By Jay Lund
California’s ongoing floods and very wet year overall will continue to grab headlines, provide great pictures, and break some local records, but overall this year is unlikely to be truly extreme from historical or broader water policy and management perspectives. It can still be a very useful wet year, beyond just having lots of water.
Wet year water statistics and record-breaking
Today’s essay reflects on our obsession to identify unique aspects of flooding in California this year. Were floods on the Cosumnes, Russian, Salinas, and other rivers “record-breaking”? Is the ongoing and coming flooding in the Tulare Basin “record-breaking”? (DWR 2023; Moyle 2023)
In most cases no, even though 2023 is a very wet year for most of California, and naturally invites search for such comparisons. California has over 100 years of fairly good flood and water records – for any given year to be record-breaking probably requires some teasing of data.
Because any major hydrologic event is complex, it is not especially hard to find some way that any sizable high or low flow event is “record-breaking.” “Record-breaking” could be in terms of any aspect of magnitude, duration, number of peaks, rapidity of water’s rise or fall, the duration of flow above some threshold, repetition frequency, temperature, rate of change in temperature, etc., etc. (Just as every human is unique, we are normal in most regards. And good social policies must reflect both our uniqueness and banality.)
Identifying new extremes serves various interests, agencies, and advocates by bringing attention, funding, and legislation to their issues. In the complex governance of water in California, a little panic can be essential for mobilizing diverse units of government and elected leaders toward individual action and seems especially important for forging collective action (Pinter et al. 2019).
In a land of common (if not routine) hydrologic extremes, the search for “record-breaking” events is easy, attractive to both water professionals and the curious public, and is often irrelevant and distracting for management, policy, and the public interest.
Our obsessions with record-breaking aspects of recent flooding will be rewarded with interesting stories from the many basins and locations affected, their interesting histories, and how these events differ from those in the past. Among the hundreds of basins and thousands of locations and miles of levees, it would be incredible if a set of major storms did not create such stories, including quite a few real human and social tragedies.
Banality of Effective Flood Management
Even the unusual major flooding in the Tulare Lake basin is not a lot of water for the Tulare basin (which has the most human water use of any hydrologic region in California, about 9 million acre-feet/year). The major flooding issue is that the Tulare Lake basin has no direct outlet to the sea, so flood water collects in the old Tulare Lake bed and similar nearby dead-end lakes (such as Buena Vista Lake), until they individually or collectively overflow into the San Joaquin River (a rare event), evaporate, seep to groundwater, or are pumped for crop irrigation (Arax and Wartzman 2005).
For a basin with an average natural streamflow of about 3.3 million acre-ft/year and an average annual groundwater overdraft of about 2 million acre-feet, having 2-3 million acre-feet of flood waters collecting in the Tulare Lake bed this year is about one year of average basin overdraft and not even half of the annual 6 million acre-ft of groundwater overdraft seen in recent drought years (Lund et al. 2018). Capturing flood waters can be useful, but will never be nearly enough to make up this region’s long-term deficits.
These interesting and important stories stand in contrast to the relative effectiveness of California’s rather fragmented flood management system, despite its gaps, lacks, and imperfections in organization, funding, and implementations of state, federal, and local flood plans. California has major floods, with relatively little major flooding, and even fewer major deaths, economic losses, and flood insurance claims (at least so far this year). The effectiveness of flood predictions, warnings, evacuations, and infrastructure, while never perfect and always in need of improvement, largely do the system and the people of California proud.
Overall, the non-record-breaking floods this year offer important reminders that:
- California has floods (as well as droughts).
- California’s localities and regions, as well as state and federal governments, need to organize, prepare, and invest for floods.
- Local agencies are the most important part of flood management in most of California. Most flood preparations, warnings, and evacuations are organized by local agencies. Most deaths and damage this year resulted from local and private decisions – ranging from local levee maintenance and land use decisions to personal driving behavior into moving flood waters.
- Flood waters come at times and places where capturing it is often (but not always) expensive, inconvenient, or even dangerous to collect, so we will never be able or willing to capture most of it.
- Flood forecasting, warning, and evacuation systems remain fundamental for reducing flood deaths and damages in California. This system of forecasts, warnings, and evacuations is a wonderful orchestra of national, state, regional, and local agencies – galvanized by a common knowledge that a major flood can occur anywhere in California in any year (even a nominal drought year).
- With many thousands of miles of local and system levees managed by hundreds of local flood agencies and organizations with only tentative funding, we should expect more problems than we actually have seen (and presumably we can expect to see more problems with a warming and more variable climate).
We should place our discussions and coverage of floods (as well as droughts) in perspective. Floods are more exciting than droughts (which are exciting enough). But we learn and prepare better for future floods and droughts, if we focus more on the banality of these events and banal aspects of their management than on their unique extreme behavior and conditions.
Banality of Effective Drought Management
Similar reflections have been made on droughts (Lund 2015):
“By focusing on unique aspects of a drought, any drought can become an incredibly rare event. Becoming engrossed in the superlatives, however, can distract from the business of managing water shortages and preparing longer-term solutions.
What’s more relevant for water policy and management is the banality of drought. We should expect to see droughts in California of severity similar to the current drought about once or twice in a generation. Given climate change and the growth in expectations and values for diverse water uses, it seems reasonable to expect such droughts a bit more frequently than in the past. The warmer temperatures in this drought seem likely to become normal for future droughts, with disproportionate effects on ecosystems and small streams.
Agencies, cities, bankers, insurers, farmers and residents should prepare for greater regularity of droughts as harsh as the current one. Severe drought in California should be reclassified from a rare “act of God” to something more like a business cycle swing that recurs several times in a lifetime or career.
It is more important to focus on managing the dry event and preparing for future ones than understanding the fascinating intricacies of drought origins and statistics. But we probably will continue to obsess about drought statistics and El Niño anyway.”
Lessons for managing major water problems
We should obsess less with the cute facts and shiny science, and use the opportunities of extreme events and failures more to reflect on what could and should work better. Like aviation safety, we make flood and drought management more effective by learning and adapting from failures, even small and moderate failures. Ultimately, it is primarily failures and honest problem-solving responses to failure that keep management effective (Pinter et al. 2019).
Arguably, if we want to succeed in any problem, we need to organize ruthlessly to learn from failures and then provide sufficient resources, authority, accountability, and science to translate failures into smaller and less frequent future failures. We have had good success with this approach in aviation safety, public health, drinking water safety, and flood and drought management.
For problems lacking in political or professional will, a natural political tendency arises to ignore or normalize failures, or maintain that nothing can be done about them. We certainly do this in abundance with ecosystem failures and numerous social problems, which becomes a self-fulfilling strategy, rather than a problem-solving strategy.
Every major extreme event deserves an independently-minded postmortem identification of lessons and opportunities for improvement, more than a mere statistical discussion.
Arax, M. and R. Wartzman, 2005. The King of California: J. G. Boswell and the making of a secret American empire. Perseus Books.
DWR, California’s Snowpack is Now One of the Largest Ever, Bringing Drought Relief, Flooding Concerns, April 3, 2023.
Moyle, P. (2023), Lake Tulare (and its fishes) shall rise again, CaliforniaWaterBlog.com, April 16, 2023
Lund, J. (2015), The banality of California’s ‘1,200-year’ drought, CaliforniaWaterBlog.com, September 23, 2015.
Lund, J.R., J. Medellin-Azuara, J. Durand, and K. Stone, “Lessons from California’s 2012-2016 Drought,” J. of Water Resources Planning and Management, Vol 144, No. 10, October 2018.
Pinter, N., J. Lund, and P. Moyle. “The California Water Model: Resilience through Failure,” Hydrological Processes, Vol. 22, Iss. 12, pp. 1775-1779, 2019.
WELL WRITTEN LONG ARTICLE;BUT FIRST 5 PARAGRAPHS CAN BE SUMMARIZED IN FOUR ENTENCES. ALSO SOME STATISTIS OF RECORDBREAKING SAY THE 25 YEARS DATA COLD BE GIVEN AS AN SDDENDUM. THAT WAY THIS ARTICLE CAN BE MORE USEFUL.
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