside the Napa Valley floor, the Northeast Napa management area, the groundwater deficient area, a site specific recharge analysis would be required. We are now proposing an alternative or a streamlined approach in which applicants can go to our GIS system and really simply calculate their recharge based on the recharge factors that are identified in GIS, all areas of the parcel that are less than 30% slope, as well as the precipitation data from the ten year PRISM data that we described earlier. For the WAA for tier twos and tier threes, The tier two has been really unchanged. We've just clarified and provide more information and detail about how to perform this analysis and present this to the county.

So we clarified methodologies there. For the Tier three, again, Tier three, what we've tried to achieve here is a more clear and concise way of implementing and demonstrating compliance with the Tier three, as well as implementing the regulatory matrices as a more streamlined streamlined approach for applicants in lieu of hiring a hydrogeologist and performing a interconnected surface water analysis, which can be very burdensome, voluminous, and expensive. So for the next steps, we encourage, all members of the community, our stakeholders, our design professionals to review these two documents. They are large and detailed, but we did that for a reason. But to participate in this public comment period, again, public comment will close on close of business on May 26.

And we are continuing to respond to comments. We encourage industry groups, special interest groups to contact us if they want kind of targeted outreach or targeted questions and concerns that they have. Like I said, we are encouraging participation. This is this is what this is about. Following the close of public comment, we are tentatively scheduled to go to the board in late July at which we would be presenting the final draft as well as responding to those pertinent comments that we receive as part of this sixty day comment period.

With that, I really appreciate your time. We took up a lot of your morning, but at this time, Vicki and I are more than happy to answer any questions from you or the public.

So, just want to say, I mean, I've obviously been asking occasionally about this and I'm really impressed with the document. I think some of the streamlining you did in the recharge is really going to be helpful for people as they try and move through this and you seem receptive to some of the comments that I've made about how we maybe can get a little more detail on what's going on with the wells and what's really available in water. There was, I think there's a placeholder in there for a checklist maybe, but it's not in there yet. Is that right? At least the copy I had didn't have the and we've gotten some feedback from, you know, our applicants and other people, you know, who are looking at what we're doing about it, you know, our checklist really complete and does it really, you know, outline the process?

And if you really do that, then you've you've done all the steps. So I would if if that is gonna come out for comment too, I'd love to see see the checklist.

So, we we left it as a placeholder, because we this is a draft, and it's subject to change. Right. And so in instead of, spending resources and time developing a comprehensive checklist, we wanted to wait to make sure that we we address all the comments. And if there's any changes, we can implement that or include that as part of any checklist moving forward. But there is a placeholder. It's there for a reason. We will have a checklist as this thing is rolled out and is finalized.

Well, good job on this.

Thank you so much for walking us through all of that information. Super helpful. We will go to public comments. We'll first start here in the room. And if you wish to comment, please feel free to step forward. You'll have three minutes.

Good morning. Peter Nissen speaking on behalf of myself. I have a couple of questions. When you are doing well tests, I've been up here before with personal property, it's important to know when the Wells test is taken. Is it taken during the winter or is it taken during the time of year when the most amount of water is going to be extracted?

I'd also like to know if there's a recovery evaluation. Is that called equilibrium, or is recovery separate where the recovery period, if it's using, let's say, an amount of water that's going to replicate the permit's use in process of evaluating it. I also wanted to know if in fact I was on the ag advisory committee for groundwater, And at that time, they were told that it was a statewide obligation to let domestic people use two acre feet per year. Has that been changed? And likewise, the 2022 governor's executive order, has that been re been rescinded from the point three to the point five where you're you're giving us more water?

And I also wanted to know exactly you said in I think in some of your preliminary discussions, you were going to explain why the well seals were going be at 150 feet, and I don't think you explained that because I think that that's a large factor in cost and why it's that depth, is it going to be determined on a per site basis that it could be less than that and it's not going to interfere with surface water interaction. That's it. Thank you very much.

I'll touch on just a so, yes, the governor's executive order regarding the drought plan has been rescinded. It was rescinded in March 2024, I believe. And that was in one location in which the two acre feet was identified as a de minimis use for domestic use. That that two acre feet is referenced in that executive order really based on what we feel like and the sustainability of the sub basin in Napa Valley. This is where we went to the one acre foot.

Two acre foot to support residential uses is, in my eyes, excessive encounter to the state's initiative on the 47 gallons per capita per day initiative. And if you look at that 47 gallons per capita per day initiative that comes from the state of California, residents or for patrons in a residence, that equates to about 0.23 acre feet, I believe. And so going to one acre foot should be plenty of water to support those by right residential uses on parcels in Nampa County, we feel like. With respect to the 100 foot well sealed, Vicki did touch on this briefly, but if I could ask her to kind of just dive into that one last time.

Sure. So on the 150 foot depth seal, we do have a detailed discussion of that within the technical report, the companion document to the WAA. What that explains is analyses that we looked at based on a numerical flow model to test different distances from the river, different screening ceiling depths from the river, and to look at what would be reasonably protective if you have a well in closer proximity within 500 feet of the river to try to reduce streamflow depletion. So that 150 feet, there's probably a little flexibility depending upon the on-site geological conditions being drilled at the time for which to seal against, but that's the basis of the 150 foot seal depth.

And the 50 foot that we have right now is still the standard. And so the 150 is used when you've got a problem and you've got a proximity issue or whatever and you're trying to protect if you're drilling it. Is that the way to see the 150?

Correct. The 150 is specific to the tier three protective standards. And I'm not sure what is coming out, but it is coming out soon with the Department of Water Resources revised well construction standards. So there may be other guidance pertaining to specific conditions that warrant, you know, other considerations for the construction of wells, you know, whether it's quality or quantity or streamflow depletion, subsidence, or or other concerns.

And just to add on to that, I just wanna emphasize again that this this approach, as you'll find in tables two dash three dash four dash five, these are just the streamline approaches. There are gonna be scenarios in which we have kind of elevation kind of or elevation is is just kinda key here where, hey, maybe your well is above the thalweg of the stream. And if you kinda look at elevations or a profile across section through there, you may find working with a design professional, hydrogeologist, a geologist, and as as an engineer, they might say, hey, you're you are in deep volcanics. And if we look at the bottom of your well and your pumping regime, kind of the the cross section, you're pumping above the thalweg of a stream, which kind of there can't be any interconnection there. There's gonna be scenarios in which you are gonna look at the tables in our WA and say, hey, this streamline approach doesn't really represent my the characteristics of my project and my water source.

And you may want to consult with a design professional to say, hey. Yeah. There's a simplified approach, but I don't think it's applicable to me here. Is there a better way? You can consult with Napa County. We can be a resource for you. We will not do the analysis. That's not our role here, but we can at least guide, coach, be a resource. But there is gonna be scenarios in which the table's not gonna be right for you in your project in your location. And that's why this is more This is an option. This is a streamline option for you. It does it's not a one size fits all. So there we we allow other alternatives provided it's done by the right registered professional.

Great. Thank you. All right. It seems like that's all our questions here in the room. Do we have any folks on the phone?

Yes. So we have eight attendees, and we have three public comments. Great. I will allow the first one, which is Michelle Benvenuto. Michelle, you'll have three minutes.

Hi. Michelle Benvenuto, wine growers of Napa County. I want to address a couple of Commissioner Brooks' comments. First, the proposed point five acre feet per acre per year, criterion represents a 50% reduction from the only standard that ever formally was adopted by the board of supervisors. So On May 1235, the board adopted a one acre one acre foot per acre per year as the baseline criteria.

And that standard was grounded in technical review, monitoring data, and hydrological conceptualization. The 2022 interim criteria of point three acre feet per acre per year was an emergency drought measure tied to governor Newsom's executive orders, which you have heard have been terminated. That interim standard was never adopted by the board and should not serve as the de facto baseline from which a permanent criteria is now being measured. Regarding the 10% reduction requirement, as a member of the Ag Advisory Groundwater Committee that developed this recommendation, I want to be unambiguous. This was never intended to be applied on a per parcel basis.

It was designed as an aggregate reduction across users and that distinction was deliberate. The committee explicitly recognized that a per parcel application would penalize early conservers and we intentionally structured the recommendation to avoid that outcome. Users who proactively reduced water use would face a more difficult path to achieving a 10 than those who have not. So basically, you're punishing the behavior that we want to encourage. Conditioning individual project approvals on a per parcel 10% reduction was never the intent, and that discontinue. Thank you.

Thank you, Ms. Benvenuto.

Anthony, when you're available, you'll have three minutes.

Hi. I'm Anthony Hickey with Richard Slade and Associates, hydrogeologist working in the county and working a lot of these WAAs. Thank you very much for this presentation. Much appreciated. And commissioner Brooks, I just wanted to carry on or or go back to a point that you made in some of your comments about pumping tests and proving supply and what an appropriate pumping test is.

I think one thing that may be unclear or in the last WAA draft and in this one is the language in the WAA that talks about the planned pumping rate of wells, you know, there's a footnote that used to talk about and still does, it's in this version as well, about airlifting rates not being sufficient. That's all tied in my opinion or in my reading to the tier two requirements. And a lot of times being in front of the commission and having questions from commissioner Brooks is, you know, is the well proposed appropriate for the use? Can it pump at those rates? We're trying to prove that, but it's not a tier two situation.

And so the more formal or more robust pumping test that's described in the tier two section isn't necessarily required. And so just just from public comments over time, commissioner Brooks, I think that your, you know, your desire that has been expressed over time and tell me if I'm putting words in your mouth has been more robust pumping tests to improve supply even if it's not tied to a tier two and so maybe some clarification there in the document would help future applicants. And then just another comment, something I took away from today's presentation that I didn't get from the prior was that it seems to me that the way this is structured relying on the state code for public water system pumping tests or at least referring to it not relying upon it is that essentially tier two pumping tests for all hillside properties will now need to have a draft work plan submitted to the county for review and I just wanted to make sure I'm understanding that correctly. But again thank you all for the opportunity to review these in advance and ask these questions.

Thank you, Mr. Hickey.

David, when you're ready, you'll have three minutes.

Hello. David Graves here, perennial gadfly on groundwater. I'm curious, is there an environmental document that will be associated with this? Is this a project as defined under CEQA? Second, I will reserve most of my questions for the written comments that you'll be accepting through the end of May. But I'm hoping that there'll be will there be a sort of a reply matrix as there often is in EIR comments? So that's that's all I have right now. The rest of it, will read in my written comments. Thank you.

Thank you, mister Graves. Staff, did one e one respond? Sure.

Hi, David. And also, we will be doing a CEQA analysis. This is a project subject to CEQA. We are anticipating that it will meet the criteria for one or more categorical exemptions. So we will be preparing a robust sequel memo that articulates how it falls within the exemptions after we get the draft finalized.

Great. Thank you.

Was there one of the public commenters, Mr. Hickey, I think had a clarification question around the tier two process and what needed to be submitted in terms of work plan for that? Not sure if I got that exactly right.

Yeah. I believe his question was related to wells within the hillsides based on the criteria identified in the WAA. His comment kind of reflects that he believes that this would require a well pump operations kind of work plan to demonstrate what the actual operations may be on that well after the proposed uses are implemented. I don't necessarily think that's explicitly required as part of that. For me, I think it's a clear understanding of the operations of that well in its proposed condition is a necessary component of a tier two analysis to achieve the appropriate pump test to reflect if there are any impact to those neighboring wells or proximity springs.

That's correct. That plan for the test.

And I think you made a comment about what my questioning and yeah, I'd be interested in us not just triggering this because we've got a tier two issue. But tier one, do you have enough water? What does that well do? Certainly like the guideline to be that we'd like a current robust test that follows some standards. Peter needs some comment about both recharge and drawdown and stability of the well. I'd love to see that done even if there isn't a Tier two or Tier three issue, just do you have enough water to accomplish what you say you want to do with your winery and potentially vineyard?

Ian, you know what, I do want to address one comment that we received during the tag and that we've received on through our kind of email generated comments. And the reason why I wanna bring this up is because I think I can answer it very simply. The question that has arose is how are we going to apply the WAA when it becomes effective to pipe line projects. And I'm sure you guys are all curious about that as well. And and so a simple answer to this is is we are gonna apply the WAA when it becomes effective like we would any other regulatory change.

If the project is deemed complete, you would not be required to to implement any of the new provisions of the 2026 WAA if you are a current pipeline project. There is a caveat to that statement. Because we see that there are some benefits to applicants and property owners as part of this update. If an applicant wants to voluntarily update their water availability analysis to comport with the new effective standard, even though their project has been deemed complete, that will be allowed. If a project is in process and is not deemed complete and the new standard becomes effective, the new rules and regulations will be implemented on the project.

Thank you. I understand that, mister Hickey, would like to clarify his question. So we're gonna have him speak again.

Alright. I think, yeah. It was just a little misconstrued. I think, Vicky got to it there. I was I was only speaking about if you have to do a pumping test for a tier two requirement to satisfy the tier two requirements, is a work plan need to be prepared in advance and approved before we actually perform that pumping test? That was kind of my reading of the current text and usually how that provision that is quoted in the WA text is applied by the state.

Anthony, I would say your interpretation read of that section is correct.

All right. Thank you.

Just in case if anyone else is on the call in and attendees, if you'd like to speak, please press 9 if you would like to comment on this item. I don't think there's any more public comment on this item.

Okay. Thank you for giving them that last option. Well, was excellent. Just to double check, any other questions or comments? Okay. Sounds good.

Oh, I just you know, I appreciate the presentation. And I think, you know, we've talked a lot about the WAA in in our presentation, our discussions over the last year. So I think this is a real substantive improvement that will help us to understand, just have more meaningful clarity on what the water situation is. And you know, I like some of the things that I've seen in this so far. I'm going to dig into everything a little more deeply.

But I like that we can understand now the methodology for, like, the proportion of sustainable yield that's going to each of these zones. I appreciate this, like, fourth zone added because it means that we have this deeper understanding of, you know, the the landscape regionally, which I think is going to be helpful moving forward. And, you know, I you know, think I think I would look forward to kind of seeing the comments that come through the community as we move this forward. Thank you for all the work on this. It helps us with our, you know, future decision making.

Thank you all. Appreciate it.

Thank you.

All right. Okay, and on to Director's report. I don't recall, Mr. Parker, if you mentioned you had items.

Yes, there's a couple of items. So, we will be meeting, the Planning Commission will be meeting on the 05/20/2026 regularly scheduled Commission meeting. There will be one item before you. It'll be the Paloma code compliance use permit that was continued to a date certain. That is gonna be presented by supervising planner Sean Trippi.

That'll be the only item before you on that date. Since my last report out, the zoning administrator took one action, two actions. The first was approving the Yacht Mill Road Residence View Shed Protection Program and the Terraces Code Compliance Program was administratively approved. And that is it for my report out.

Great. Thank you so much. And lastly, we have commissioner comments or committee reports. I don't have any.

I did attend the Wildlife Conservation Commission meeting and it's an interesting group. I'm enjoying kind of participating in that. We have an amount of funding that gets distributed to different organizations throughout the county, sort of like gap funding to help with different wildlife conservation efforts. And so right now we are in the process of evolving the application process and the grant making process. That's not going to take effect this year.

It'll take effect next year. But we're having, I think, good discussions on how to make that grant program a better process for the applicants as well as for us deciding on how much money to give each organization.

Great. Thank you. Alright. Well, I believe that is everything. So, we are adjourned. Thank you.