Toward Natural Infrastructure to Manage Shoreline Change in California

California Natural Resources Agency (CNRA) | August 27th, 2018

Flooding and erosion caused by rising sea levels and powerful storms threaten property throughout coastal California. To protect against these climate-change related thr

Flooding and erosion caused by rising sea levels and powerful storms threaten property throughout coastal California. To protect against these climate-change related threats, landowners will certainly take action, and the default industry standard response has been to try to “hold the line” against the encroaching sea by constructing seawalls, dikes, levees and other forms of coastal armoring. While armoring may in some cases provide acceptable short-term protection, armoring also tends to accelerate shoreline erosion, exacerbating hazards to people and leading to the eventual loss of critical wildlife habitat and public beaches. Natural Shoreline Infrastructure can be as effective as armoring, while having the added benefits of preserving coastal habitat and public access. Recognizing this, California agencies have mandated that decision-makers prioritize its use in planning and investment decisions. Yet, planners have encountered many stumbling blocks as they have tried to incorporate these approaches into coastal resilience plans. Major obstacles include: a lack of a common definition and shared terminology; lack of expertise; lack of precedent; and the absence of siting guidance and technical design standards. Here, we set out to enable planners to adopt Natural Shoreline Infrastructure by filling in the missing information. With the input of dozens of coastal managers who served on our Technical Advisory Committee, we developed a definition and collected a list of case studies where Natural Shoreline Infrastructure has already been successfully deployed in California. Drawing from these and other projects, we collected into one place the first detailed technical guidance for implementation, including siting criteria and design thresholds. These criteria inform decisions about where and when to use six types of Natural Shoreline Infrastructure (e.g. sand dunes, seagrass beds). Using Monterey Bay and Ventura County projects as examples, we demonstrate how to use the technical guidance in tandem with spatial data to match a particular shoreline environment with appropriate Natural Shoreline Infrastructure options, creating “blueprints” for action. The information in this report is intended to facilitate the use of Natural Shoreline Infrastructure along California’s coast, improving the resilience of communities and habitats in the face of climate change.

Towards an operational anthropogenic CO2 emissions monitoring and verification support capacity

American Meteorological Society (AMS) | February 10th, 2020

Under the Paris Agreement progress of emission reduction efforts is tracked on the basis of regular updates to national Greenhouse Gas (GHG) inventories, referred to as

Under the Paris Agreement progress of emission reduction efforts is tracked on the basis of regular updates to national Greenhouse Gas (GHG) inventories, referred to as bottom-up estimates. However, only top-down atmospheric measurements can provide observation-based evidence of emission trends. Today there is no internationally agreed, operational capacity to monitor anthropogenic GHG emission trends using atmospheric measurements to complement national bottom-up inventories. The European Commission (EC), the European Space Agency, the European Centre for Medium-Range Weather Forecasts, the European Organisation for the Exploitation of Meteorological Satellites and international experts, are joining forces to develop such an operational capacity for monitoring anthropogenic CO2 emissions as a new CO2 service under EC's Copernicus Programme. Design studies have been used to translate identified needs into defined requirements and functionalities of this anthropogenic CO2 emissions Monitoring and Verification Support (CO2MVS) capacity. It adopts a holistic view and includes components such as atmospheric space-borne and in-situ measurements, bottom up CO2 emission maps, improved modeling of the carbon cycle, an operational data assimilation system integrating top-down and bottom-up information, and a policy-relevant decision support tool. The CO2MVS capacity with operational capabilities by 2026, is expected to visualize regular updates of global CO2 emissions, likely at 0.05°x0.05°. This will complement the PA’s enhanced transparency framework, providing actionable information on anthropogenic CO2 emissions that are the main driver of climate change. This information will be available to all stakeholders, including governments and citizens, allowing them to reflect on trends and effectiveness of reduction measures. The new EC gave green light to pass the CO2MVS from exploratory to implementing phase.

Towards sharing water better with near real-time maps on evaporative water use by crops and natural vegetation

Nature Portfolio (Springer Nature) | January 15th, 2024

The combination of advancements in evapotranspiration theory, eddy covariance flux measurements of water vapour and satellite remote sensing are putting technology on the

The combination of advancements in evapotranspiration theory, eddy covariance flux measurements of water vapour and satellite remote sensing are putting technology on the verge of producing information on evapotranspiration with unprecedented coverage and resolution. The OpenET project provides this information to farmers and land and water managers for better water practice.

Towards the Protection, Restoration, and Enhancement of the Delta Ecosystem: A Synthesis

Delta Stewardship Council (Delta Council) | March 15th, 2018

Towards the Protection, Restoration, and Enhancement of the Delta Ecosystem: A Synthesis. Appendix A: Summary of Existing Habitat and Species-Specific Plans, Strategies, and Management Approaches

Delta Stewardship Council (Delta Council) | March 15th, 2018

Toxicological assessment of potable reuse and conventional drinking waters

Nature Portfolio (Springer Nature) | October 27th, 2022

Potable reuse, the process of treating wastewater to drinkable standards, offers a reliable and sustainable solution to cities and regions facing shortages of clean water

Potable reuse, the process of treating wastewater to drinkable standards, offers a reliable and sustainable solution to cities and regions facing shortages of clean water. However, implementation is hindered by perceptions of poor water quality and potential health threats. Herein, we compare water samples from potable reuse systems with conventional drinking waters based on the analysis of Chinese hamster ovary cell cytotoxicity contributed by disinfection by-products (DBPs) and sewage-derived anthropogenic contaminants. In all cases, the cytotoxicity of potable reuse waters is lower than that of drinking waters derived from surface waters. The median contribution to total cytotoxicity was 0.2% for regulated DBPs and 16% for the unregulated DBPs of current research interest. Nonvolatile, uncharacterized DBPs and anthropogenic contaminants accounted for 83% of total cytotoxicity. Potable reuse waters treated by reverse osmosis are not more cytotoxic than groundwaters. Even in the absence of reverse osmosis, reuse waters are less cytotoxic than surface drinking waters. Our results suggest that potable reuse can provide a safe, energy-efficient and cost-effective alternative water supply.

Tracing enhanced oil recovery signatures in casing gases from the Lost Hills oil field using noble gases

Earth and Planetary Science Letters (Elsevier) | August 15th, 2018

Enhanced oil recovery (EOR) and hydraulic fracturing practices are commonly used methods to improve hydrocarbon extraction efficiency; however, the environmental effects

Enhanced oil recovery (EOR) and hydraulic fracturing practices are commonly used methods to improve hydrocarbon extraction efficiency; however, the environmental effects of such practices remain poorly understood. EOR is particularly prevalent in oil fields throughout California where water resources are in high demand and the disposal of large volumes of produced water may affect groundwater quality. Consequently, it is essential to better understand the fate of injected (EOR) fluids in California, and other subsurface petroleum systems, as well as any potential effect on nearby aquifer systems. Noble gases can be used as tracers to understand hydrocarbon generation, migration, and storage conditions, as well as the relative proportions of oil and water present in the subsurface. In addition, a noble gas signature diagnostic of injected (EOR) fluids can be readily identified. We report noble gas isotope and concentration data in casing gases from oil production wells in the Lost Hills oil field, northwest of Bakersfield, California, and injectate gas data from the Fruitvale oil field, located within the city of Bakersfield. Casing and injectate gas data are used to: 1) establish pristine hydrocarbon noble-gas signatures and the processes controlling noble gas distributions, 2) characterize the noble gas signature of injectate fluids, 3) trace injectate fluids in the subsurface, and 4) construct a model to estimate EOR efficiency. Noble gas results range from pristine to significantly modified by EOR, and can be best explained using a solubility exchange model between oil and connate/formation fluids, followed by gas exsolution upon production. This model is sensitive to oil–water interaction during hydrocarbon expulsion, migration, and storage at reservoir conditions, as well as any subsequent modification by EOR.

Tracking California’s sinking coast from space: Implications for relative sea-level rise

American Association for the Advancement of Science (AAAS) | July 31st, 2020

Coastal vertical land motion affects projections of sea-level rise, and subsidence exacerbates flooding hazards. Along the ~1350-km California coastline, record

Coastal vertical land motion affects projections of sea-level rise, and subsidence exacerbates flooding hazards. Along the ~1350-km California coastline, records of high-resolution vertical land motion rates are scarce due to sparse instrumentation, and hazards to coastal communities are underestimated. Here, we considered a ~100-km-wide swath of land along California’s coast and performed a multitemporal interferometric synthetic aperture radar (InSAR) analysis of large datasets, obtaining estimates of vertical land motion rates for California’s entire coast at ~100-m dimensions—a ~1000-fold resolution improvement to the previous record. We estimate between 4.3 million and 8.7 million people in California’s coastal communities, including 460,000 to 805,000 in San Francisco, 8000 to 2,300,00 in Los Angeles, and 2,000,000 to 2,300,000 in San Diego, are exposed to subsidence. The unprecedented detail and submillimeter accuracy resolved in our vertical land motion dataset can transform the analysis of natural and anthropogenic changes in relative sea-level and associated hazards.

Tracking California’s striking water storage gains attributed to intensive atmospheric rivers

Journal of Hydrology (Elsevier) | February 5th, 2025

California is highly vulnerable to extreme precipitation events due to the dense landfall of atmospheric rivers (ARs) during the winter months, often resulting in catastr

California is highly vulnerable to extreme precipitation events due to the dense landfall of atmospheric rivers (ARs) during the winter months, often resulting in catastrophic consequences such as widespread floods, mudslides, and landslides. This study focuses on the recovery of daily variations in AR-driven terrestrial water storage (TWS), which produces geodetically detectable ground subsidence. We invert GNSS vertical positions to obtain daily estimates of equivalent water height (EWH) through a variational Bayesian principal component analysis (vbPCA) based inversion scheme and track significant water gains during record-setting winter months in four water years (WYs) 2011, 2017, 2019, and 2023. These precipitation extremes have resulted in a substantial short-term increase in water storage, as evidenced by the multi-source EWH datasets (GNSS, GRACE, and NLDAS). Notably, WY 2023 experienced the highest snowfall due to the landfalls of high-density, high-category ARs, while WY 2017 recorded the highest precipitation totals, driven by the most frequent occurrence of hazardous ARs. Our findings further highlight that GNSS can accurately detect exceptionally wet hydrological events on short time scales, benefiting from an improved signal-to-noise ratio due to substantial increase in water storage. The results also indicate that while these extreme water years can help alleviate surface subsidence in the Central Valley caused by groundwater overexploitation, it is insufficient to alter California’s heavy reliance on groundwater for its intensive agricultural activities. Our findings demonstrate that GNSS is successful in tracking prodigious water increases from short-term precipitation extremes that are weaker than powerful hurricanes, illuminating the prospect of GNSS in supporting water management and flood preparedness.

Tracking Organic Matter in Delta Drinking Water

CALFED | April 1st, 2008