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Hydro Visions Official Publication of the Groundwater Resources Association

VOLUME THIRTY-FIVE

OCTOBER 2026

2026 Fall Issue

V.35

Hydro Visions

HYDROVISIONS is the official publication of the Groundwater Resources Association of California (GRA). GRA’s mailing address is 808 R Street. Suite 209, Sacramento, CA 95811. Any questions or comments concerning this publication should be directed to the newsletter editor at hydrovisions@grac.org The Groundwater Resources Association of California is dedicated to resource management that protects and improves groundwater supply and quality through education and technical leadership. EDITOR Rodney Fricke hydrovisions@grac.org EDITORIAL LAYOUT Smith Moore & Associates EXECUTIVE OFFICERS PRESIDENT Erik Cadaret Yolo County Flood Control & Water Conservation District VICE PRESIDENT Abhishek Singh INTERA SECRETARY Clayton Sorensen West Yost Associates TREASURER Marina Deligiannis Sacramento Area Sewer District DIVERSITY, EQUITY AND INCLUSION OFFICER Annalisa Kihara State Water Resources Control Board IMMEDIATE PAST PRESIDENT Christy Kennedy Woodard & Curran ADMINISTRATIVE DIRECTOR Amanda Rae Smith Groundwater Resources Association of California

DIRECTORS Jena Acos Brownstein Hyatt Farber Schreck Christopher Baker CA DWR Matthew Becker California State University Long Beach Trelawney Bullis AC Foods, Central Valley Dave Ceppos Public Policy Mediation and Facilitaion Elie Haddad Haley & Aldrich Dr. Hiroko Hort GSI Environmental, Inc Len Mason Geosyntec Consultants, Inc. Melissa Turner MLJ Environmental Savannah Tjaden Environmental Science Associates Roohi Toosi APEX Environmental & Water Resources R.T. Van Valer Retired

ISSN 2837-5696

To contact any GRA Officer or Director by email, go to www.grac.org/board-of-directors

The statements and opinions expressed in GRA’s HydroVisions and other publications are those of the authors and/or contributors, and are not necessarily those of the GRA, its Board of Directors, or its members. Further, GRA makes no claims, promises, or guarantees about the absolute accuracy, completeness, or adequacy of the contents of this publication and expressly disclaims liability for errors and omissions in the contents. No warranty of any kind, implied or expressed, or statutory, is given with respect to the contents of this publication or its references to other resources. Reference in this publication to any specific commercial products, processes, or services, or the use of any trade, firm, or corporation name is for the information and convenience of the public, and does not constitute endorsement, recommendation, or favoring by the GRA, its Board of Directors, or its members.

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2026 Fall Issue

Hydro ydro Visions isions

Hydro Visions

Official Publication of the Groundwater Resources Association

6 Seawater Intrusion in

Contents President’s Message

Page 4

Seawater Intrusion in CA

Page 6

Water Quality Under SGMA

Page 10

Water Reliability Depends

Page 16

Tomorrow’s Water Today

Page 20

GeoH2OMysteryPix

Page 26

Parting Shot

Page 28

California Coastal Aquifers

10 Water Quality Under ISSN 2837-5696

SGMA: From Compliance to Sustainable Groundwater Stewardship

16 Water Reliability Depends on More Than Water Supply

Hydro ydro Visions isions

2026 Fall Issue

President’s Message

It’s Fall! Dear GRA Members and Groundwater Super Fans! It’s fall! Sweaters are back, the light is doing that golden thing, and I’m still riding the high from a year of GRA events that felt… different. Elevated. More connected. The kind of rooms (and Zoom squares) you leave thinking, “okay, I want more of that.” If you were in any of them, you already know. If you weren’t, pull up a chair. First up is Groundwater 101 Week. This virtual week has quietly grown into a major success, and we now average over 175 attendees each year. That’s not a one-off. That’s people coming back because the content is useful on Monday morning. Over the course of the week, attendees got a practical sweep of the work we actually do: groundwater quality, well design, aquifer testing, groundwater modeling, geophysics, PFAS, contaminant characterization and remediation, risk assessment, technical writing and presenting, and early-career tips for folks finding their footing in the industry. New this year, a student career session gave the next wave a clearer look at what employers are actually looking for. Thank you, Kate Richards (WSP), and the whole team. You took something GRA has offered for years and turned it into a program people plan around. That is no small thing. Then there’s Flowchella! The 9th Western Groundwater Congress is growing too, and we now average over 400 attendees each year, sponsors and exhibitors included. This year’s theme, Every Drop Deserves a Stage, leaned into stewardship with a desert music-festival energy that fit the place and the moment. Four tracks asked the questions that actually matter: how the system works and how confident we are in what we know; how we design, build, and operate solutions; how we protect and restore groundwater quality while managing quantity; and how we decide, allocate, and implement together. I was blown away by the quality of the presentations and panels. At times, I felt real FOMO. I caught myself thinking I have some catching up to do on topics I thought I already knew! The feedback I heard, over and over, was the same: people felt like part of a community they want to keep engaging with. That is the whole point. Special thank you to Moises Santillan (IEUA), Mesut Cayar (Woodard & Curran), and Hiroko Hort (GSI Environmental), and the whole planning team. It paid off. Zooming out, 2026 as a whole has drawn overwhelmingly positive feedback. People are noticing that our events feel different. They are elevated. They foster community. They bring more value. That is not an accident, and it lines up closely with where our 2026–2028 strategic plan is pointing us: treat our strongest programming as the front door to membership, build a more collaborative groundwater community, and grow from a foundation that volunteers and staff can actually sustain. We are not done. We are building the base to grow from. I'm energized by what this year already showed us. What about you? Are you feeling energized?! We would love to see you get involved in GRA. How can you contribute? Share your ideas and feedback—let's co-create GRA's future. Together, we'll guide the groundwater community toward a more innovative, resilient era that delivers lasting value to our diverse communities!

Erik Cadaret President, Groundwater Resources Association

2026 Fall Issue

President’s Message

Hydro Visions

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Made in the2026USA Fall Issue 5

Hydro Vis Seawater Intrusion in California Coastal Aquifers by Kyle Young, PhD, Hanni Blair, Rick Cramer, PG, Raghavendra Suribhatla Maruti, PhD, PE, and Patrick Wickham PG, CHg Coastal aquifers sustain critical freshwater resources for California’s communities and economies, from public water supplies to irrigation water to support productive agricultural regions where marine-moderated climates support long growing seasons. While these aquifers benefit from their proximity to the coastal mountains (runoff and recharge), this location also makes them inherently vulnerable to seawater intrusion. A relatively small increase in groundwater salinity can compromise drinking water and irrigation uses. Intrusion of just 3% seawater by volume into a fresh groundwater aquifer will exceed California’s upper limit of 1,000 milligrams per liter total dissolved solids for drinking water, potentially driving costly water treatment and presenting limitations for irrigation. Because even the dilute leading edge of this zone can affect drinking water and irrigation uses, understanding the location and dynamics of the freshwater-saltwater interface (“SWI interface”) is critical to protecting fresh coastal groundwater resources. In this article, we present simple analytical methods to provide first-order estimates of the location and depth of the SWI interface. These methods help screen seawater intrusion risk before advancing to more detailed field investigations or numerical modeling.

Figure 1: Conceptual diagram of the SWI interface and relevant geometric variables.

The first method is the well-known Ghyben-Herzberg (GH) relationship (Equation 1) (example units are provided in square brackets):

(1) where: d = depth of the SWI interface below mean sea level, [ft MSL] h = elevation of the GW table above mean sea level, [ft MSL]

Estimating the SWI Interface – Back-of-the-Envelope Analytical Methods

pf = fresh groundwater density, [≈1000 kg/m3 at 0 mg/L salinity]

Several analytical methods are available to approximate the position of the SWI interface (Fetter, 2001). These methods are useful for screening-level evaluations, conceptual model development, and communication. The primary simplifying assumptions for these methods include: homogeneity, isotropy, and simplified aquifer and flow geometries (Panthi et al., 2022). The geometric variables relevant to the three analytical methods we present are referenced in Figure 1.

ps = saline groundwater density, [≈1026 kg/m3 at 35,000 mg/L salinity]

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Hydro Visions

sions The G-H relationship is derived from energy conservation, wherein the SWI interface is conceived to exist at equal pressure as any seaward point at the equipotential height. This approximation invokes several assumptions, including: (1) SWI interface that meets the groundwater table at the tidal zone; (2) vertical equipotential lines; (3) homogenous, unconfined coastal aquifer. While the G-H relationship provides the simplest method for estimating the SWI interface, it provides only a 1-D solution (depth) and requires observation(s) of the groundwater elevation at the desired distance inland from the coast, x. The Dupuit-G-H model (Equations 1 & 2), however, incorporates the G-H relationship with the equation for unconfined flow to resolve the SWI interface depth at any x-location, provided that the shoreline-normalized coastal flow, q, is known or can be estimated:

(2) where: x = inland distance from the shoreline at mean sea level to the point of SWI interface quantification, [ft] q = volumetric groundwater discharge at the coast, per unit length of coastline, [ft3/d/ft] K = hydraulic conductivity of the coastal aquifer, [ft/d] Lastly, the Glover model modifies the Dupuit-G-H model to allow for a coastal groundwater seepage face, eliminating both assumptions (1) and (2) and providing an improved location/ depth solution for the SWI interface as:

Real World Applications of Analytical Estimates A practical application of the G-H relationship can be found in the early development of the West Coast Basin Barrier, one of the largest seawater intrusion mitigation projects in California. During the Manhattan Beach pilot study, engineers used the G-H pressure-balance equation (Equation 1) to determine the minimum freshwater head required to prevent seawater intrusion. Using measured specific gravities of 1.027 for seawater and 1.002 for recharge water, together with an aquifer depth of approximately 110 ft below sea level, they calculated that groundwater levels between recharge wells needed to be maintained at about 2.7 ft above sea level to balance seawater pressure at the base of the aquifer. This target hydraulic head became the design criterion for the recharge barrier (California Department of Water Resources, 1955). Initial analytical estimates based on the Dupuit-G-H and Glover formulations predicted that 3 cfs of recharge was required to maintain the target head along a 4,000-ft reach of coastline; however, pilot testing indicated a larger recharge rate of 4.5 cfs was needed. The difference was attributed to an increase in hydraulic gradient during recharge associated with inland aquifer storage effects, upward leakage through confining layers, and lateral spreading beyond the assumptions of the one-dimensional analytical model. To account for these effects, the investigators introduced an empirical correction term in their analytical methods to represent the rechargeinduced increase in hydraulic gradient, bringing the analytical estimate into agreement with field observations (California Department of Water Resources, 1955). The project's evolution illustrates the role of back-of-the-envelope analytical methods as a starting point that can be refined through field data and iteration.

(3) article continues on next page

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2026 Fall Issue

The “Homogeneous Aquifer” Assumption: The assumption of a homogeneous coastal groundwater aquifer – employed for all analytical SWI interface equations (1, 2, and 3) – is highly idealized. In truth, coastal groundwater flows often exhibit significant spatial variability due to heterogeneities in the coastal aquifer as well as the benthic sediments (Young & Pradhanang, 2021). And, because the SWI interface is a function of the coastal groundwater flow, its location/ depth exhibits similar (though subdued) spatial variabilities. Consequently, employing an average coastal groundwater discharge, q, in Equations (2) and (3) can underestimate the SWI interface depth for areas exhibiting significant coastal groundwater flows, and can overestimate the SWI interface depth for areas without appreciable coastal groundwater flows. Accordingly, zones that exhibit larger coastal groundwater flows can be protective of seawater intrusion, providing a natural barrier against seawater intrusion. However, the converse is also true – if the hydraulic gradient is reduced and flow direction reversed, such as during times of excess pumping, these same locations can behave as preferential seawater intrusion contamination pathways to the aquifer. Practitioners should exercise caution and are advised to explore plausible upper and lower flow values, using these back-of-the-envelope analyses, to account for uncertainties and SWI interface “spreading” factors due to diffusion, longitudinal dispersion, periodic forcings (e.g. pumping, tides, etc.), and aquifer heterogeneities.

Aquifer Heterogeneities and Numerical Modeling of Seawater Intrusion As the subsurface geology is the static framework that is a principal control on groundwater flow, properly addressing seawater intrusion requires a clear understanding of the hydrostratigraphic framework from which groundwater samples are being collected and to better define the aquifer architecture and groundwater basin characterization. A robust geologic model is therefore a prerequisite to define the hydrostratigraphic unit being sampled. Figure 2 depicts the subsurface geologic framework in the LA Basin from the Whittier Narrows to Long Beach, just north of the Dominguez Gap seawater intrusion barrier project, and shows that groundwaters from a “single” aquifer unit – the Silverado Aquifer – can actually derive from one or more of a series of separate, structurally dipping, hydrostratigraphic units (Ehman & Edwards, 2017). The preceding analytical methods are valuable tools for conducting first-order estimations of the SWI interface and resultant seawater intrusion risk to coastal aquifers. However, more robust methods are often required to understand the impact of subsurface heterogeneities and variable groundwater conditions on flow dynamics and seawater intrusion risk. Numerical modeling can help close this gap, providing a means to test coastal demand and climate scenarios and resultant seawater intrusion outcomes for heterogeneous subsurface environments.

Figure 2: A-A' cross section of seismic profiles from Whittier Narrows-1 to the Silverado type well. In orange is the Silverado Aquifer as defined in DWR Bulletin 104 (California Department of Water Resources, 1961) and in yellow is the type well Silverado unit mapped out based on the seismic data. This indicates that multiple hydrostratigraphic units intersect the “Silverado Aquifer”. Figure revised from Ehman & Edwards (2017).

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Hydro Visions

References California Department of Water Resources. (1955). Sea-Water Intrusion in California, Bulletin No. 63. Report prepared by the Los Angeles County Flood Control District. Division of Resources Planning: Sacramento, CA, USA. California Department of Water Resources. (1961). Planned Utilization of the Ground Water Basins of the Coastal Plain of Los Angeles County, Appendix A: Ground Water Geology. Bulletin 104, Appendix A, California Department of Water Resources, Sacramento, California. Ehman, K. D., & Edwards, B. D. (2017). Defining aquifer architecture using seismic and sequence stratigraphy in the Los Angeles Basin, California: A foundation for future assessment and management of groundwater resources. Search and Discovery, Article #80599. https://www.searchanddiscovery.com/ documents/2017/80599ehman/ndx_ehman.pdf Fetter, C.W. (2001). Applied Hydrogeology (4th ed.). Prentice-Hall, Inc.: Upper Saddle River, NJ, USA, 2001. Panthi, J., Pradhanang, S. M., Nolte, A., & Boving, T. B. (2022). Saltwater intrusion into coastal aquifers in the contiguous United States: A systematic review of investigation approaches and monitoring networks. Science of the Total Environment, 836, 155641. https://doi.org/10.1016/j.scitotenv.2022.155641 Young, K. S. R., & Pradhanang, S. M. (2021). Small unmanned aircraft (sUAS)-deployed thermal infrared (TIR) imaging for environmental surveys with implications in submarine groundwater discharge (SGD): Methods, Challenges, and Novel Opportunities. Remote Sensing, 13(7), 1331. doi:10.3390/rs13071331

Hydro Visions

2026 Fall Issue

Hydro Vis Water Quality Under SGMA: From Compliance to Sustainable Groundwater Stewardship by Trey Driscoll and Gus Tolley More than a decade after the passage of California’s Sustainable Groundwater Management Act (SGMA), compliance efforts have been evolving during implementation of the numerous Groundwater Sustainability Plans (GSP). Early implementation centered on groundwater levels, storage depletion, and subsidence; today, attention is increasingly shifting to groundwater quality — a more complex and often less perceivable sustainability indicator. SGMA identifies six undesirable results that groundwater sustainability agencies (GSAs) must avoid, including “significant and unreasonable degraded water quality.” Water quality is influenced by a wide range of natural and humancaused (anthropogenic) factors that may have developed over decades, often without comprehensive monitoring at the scale required to evaluate complex interactions and sources. This complexity has made groundwater quality challenging aspects of SGMA implementation. As GSAs throughout California update and refine their GSPs, water quality has become a critical issue that requires alignment of regulatory compliance, scientific understanding, and practical groundwater management. Figure 1 illustrates the adaptive management process for groundwater stewardship under SGMA. The Unique Challenge of Groundwater Quality Water quality reflects the interaction of hydrology, land use, agricultural practices, geology, well construction, and groundwater management over long periods of time. Sources of impacts are generally categorized two different ways: naturally occurring vs anthropogenic, and point source (specific, identifiable location) vs non-point source (diffuse and arises across a broad area). Most naturally occurring constituents of concern (COCs), such as arsenic, uranium, boron, and salinity, 10

2026 Fall Issue

happen from non-point sources since they are derived from the geologic materials that make up the aquifer. These COCs have been documented by multiple monitoring programs and in GSP basin setting descriptions. Anthropogenic impacts to water quality can come from both point sources and non-point sources. Generally, industrial chemicals, such as chlorinated solvents and petroleum hydrocarbons, are introduced via point sources, whereas agricultural chemicals, such as nitrate, pesticides, and herbicides, come from non-point sources. In most cases, water quality impacts within a groundwater basin predate SGMA and are not likely directly attributable to current groundwater management activities. Recognizing this reality, SGMA does not require GSAs to solve every groundwater quality problem within a basin. Rather, the regulations focuses on preventing groundwater management actions from causing new impacts or exacerbating existing ones. This distinction has become increasingly important as the Department of Water Resources (DWR) and the State Water Resources Control Board (SWRCB) provide guidance and oversight regarding groundwater quality sustainability criteria. Potential water-quality effects should be evaluated before management actions are implemented, particularly where known risk factors are present. Recharge projects may improve water supplies but will change groundwater gradients; and can mobilize COCs and alter contaminant pathways if the COCs are not considered in the design of the projects. Groundwater models and geochemical analyses can inform these evaluations, but many current models will need substantial improvements before they can reliably predict water-quality impacts. Accordingly, available data and tools should first be used to screen projects, with detailed fate-and-transport analysis focused on COCs presenting meaningful potential risk.

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sions Defining “Significant and Unreasonable” One of the most difficult tasks facing GSAs has been developing defensible definitions of significant and unreasonable degraded water quality. Several basins have revised their approaches following DWR reviews and SWRCB evaluations. Recent approaches emphasize that degradation becomes significant and unreasonable when groundwater management activities result in impacts to beneficial uses and users, particularly drinking water supplies and disadvantaged communities. The evolution of these definitions demonstrates a broader trend within SGMA implementation. Early GSPs often focused heavily on monitoring COC concentrations. More recent approaches place greater emphasis on protecting beneficial users and understanding causation. In other words, the critical question is no longer simply whether groundwater quality exceeds a threshold, but whether groundwater management activities caused or contributed to those exceedances and whether they affect groundwater uses. This shift reflects a growing recognition that groundwater quality management must be risk-based, scientifically defensible, and aligned with SGMA’s jurisdictional boundaries and other water quality regulatory programs (https://water. waterboards.ca.gov/water_issues/programs/). The Importance of Monitoring Networks SGMA requires representative monitoring networks that evaluate basin conditions and identify emerging trends. Collecting water-quality samples is only one component of effective monitoring; well-designed sampling must also be paired with an understanding of groundwater flow, hydrogeology, hydroclimatic conditions, and water-level changes in the basin. GSAs utilize water-quality data from federal and state databases, such as the National Water Information System (NWIS), Groundwater Ambient Monitoring and Assessment (GAMA) Program, and Irrigated Lands Regulatory Program (ILRP), and data from public water systems (Safe Drinking Water Information System) and local investigations. These data help establish baseline conditions and characterize

Hydro Visions

natural and human-caused water-quality trends. However, compiling analytical results and well-construction information remains resource-intensive because data are distributed across numerous databases with different well naming conventions, inconsistent data standards, and varying levels of data availability. Costs become even greater when installation of new monitoring wells is required, which can range from tens to hundreds of thousands of dollars depending on the depth, type, and number of monitoring wells required; that doesn’t even include analytical sampling costs. The challenge remains particularly acute in regions with limited historical data as trend analysis requires repeated sampling over many years. Enhancement of monitoring with complete and accurate metadata that fills spatial and temporal gaps should remain an ongoing effort for GSAs. Collecting and analyzing such data and delineating meaningful COCs often requires significant technical analysis and collaboration among local, state, and federal agencies. Protecting Vulnerable Communities Perhaps no aspect of SGMA water quality implementation is more important than protecting drinking water supplies for domestic well users, particularly those in disadvantaged communities. Most rural California residents rely on private domestic wells that are not subject to the same regulatory monitoring requirements as public water systems. These wells may be particularly vulnerable to groundwater quality degradation associated with industrial and agricultural activities, as well as from impacts due to naturally-occurring COCs, as documented in multiple GSPs. Recent SGMA efforts have increasingly incorporated California’s Human Right to Water principles into groundwater quality management frameworks. Some basinwide groundwater quality strategies now explicitly recognize the need to evaluate impacts to domestic well users and severely disadvantaged communities when establishing sustainability criteria. This evolution reflects a broader understanding that groundwater sustainability is ultimately about protecting people as much as aquifers. article continues on next page 2026 Fall Issue

Looking Ahead Groundwater quality remains a closely scrutinized and evolving component of sustainability planning as SGMA implementation advances. The next generation of GSP updates should strengthen monitoring networks, increase sampling frequency, use more sophisticated tools to evaluate how changing hydrologic conditions affect water quality, and refine risk-based decision-making frameworks. Since multiple agencies and entities regulate, manage, and protect groundwater quality, basin-wide partnerships and coordination will be essential to protecting groundwater quality for all beneficial uses.

2026 Fall Issue

Ultimately, SGMA’s success will be measured not only by stabilized groundwater levels and balanced water budgets, but also by whether groundwater remains usable for communities, agriculture, industry, and ecosystems. Water quality management is therefore more than a regulatory obligation; it is an opportunity to build resilient groundwater systems that protect public health, sustain economic vitality, and preserve this critical resource for future generations. Integrating water quality protection into everyday groundwater stewardship may prove to be one of SGMA’s most important and enduring legacies.

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For more information, please contact ou Ehman, K.D., B.D. Edwards, and D.J. Ponti. 2014. Sequence Stratigraphic Framework of Upper Pliocene to Holocene Sediments of the Los Angeles Basin, California: Implications for Aquifer Architecture. Pacific Section, SEPM, Society for Sedimentary Geology. http://pubs.er.usgs.gov/publication/70156831

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2026 Fall Issue Hydro Visions because standard step-out “plume chasing” is not practical given the ubiquitous occurrence, low detection limits, high

mobility, and stringent drinking water standards of these substances. ESS also helps clients understand whether detected

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2026 Fall Issue

Hydro Vis Water Reliability Depends on More Than Water Supply by Robert P. Wichert Groundwater is one of California’s most important water resources, and for many regions, it provides the only reliable source of drinking water. Through regional collaboration and innovative planning, the Sacramento Suburban Water District (SSWD) implemented sustainable groundwater management practices years before the state mandated it under the 2014 Sustainable Groundwater Management Act. This long-term stewardship is especially important because groundwater remains the foundation of SSWD’s water supply. Today, the District operates more than 80 wells throughout our service area. Keeping those wells running reliably requires continual maintenance, repair and, as infrastructure ages, more significant rehabilitation. As with most technical fields, maintaining groundwater infrastructure requires specialized expertise that cannot be easily or quickly replaced. California requires well drilling contractors to have at least four years of experience and pass state licensing examinations. The work itself can include drilling, casing, cementing, cleaning, repairing and rehabilitating wells and their pumping systems. Our state has seen what can happen when demand for those skills increases. During the state’s severe drought a decade ago, the Contractors State License Board expedited licensing for well-drilling and pump contractors to help meet increased demand for their services. The state also encouraged other qualified contractors to pursue welldrilling licenses to help expand capacity. For water agencies, access to this unique expertise matters. When specialized contractors are difficult to secure, routine maintenance can be delayed and unexpected equipment

2026 Fall Issue

failures can leave important water sources offline longer than anticipated. SSWD experienced this challenge firsthand when we became increasingly concerned about our ability to secure specialized well contractors when we needed them. A prolonged outage at one well is manageable. Multiple wells awaiting specialized repairs can begin to affect the flexibility and reliability that water systems depend on. Although often overlooked, access to specialized expertise is a water reliability issue. In 2023, SSWD entered into an exclusive five-year agreement with Kirby’s Pump & Mechanical, a groundwater well contractor, to ensure we had prompt, reliable access to the expertise needed to maintain and repair our wells. Over the following three years, that arrangement gave us an opportunity to see the value of having specialized expertise consistently available when we needed it. It also prompted us to think differently about how we could address our workforce needs over the longer term. This year, that thinking led SSWD to purchase KPM and bring its specialized expertise in-house. It was an unconventional step, and not one that will make sense for every water agency. Before moving forward, our Board commissioned an independent cost-benefit analysis to determine whether the approach made financial and operational sense. The analysis projected that the purchase could pay for itself in less than three and a half years and save approximately $7 million over 10 years. But the larger lesson isn’t about one acquisition. California spends considerable time planning for the physical infrastructure and water supplies we will need in the decades ahead. We should bring that same long-term

Hydro Visions

sions thinking to the people and specialized skills required to operate and maintain those systems. That means asking practical questions. Do we have the expertise needed to maintain critical facilities? Where are we vulnerable to shortages in specialized skills or contractor availability? Could a lack of specialized expertise leave infrastructure unavailable when we need it most? And are there different ways to secure those capabilities before a problem becomes an emergency?

Hydro Visions

The answers will look different for every agency. But for SSWD, bringing a specialized contractor into our workforce ensures a resilient water delivery system backed by the skills needed to keep our infrastructure working long into the future. Robert P. Wichert represents Division 3 on the Sacramento Suburban Water District Board of Directors and is a Citrus Heights resident. Republished from Citrus Heights Sentinel, 29-Sep-26

2026 Fall Issue

Experts from Concept to Operations Comprehensive Solutions for Water Supply Management Æ

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2026 Fall Issue

Hydro Vis Planning For Tomorrow’s Water Today by Dan York, General Manager, Sacramento Suburban Water District Each summer, California’s water supply makes headlines. This year, El Niño is strengthening and federal forecasters say it could become very strong, raising questions about what the coming winter could bring. Reservoir levels fluctuate, drought concerns lead to calls for conservation, and communities wonder what the latest conditions mean for the season ahead. These conversations are important. But they can also obscure a bigger story: reliable water service isn’t built in a single wet year or solved after a single dry one. It’s the result of decisions made years — often decades — before customers ever turn on the tap. This kind of long-term planning matters more than ever. California’s Water Supply Strategy estimates that hotter, drier conditions could reduce the state’s water supply by as much as 10% by 2040. For water providers, adapting means looking beyond today’s conditions and preparing communities for an increasingly variable future. At Sacramento Suburban Water District (SSWD), our Urban Water Management Plan looks at projected demand, available supplies, and reliability through 2050. We evaluate how our water supplies would perform under a range of conditions — not to predict the future, but to identify vulnerabilities and give ourselves time to prepare. The most effective time to address a potential water supply challenge isn’t after it becomes a shortage. It’s before. And the decisions made during wet years are just as important to water reliability as those made during drought.

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Groundwater has long been the foundation of SSWD’s water supply. The District has operated an active conjunctive-use program since 1998, and regional groundwater management efforts predate California’s Sustainable Groundwater Management Act. Conjunctive use may sound technical, but the idea is straightforward: when excess surface water, from rivers, lakes and reservoirs, is available, use it instead of pumping groundwater. This lets the aquifer replenish naturally, building a reserve for dry periods. Long-term water reliability also requires looking beyond jurisdictional boundaries. Groundwater basins, rivers, and water systems must be operated together to maximize water supplies, which requires collaboration among water providers. Across the Sacramento region, agreements like the Water Forum 2050 Agreement and the ARTESIAN Agreement bring water providers together to manage surface water and groundwater as a shared regional resource, supporting reliable supplies, groundwater sustainability and healthy rivers. No forecast can tell us exactly what the Sacramento region will experience this winter, or in the years ahead. Whatever conditions arrive, SSWD has spent years building the flexibility to adapt: protecting its main supply, groundwater, by accessing surface water when available and priced reasonably through partnerships with Placer County Water Agency and the City of Sacramento. Supplementing groundwater with surface water lets us reduce pumping when surface water is available, allowing wells to rest and groundwater reserves to grow, while groundwater itself provides a reserve when conditions turn dry.

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sions Taken together, these decisions leave SSWD well positioned for an uncertain winter and future. But preparedness isn’t a finish line. As conditions become more variable, SSWD and water providers across the region must continue investing in the infrastructure, diverse water supplies and regional coordination that give us flexibility to adapt.

As another summer closes with renewed attention on water conditions, and we look toward a new water year in October, we should certainly ask how our water supplies look today. But we should also ask a more important question: What are we doing today to make sure we have reliable water decades from now?

Customers don’t, and shouldn’t, have to think about everything that makes the water run when they turn on the tap. That’s our job. And doing that job well means continuing to prepare for conditions we may not see for years.

The best time to prepare for the next dry year isn’t when it arrives. It’s before it begins. Republished from Maven’s Notebook, 04-Sep-26

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Hydro Vis GeoH2OMysteryPix by Chris Bonds, GRA, Sacramento Branch Member at Large GeoH2OMysteryPix is a fun addition to HydroVisions that started in Fall 2022. The idea is simple; I provide one or more photograph(s) and two questions, along with a hint, and HydroVisions’ readers email in their guesses. In a future issue of HydroVisions, I will share the answer(s) along with some brief background/historical information about the site photo(s) and acknowledge the first person(s) to email me the correct answer(s). Please note that GeoH2OMysterPix is going on hiatus after this issue. SUMMER 2026 ANSWERS What is this? Where is it Located? Hint: A historically significant place in the foothills of the San Gabriel Mountains. Congratulations to Trevor Pontifex, PG, Hydrogeologist, Montgomery & Associates for providing the following correct response to the Summer 2026 2026 GeoH2OMysteryPix Questions: TP: “That’s the Stone Barn Nature Center at Deukmejian Wilderness Park near Pasadena, where Montgomery & Associates has an office. I hadn’t heard of it before, but I recognized the Verdugo Mountains in the distance. Nowhere else along the San Gabriel Mountains is there another mountain range such a short distance away.” Background/History: The above photo is of the Deukmejian Wilderness Park in La Crescenta-Glendale, CA. Within the park, several significant features are present. The red-roofed structure is the Stone Barn Nature Center which is adjacent to the Dunsmuir Debris Basin and the Dunsmuir Sediment Placement Site. The Stone Barn Nature Center was constructed inside the former Le Mesnager barn, vineyard storage, and residence. The stone barn, constructed mainly of cobbles and boulders from the underlying alluvial fan, is over 100 years old, was built by the Le Mesnager family in the early 1910s, and stored equipment for working the surrounding vineyard. Patriarch George Le Mesnager was a prominent French businessman, winemaker, and a WWI war hero who owned significant land holdings in the Crescenta Valley and operated a land and water company, sourcing spring water from the nearby Dunsmore and Cooks Canyons. The Le Mesnager Family worked the vineyards and land and water company and lived onsite till they sold their land to a developer in the 1960s. After the developer encountered significant development challenges, the land was purchased by the City of Glendale in 1988 who turned the property into the Deukmejian Wilderness Park in 1990. The park was named in honor of George Deukmejian, who provided the critical final monies to purchase the land.

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sions The Dunsmuir Debris Basin and Sediment Placement Site were constructed by the US Army Corps of Engineers following the devastating 1934 New Year’s Day Flood in the Crescenta Valley and surrounding areas. These local flood control facilities, managed by the LA County Department of Public Works, are part of the LA County Flood Control System which captures flood debris, stores sediment, and conveys flood waters to the Verdugo Wash and LA River which empties into the Pacific Ocean near Long Beach.

The Le Mesnager winery and vineyards following the 1934 New Year’s Flood. Glendale Public Library.

The Stone Barn Nature Center and Vineyards. City of Glendale.

References: 2004, Cecilia Rasmussen. Out of Stone, A Vintage History. LA Times Article. 2010. Bonterra Consulting. Initial Study/Mitigated Negative Declaration for Section 1605 Long-Term Streambed Alteration Agreement for the Debris Basin Maintenance Program. LA County Department of Public Works on behalf of the LA County Flood Control District. 2014, Stuart D. Byles. Los Angeles Wine: A History from the Mission Era to the Present. American Palate. Book. 2024, Mike Lawler. The Stone Barn and the Local History of Winemaking. CV Weekly Newspaper Column Article.

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Hydro Visi Parting Shot by John Karachewski, PhD, DTSC PG & CHg - retired

Fern Canyon is a popular and scenic hike to a gorge with fern-covered walls located in Prairie Creek Redwoods State Park in Humboldt County. A day-use reservation is required to visit the Fern Canyon/Gold Bluffs Beach area from May 15th to September 15th due to its popularity.

The Pacific temperate rain forest setting as well as groundwater seeps discharging from the sediments provide ideal conditions for the growth of ferns, mosses, and shrubs. Eight species of ferns are present in the canyon - the most abundant being the five-finger fern.

Home Creek has eroded a 50- to 80-foot deep canyon through the Plio-Pleistocene Prairie Creek Formation. These weakly consolidated sands and gravels reflect a variety of depositional settings, including the mouth of the ancestral Klamath River, nearshore marine, delta, estuarine, and beach environments. Since about 700,000 years ago, the mouth of the Klamath River has shifted approximately 8 miles to the north.

The prehistoric-looking canyon has provided the backdrop for several dinosaur scenes in both documentaries and movies. Steven Spielberg filmed scenes for The Lost World: Jurassic Park (1997) at Fern Canyon, where the character Dieter Stark is attacked by a pack of Compsognathus. Walking with Dinosaurs (1999): The BBC documentary series used the lush, ancient fern covered canyon to recreate prehistoric environments. Dinosaurs Alive! (2007): the IMAX film also utilized the unique scenery.

The dominant source rocks of the Prairie Creek Formation are plutonic and metamorphic rocks from the Klamath Mountains to the east of the park. Uranium–lead ages of individual zircon grains in these sediments also revealed a previously unrecognized provenance—the Idaho batholith. Thus, while the ancestral Klamath River was actively depositing the sands and gravels of the Prairie Creek Formation, other large ancestral rivers were delivering sediments from distant Idaho. This discovery has important implications for interpreting the regional development of river systems of the northwestern United States. The Prairie Creek Formation contains only minor amounts of Franciscan Complex detritus.

Photographed in Fern Canyon by John A. Karachewski, PhD, on September 3, 2026. The approximate GPS coordinates of the photograph are 41.402574° and -124.061357 °. Current conditions and information about visiting this area are available at the Prairie Creek Redwoods State Park website.

Reflecting its origin at the mouth of the ancestral Klamath River, the Prairie Creek Formation has a variety of fossils, including freshwater pelecypods and burrows as well as abundant plant fossils such as leaf impressions, carbonized leaves, cones, and petrified logs.

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Thank You to Our Contributors Hanni Blair is a hydrogeologist specializing in groundwater modeling. She has expertise in variable density flow and transport simulation, seawater intrusion analysis, and groundwater sustainability planning. She has supported groundwater sustainability efforts throughout California, with a particular focus on seawater intrusion mitigation and integrated hydrologic modeling in the Salinas Valley. Chris Bonds is a Senior Engineering Geologist (Specialist) with the California Department of Water Resources (DWR) in Sacramento. Since 2001, he has been involved in a variety of statewide projects including groundwater exploration, management, monitoring, modeling, policy, research, and water transfers. Chris has over 31 years of professional work experience in the private and public sectors in California, Hawaii, and Alaska and is a Professional Geologist and Certified Hydrogeologist. Erik Cadaret is an Associate Geologist with West Yost Associates and joined the GRA Board of Directors in 2021. Erik’s role with West Yost is to support various groundwater technical projects for clients within the state of California, management of a GSA in northern California, and support business development efforts to engage new clients. Erik loves being a part of GRA because it provides an outlet to collaborate with some of the greatest minds in groundwater. Rick Cramer, PG, is a Senior Principal Geologist for Geosyntec Consultants with over 30 years of experience as a consultant in the groundwater industry focusing on applying advanced geologic methods to improve hydrogeologic conceptual site models by defining the subsurface geologic heterogeneity. Trey Driscoll, PG, CHG, is the Managing California Director of Water Resources & Supply for INTERA. We provide stewardship and innovation to state and local water agencies for a sustainable tomorrow focused on water planning, supply development, recharge (ASR and MAR) and decision-support. Trey enjoys collaborating with fellow GRA members to help shape the future of water resources in California.

Gus Tolley, PhD, specializes in groundwater hydrology, numerical modeling, groundwater–surface water interactions, contaminant transport, GIS mapping, and workflow automation, with deep experience in developing, calibrating, and analyzing integrated hydrologic models for agricultural basins. Patrick Wickham PG, CHg, is a hydrogeologist specializing in groundwater management, modeling, and data analysis. His expertise in hydrogeology, water supply planning, and programming allows him to develop novel approaches to complex water resource challenges. He has contributed to groundwater sustainability planning across the western U.S., with a recent focus on the California Coast. Robert P. Wichert is a mechanical engineer, energy consultant, and Division 3 director for Sacramento Suburban Water District, with experience in battery system design, sustainable energy, public utility operations, water affordability, infrastructure planning, and groundwater resource management. Dan York is General Manager of Sacramento Suburban Water District, bringing more than 35 years of public water utility experience in district operations, planning, personnel supervision, and water supply management, along with state certifications in water treatment and distribution. Kyle Young, PhD, is a coastal hydrogeologist with academic experience in groundwater physics, hydrologic processes, and geophysics consulting. His expertise in groundwater physics and coastal hydrogeology derives from extensive training and research quantifying submarine groundwater discharge. Dr. Young has significant experience utilizing hydrologic modeling software and Geographic Information Systems (GIS) to characterize surface water flows for Managed Aquifer Recharge (MAR) decision-making.

John Karachewski, PhD, retired recently from the California-EPA in Berkeley after serving as geologist for many years in the Geological Support Branch of the Permitting & Corrective Action Division for Hazardous Waste Management. He leads numerous geology field trips for the Field Institute and also enjoys teaching at Diablo Valley College. John enjoys photographing landscapes during the magic light of sunrise and sunset. Since 2009, John has written quarterly photo essays for Hydrovisions. Raghavendra Suribhatla Maruti, PhD, PE is a Technical Expert with Haley & Aldrich and a licensed Professional Civil Engineer focused on coastal groundwater management, seawater intrusion control, applied research, and climate resiliency. He serves as the California modeling manager for H&A’s applied research and climate resiliency projects, integrating hydrogeologic interpretation, numerical modeling, and decision support for complex water-resource challenges.

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