Retrofitting Sustainable Urban Drainage Systems (SuDS): A Cost-Benefit Analysis Appraisal

Water (MDPI) | August 16th, 2022

Sustainable Urban Drainage Systems (SuDS) are known to help mitigate flooding whilst simultaneously delivering other positive outcomes, such as the provision of environme

Sustainable Urban Drainage Systems (SuDS) are known to help mitigate flooding whilst simultaneously delivering other positive outcomes, such as the provision of environmental, economic, educational, and business benefits. Despite this, there has been a relatively low uptake of SuDS in new developments and even less of an uptake in the opportunities for retrofitting SuDS in existing buildings. A major barrier to uptake has been a lack of understanding regarding the value of the benefits provided by SuDS. This study presents an appraisal of the costs and benefits derived from the retrofitting of SuDS in existing buildings and reveals some of the key decision-making considerations during the design and installation of such schemes. A qualitative research approach that included a number of case studies of successfully retrofitted SuDS schemes within public buildings was conducted. A novel feature of the research was the use of the Willingness to Pay (WTP) approach to value the tangible and intangible benefits provided by the various schemes from the perspectives of the property owners. The findings revealed that the retrofit provided a net value to the client of over £100,000 over 10 years, a mean CBA ratio of 5.3/10, and a return on investment (ROI) that would be achieved in less than 3 years. The importance of stakeholder engagement during the decision-making process was highlighted in helping to overcome many of the design, installation, and maintenance challenges. The findings demonstrate a significant ROI for these SuDs retrofit schemes and highlight useful approaches to overcoming the barriers in valuing the importance of the intangible benefits. In supporting the uptake of the retrofitting of SuDS, it is recommended that these benefits are given full consideration by property owners, urban planners, and architects during the design of retrofit schemes and throughout the decision-making stage.

Rising Seas and Electricity Infrastructure: Potential Impacts and Adaptation Actions for San Diego Gas & Electric

California Energy Commission (CEC) | August 31st, 2018

Part A: Rising sea levels pose a threat to California’s energy infrastructure and the coastal communities that it serves. To better understand this threat, this

Part A: Rising sea levels pose a threat to California’s energy infrastructure and the coastal communities that it serves. To better understand this threat, this study analyzed the exposure of San Diego Gas & Electric Company (SDG&E) electricity assets in San Diego County to climate change- driven coastal wave flooding, tidal inundation, and coastal erosion. The study found that the greatest potential direct impacts are damage to four substations in the Mission Bay and San Diego Bay areas. By modeling the potential costs to customers from unserved energy due to service disruptions driven by exposed substations, this study found economic impacts could— under an extreme sea level rise scenario in the late 21st century compounded by a 100 year storm-- range from $1.2 billion to $25 billion, assuming no adaptation actions are taken. Nearby communities could also experience indirect impacts if critical customers served by the substations—such as sewage pumping stations, hospitals, airports, and ports—are affected by outages. For other asset types, potential direct impacts are expected in the form of increased maintenance and repair costs. The research team identified a range of potential adaptation measures to build resilience to potential impacts. The application of flexible adaptation pathways emerged through the study as the best approach to improve implementation of these measures in the face of future uncertainty. Rather than selecting adaptation measures based only on what is known today, flexible adaptation pathways help establish information that that should be tracked, termed signposts, to help navigate uncertainty, set thresholds that trigger adaptation actions, and determine if an adaptation plan is meeting its objectives. Using these pathways, four initial climate adaptation actions were identified for SDG&E: 1) enhance coastal storm prediction and response, 2) identify signposts and thresholds that indicate when the need for an adaptation decision is approaching, 3) conduct consultations with regional stakeholders to identify opportunities to improve community-wide resilience, and 4) improve and fine-tune cost-benefit analysis methods to increase accuracy and confidence in cost-benefit estimates that incorporate climate change. Click here for Part B of the report, Potential Climate Change Impacts and Adaptation Actions for Gas Assets in the San Diego Gas and Electric Company Service Area, CEC, 2018

Root Causes Analyses of the Oroville Dam Gated Spillway Failures and Other Developments

University of California, Berkeley (UC Berkeley) | July 20th, 2017

We have performed forensic Root Causes Analyses of the Oroville Dam Gated Spillway failures and other associated developments as unfunded (approximately 3,000 pro-bono h

We have performed forensic Root Causes Analyses of the Oroville Dam Gated Spillway failures and other associated developments as unfunded (approximately 3,000 pro-bono hours) volunteers of the University of California at Berkeley (UCB) Center for Catastrophic Risk Management (CCRM) Oroville Dam Advisory Group (ODAG). We initiated this work on January 27, 2017. The results contained in this report have been developed based on the currently available public document and information sources cited at the end of this report, included in the Preliminary Root Causes Analysis of the Failures of the Oroville Dam Gated Spillway report dated April 17, 2017, and in the Legislative Oversight Report: Oroville Dam report dated May 11, 2017.  This report documents our analyses of the Root Causes of the initial failure of the Gated Spillway. Appendix A of this report provides summaries of the procedures and processes we used to perform the Root Causes analyses, background on the components that comprise Engineered Systems, and background on the Human and Organizational Factor malfunctions (errors) responsible for failures of Engineered Systems. Appendix B provides details of our analyses of the Physical and Organizational Root Causes of the initial failure of the Gated Spillway. The opinions expressed in this Report are ours alone. The opinions expressed herein are a fair and accurate summary of our opinions, based upon our experience, education, training, and expertise.

Ruling on Motions for Preliminary Injunction in Tulare Lake Basin Water Storage District v. California Department of Water Resources

Superior Court of California, County of Sacramento | June 20th, 2024

Running Dry: Weathering the Great California Drought

Harvard University | December 1st, 2016

Essays include: "Physical Mechanisms of the California Drought" - Richard Seager "Droughts and the Global Economy: Lessons from California" - Jay R. Lund

Essays include: "Physical Mechanisms of the California Drought" - Richard Seager "Droughts and the Global Economy: Lessons from California" - Jay R. Lund "Addressing Variability: Adaptation and Innovation in California’s Water Systems" - Laila Kasuri "The California Case: Managing Groundwater in Irrigated Agriculture" - Josué Medellín-Azuara "The Hidden Health Consequences of Drought" - Rory Stewart & Erika Eitland "California’s Unconventional Energy-Water Nexus" - Jonathan Buonocore, Don Kriens, Susan Cahalan, Drew Michanowicz, Alexandra Gast, Kate Konschnik "The 2 R’s: What Brazil Can Teach Us About California’s Drought" -  Luis Augusto Bertoni Strengari "Carlsbad Desalination: A Leap in Water Prices, for the Better?" - Aldís Elfarsdóttir

San Diego Basin Study

U.S. Bureau of Reclamation (USBR) | August 15th, 2017

The purpose of the San Diego Basin Study (Basin Study) is to determine potential climate change impacts on water supplies and demands within the San Diego region and to i

The purpose of the San Diego Basin Study (Basin Study) is to determine potential climate change impacts on water supplies and demands within the San Diego region and to identify how potential adaptation strategies could mitigate supply shortages. The intention of Task 2.3 is to create a computer simulation model to forecast supply and demand imbalances under current and future conditions, and current and future demands under a baseline water system infrastructure in the Study Area. This Interim Report describes the methodologies and findings of this Task. 

San Francisco Bay Shore Inventory: Mapping for Sea Level Rise Planning

San Francisco Estuary Institute (SFEI) | July 1st, 2016

With rising sea levels and the increased likelihood of extreme weather events, it is important for regional agencies and local municipalities in the San Francisco Bay Are

With rising sea levels and the increased likelihood of extreme weather events, it is important for regional agencies and local municipalities in the San Francisco Bay Area to have a clear understanding of the status, composition, condition, and elevation of our current Bay shore, including both natural features and built infrastructure. The purpose of this Bay shore inventory is to create a comprehensive and consistent picture of today’s Bay shore features to inform regional planning. This dataset includes both structures engineered expressly for flood risk management (such as accredited levees) and features that affect flooding at the shore but are not designed or maintained for this purpose (such as berms, road embankments, and marshes). This mapping covers as much of the ‘real world’ influence on flooding and flood routing as possible, including the large number of non-accredited structures. This information is needed to: identify areas vulnerable to flooding. identify adaptation constraints due to present Bay shore alignments; and suggest opportunities where beaches, wetlands, and floodplains can be maintained or restored and integrated into flood risk management strategies. The primary focus of the project is therefore to inform regional planners and managers of Bay shore characteristics and vulnerabilities. The mapping presented here is neither to inform FEMA flood designation nor is it a replacement for site-specific analysis and design. The mapping consists of two main elements: Mapping of Bay shore features (levees, berms, roads, railroads, embankments, etc.) which could affect flooding and flood routing. Attributing Bay shore features with additional information including elevations, armoring, ownership (when known), among others. SFEI delineated and characterized the Bay shore inland to 3 meters (10ft) above mean higher high water (MHHW) to accommodate observed extreme water levels and the commonly used range of future sea level rise (SLR) scenarios. Elevated Bay shore features were mapped and classified as engineered levees, berms, embankments, transportation structures, wetlands, natural shoreline, channel openings, or water control structures. Mapped features were also attributed with elevation (vertical accuracy of <5cm reported in 30 meter (100ft) segments from LiDAR derived digital elevation models (DEMs), FEMA accreditation status, fortification (e.g., riprap, buttressing), frontage (e.g., whether a feature was fronted by a wetland or beach), ownership, and entity responsible for maintenance. Water control structures, ownership, and maintenance attributes were captured where data was available (not complete for entire dataset). The dataset was extensively reviewed and corrected by city, county, and natural resource agency staff in each county around the Bay. This report provides further description of the Bay shore inventory and methods used for developing the dataset. The result is a publicly accessible GIS spatial database.

San Francisco Water & Power: A History of the Municipal Water Department and Hetch Hetchy System

San Francisco Public Utilities Commission (SFPUC) | January 1st, 1985

Santa Ana Canal

Scientific American | March 10th, 1900

THE area discussed in this report is in Southern California, lying for the most part easterly from the city of San Bernardino and consisting of the upper or higher par

THE area discussed in this report is in Southern California, lying for the most part easterly from the city of San Bernardino and consisting of the upper or higher part of the valley in which is situated the town of Redlands. It is a bout 50 miles distant from the ocean and has an elevation of from 1,000 to 1, 500 feet in the vicinity of San Bernardino and Redlands. Northerly and easterly from the valley the mountains rise abruptly, reaching altitudes of fro m 6,000 to 7,000 feet, a few of the peaks rising to 10,000 or even 11,000 feet. The abrupt slopes by which the valley is bounded aid in producing a rainfall relatively heavy for the arid region. The waters, uniting into streams, descend rapidly through narrow gorges, issuing finally upon accumulations of bowlders and smaller debris which stretch in fan-shaped masses away from the mouth of each canyon. The region, though dry, has thus a notable water supply and the exceptional climate and soil have resulted in an extraordinary development of agriculture by irrigation. Lands and crops have reached high values in San Bernardino Valley and expensive irrigation works have been built. A denser population is supported than in any other farming region of the West. This has been accomplished in spite of the fact that the cost of constructing works and of reclaiming the lands has been very great. Additional resources on Lippincott: J.B. Lippincott Papers, University of California, Riverside The Santa Ana River: How it Shaped Orange County

Scaling protection and restoration of natural infrastructure to reduce flood impacts and enhance resilience

Shore & Beach (American Shore and Beach Preservation Association) | January 10th, 2020

Restoring natural infrastructure offers much promise as a means to reduce both flood hazard and exposure to complement and supplement other flood damage reduction strat

Restoring natural infrastructure offers much promise as a means to reduce both flood hazard and exposure to complement and supplement other flood damage reduction strategies. Interest increased in flood risk reduction methods using natural and nature-based features, in part, because of increased recognition that such could provide both flood risk reduction and other benefits, such as water quality uplift, community recreational space, and fish and wildlife habitat. Recent flood disasters and the rising costs of disaster response and recovery have triggered policy shifts toward economically efficient investments that enhance greater community resilience. While natural infrastructure is becoming more widely recognized as a tactic for building community and ecological resilience to erosion and flooding, it remains underutilized. Actions to aid consideration of natural infrastructure and scale up its use are presented.