![]() ![]() “On the good news side, there is some increased use of new technologies for things like monitoring land subsidence.” “If we think about our prior drought, we had some unfortunate records set then: warmest years on record, record low statewide snowpack of only 5% of average in 2015, zero allocation to CVP ag contractors, and the first-ever state emergency response for dry private wells, not something the state had really dealt with before,” she said. She also noted that the conditions in the last two droughts have not had the same impacts as the large historical droughts. Jones pointed out that many of them are in the recent part of the historical record. The slide lists the droughts and how long they lasted. And the 21st century has not been great in terms of water supply availability.”Ģ1st century & 20th century droughts not the same “Interestingly enough, the slope is about the same as one of our driest periods in the historical record, which was the dry periods in the 1920s and 1930s, which actually was a severely dry time in the historical record. “We are in the downward-sloping portion of that smooth curve,” Ms. The graph below shows the annual statewide runoff for 1900 to 2020. Because realistically, there’s always a trade-off between risk and reliability.” “How many three-year droughts, four-year droughts, five-year droughts, etc? Because these are all things you consider when you think about how much reliability to have in your supplies and how much you can afford. “Think about how many two-year droughts we had in the past,” said Ms. The Department has also funded studies for smaller watersheds, such as Southern California, to help agencies manage their risks. The historical record has many more significant dry periods, sometimes twice as long as the state experienced in the droughts of the last 150 years. ![]() The Department has funded reconstructions using tree rings for the Sacramento River basin, the San Joaquin River basin, and the Colorado River basin going back over a thousand years. Studies of paleo records show that drought is a natural feature of California’s climate. But certainly, this is much better than where we were at this time last year.” So, in that sense, we’re still in the woods. ![]() “If you think about the groundwater, we have depleted much of our groundwater storage by having numerous drought years in the last decade or so, and one even very wet year will not recover that groundwater storage. “Not to say that the drought is by any means over,” said Ms. The state has experienced above-average precipitation, and storage in reservoirs is surging. The variability of precipitationĬalifornia has very highly variable annual precipitation and large seasonal precipitation variability. Declaring a drought emergency allows the Governor to direct state resources to respond to it. Droughts are a different type of emergency when compared to events like floods, fires, and earthquakes due to their very slow timescale. The state tends to focus on drought as a function of its impacts, which are typically regional or local, because it is the impacts that drive the responses.Ī common response to drought is the proclamation of a drought emergency. There are meteorological droughts, hydrological droughts, regulatory droughts, as well as drought indices and other sector-based definitions. Jones began by noting there are different interpretations of what drought means. This presentation was part of a series of panel discussions that the Commission has heard in recent months as part of their work on Action 26.3 of the Newsom Administration’s Water Resilience Portfolio, developing strategies to protect communities and fish and wildlife in the event of drought lasting at least six years. Jones provides insights on how the state tackles existing issues and future preparedness for drought. As Division Chief for Interstate Resources Management at the California Department of Water Resources, Ms. At the January meeting of the California Water Commission, Jeanine Jones took the commissioners through the history of past droughts and the lessons learned. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |