If you look at this chart for Hetch Hetchy, you can see that the biggest and steadiest rise is between March and July, https://waterdata.usgs.gov/monitoring-location/11275500/#parameterCode=00054&period=P365D&compare=true. Northern California's reservoir levels continued to rise in the week after an atmospheric river slammed the state with torrential rain and high winds. Emissions must be offset by dedicated conservation programs or renewable energy generation such as wind or solar. The water system, which includes the landmark Hetch Hetchy Reservoir, is expected to fill this winter, for the first time since 2019, with nearly 1.5 million acre-feet of water. Only modest new supplies would be required in the driest years. Great visualization Chris! Take CA Highway 120 from the park toward Groveland. With modest additional investments San Francisco will be able to maintain an uninterrupted supply of high quality Tuolumne River water. It is on the graph. earthquake. I also added the ability to select specific reservoirs to display on the graph and share a custom URL which will point those selected reservoirs (click on list button on top right of dashboard). Hetch Hetchy is only one of nine reservoirs in the San Francisco Public Utility Commission's water system. Secure .gov websites use HTTPS She has been with SFGATE for more than 10 years. environmental context. Folsom Lake is letting the water flow out. In the year prior to Oroville reaching capacity the interactive chart showed the rate of inflow over time. Hetch Hetchy Reservoir in Yosemite National Park is seen in 2022. Flood control agencies (not DWR) have the most say in regard to releases. Wife of missing Bay Area radio host says Jeffrey Vandergrift will not Sen. Dianne Feinstein is hospitalized in San Francisco with shingles, California extends deadline to file 2022 income taxes to match IRS decision, Here's where California reservoir levels stand after this week's rains, Going to Tahoe this weekend? Sometimes this is well done sometimes it is poorly done. More about the Tuolumne River Voluntary Agreement can be found athttp://www.tuolumnerivermanagementplan.com. I know this might be difficult to display but Im very curious on the actual amounts of water consumed on a monthly basis and if this is somehow processed in a certain between what is agricultural and what is non-commercial etc? https://cdec.water.ca.gov/dynamicapp/QueryDaily?s=HTH One of the big challenges in water management is controling the release. San Francisco voters have demonstrated their opposition to There doesnt seem to be any site that shows the impact of each storm. Kellie Hwang is the newsletter editor for The San Francisco Chronicle. As of Feb. 1, the systems total water storage was just over 1.3 million acre-feet, or about 92% of capacity. Upcountry and the Bay Area. Restoring Hetch Hetchy will require some changes in how San Francisco moves and stores water. Just in case a large storm hits, that way they dont reach 100% capacity. McClintock bill proposes to improve public access at Hetch Hetchy. The valley is Thanks. Reservoir behind OShaughnessy Dam does not require filtration. It updates hourly using data from the California Department of Water Resources (DWR) website, giving an up-to-date picture of California reservoir levels. Your tools are awesome just hurts when you receive bad data at times! If we reach 100% after the current rains and then it stops raining for the season, then our percentage will start going down. function reloadiframes(){ a broad meaning that had been previously applied in an Historical average is near unattainable these days. GNSS2 - Level 2 Quality Survey Grade Global Navigation Satellite System. These graphs will always read low because they represent the percentage of the seasonal average at some point before the end of the season. The tremendous inflow to city reservoirs during the recent storms, mostly in and around Yosemite National Park, has lifted San Franciscos total water storage to near capacity. Sierra Club unsuccessfully fought the reservoirs establishment It has no natural inflow or out flow. This is a marimekko (or mekko) graph which may take some time to understand if you arent used to seeing them. 1 kaf is the amount of water that would cover 1 acre in one thousand feet of water (or 1000 acres in water in 1 foot of water). But Sites would be what's called an off-channel . For most of the year it will still be possible to divert the flow of the Tuolumne River into the pipeline just downstream of the National Park boundary. Wife of missing Bay Area radio host says Jeffrey Vandergrift will not Sen. Dianne Feinstein is hospitalized in San Francisco with shingles, California extends deadline to file 2022 income taxes to match IRS decision, Going to Tahoe this weekend? What period does CA use for Historical Average? It will be very different depending on the period chosen. Share sensitive information only on official, secure websites. //this function is called from the javascript from within the iframe after the contents of iframe are loaded (and after an additional 150ms delay) She is a University of Washington graduate. The worst possible scenario is it just remains completely dry. In addition, San Francisco receives approximately one-tenth of its power from hydroelectricity generated by the gravity-driven flow from the Hetch Hetchy Reservoir. . Major snowstorm might leave you stranded, New 101 express lanes opens in Bay Area. So many facets beautifully chartered. Shasta is the reservoir with the largest capacity and so it is the tallest row. San Franciscos water system, which includes Hetchy Hetchy, is expected to fill this winter for the first time since 2019. The construction of the Hetch Hetchy Railroad took place from 1915 to 1918. Data have been checked by the reporting agency. How can I match up other monitoring locations similar to the ones on this Interactive Dashboard? This other page: Ill pass it along to friends. I think the problem is with the CDEC database (as the LakesOnline website also has had incorrectly high information). Secure .gov websites use HTTPS Current and Historical Visualization, https://cdec.water.ca.gov/dynamicapp/QueryDaily?s=HTH, https://cdec.water.ca.gov/dynamicapp/QueryDaily?s=SHA, https://engaging-data.com/ca-reservoir-level/, https://cdec.water.ca.gov/reportapp/javareports?name=RES, Visualizing Californias Water Storage Reservoirs and Snowpack, Interactive California Reservoir Levels Dashboard. SFPUC said as of this week, the Hetch Hetchy reservoir is at 92 percent capacity. This chart only shows reservoirs filled via natural flow/rainfall. Located within the boundaries of Yosemite National Park, the reservoir saw a sizable 21.31-foot bump in its water level and gained 36,300 acre-feet, according to Tuesday data from the U.S. Geological Survey. We provide water directly to customers in San Francisco and wholesale through 26 Water agencies in Alameda, Santa Clara, and San Mateo counties. In 2007, the Bush Save my name, email, and website in this browser for the next time I comment. Forty-six percent . I will take a look and see if there are other important reservoirs missing and may add them in the future. Add a button to convert the row heights to log scale. California Reservoir Levels - Dashboard and visualization showing current water levels in California reservoirs . The main reason for the discrepancy, the department said, is that the focus of the atmospheric river was generally between the Golden Gate and Mount Lassen, meaning that the Feather River watershed received much more rainfall than the Shasta Lake drainage area. Greetings from Mount Laurel New Jersey. Draining Hetch Hetchy without depriving Bay Area residents of Other California water agencies have done far more to reduce the impact of their system on Mono Lake, the Trinity and San Joaquin Rivers, and the Bay-Delta. If we reach 100% after the current rains and then it stops raining for the season, then our percentage will start going down. The cities, water districts and private utilities represented by the Bay Area Water Supply and Conservation Agency (BAWSCA) rely upon the Hetch Hetchy system for water to protect the health, safety and economic well being of 1.8 million citizens, businesses and community organizations. Hetch Hetchy Water System The system originates more than 100 miles from its primary customers, in Yosemite National Park. This was helpful to project seasonal trends & storm impacts. Call 209-372-0200 for the latest road and weather conditions, Hetch Hetchy Road Daily Hours: 8 am to 5 pm Why isnt Lake Sonoma included? This almost happened with the Orville Dam in 2017. Lots of possibilities, just curious. Trinity Lake, with a capacity of 2,447,650 acre-feet, had the smallest increase, from 29% in December to 30% in January. Over the summer, Gov. O'Shaughnessy Dam is a 430-foot (131 m) high concrete arch-gravity dam in Tuolumne County, California, United States.It impounds the Tuolumne River, forming the Hetch Hetchy Reservoir at the lower end of Hetch Hetchy Valley in Yosemite National Park, about 160 miles (260 km) east of San Francisco. This other page: https . Not only does it supply 85 percent of the water for 2.6 million people in San Francisco, controlled releases via the O'Shaughnessy Dam are helping preserve downstream specieseven in dry . We own and operate the Hetch Hetchy Regional Water System which serves 2.7 million customers. the Bay Area. Didnt realize how bad things were there. To reach Hetch Hetchy, you have to exit Yosemite National Park and re-enter it. proposed as a source of water following the 1906 San Francisco YTD values are from January 1 . Why is it not listed? The OShaughnessy Dam, which was completed in 1938 and is 430-feet tall, impounds water in Hetch Hetchy Reservoir for communities in the Bay Area. Locked padlock The SFPUC has consistently stated that voluntary agreements are the best path forward for the Bay-Delta, as the voluntary agreement strikes the right balance between environmental stewardship and water reliability. window.addEventListener("orientationchange", function() { I was thinking that it would be interesting to compare inflows and outflows. Thanks for providing it for public information. According to the SFPUC, the upper reaches of the Tuolumne River have received about 36 inches of rain since the start of the water year in October, almost as much as what the area averages in a year. Park visitors walk across OShaughnessy Dam in Yosemite National Park on Sept. 1. Great resource! If a reservoir gets filled to 100% and more, the dam will break and many cities will get flooded, so the operators are careful. Another not monitored by the State? }, 150); Lock Getting There. I would like to make one small suggestion:. One of the most impressive was Hetch Hetchy, which provides drinking water to 2.6 million people in San Francisco and other Bay Area communities. Water is rapidly flowing into the state's reservoirs. San Francisco will be in great shape going into 2023, said Spreck Rosekrans, executive director of Restore Hetch Hetchy Its unfortunate that too little is being done with these flows to recharge groundwater basins to help cities and farms and even restoring Hetch Hetchy Valley., Kurtis Alexander is a San Francisco Chronicle staff writer. If you are reading this, its probably the winter rainy season in California again, and time to check on the status of the water in the California reservoirs. The water transmission system in the Bay Area and Peninsula includes the Bay Division, San Andreas, Sunset Supply, and Crystal Springs pipelines. What rates am I paying? Major snowstorm might leave you stranded, New 101 express lanes opens in Bay Area. "Soils that have become hydrophobic due to wildfire can also contribute to increased runoff because the water is less able to penetrate the burned soil," the department said. All rights reserved. So while that is kind of good news, he said, things start to look more grim after January produced paltry rainfall and, so far, February has also been dry. This is a great and very thoughtfully designed web site! Trailhead address: Evergreen Road (Hetch Hetchy Road), Yosemite National Park, CA 95321. This is my first year watching the levels, so maybe Im missing something. Delivering approximately 260 million gallons of water per day, the regional system consists of over 280 miles of pipelines, over 60 miles of tunnels, 11 reservoirs, five pump stations and two water treatment plants. Thanks for the link. Very nice work. I wonder why it doesnt work for you. The upcountry portion of the System begins with Hetch Hetchy Reservoir in Yosemite National Park. Hetch Hetchy has generated controversy since it was first May 24, 2022 - BAWSCA Statement About the Adoption of a Systemwide Water Use Reduction of 11%. O'Shaughnessy Dam was built on the Tuolumne River in 1923 to create Hetch Hetchy Reservoir. One gauge in the area has measured 6.12 inches since Oct. 1, which is 899% of normal. The judge also noted the provision of the state San Francisco and the thousands of suburban . "This was rare for October. The snowpack acts as a natural reservoir and slowly releases water.. Maybe just acre/ft with ^ or down arrow. Could you also do the same for the Colorado River reservoirs to see how they are fairing? The group says the recent plethora of water shows that the city could do without Hetch Hetchy Reservoir, by using other storage facilities that have filled and pursuing new projects to capture the surplus. Thats up more than 400,000 acre-feet since early December, before the unrelenting series of atmospheric river storms blew through California between Christmas and mid-January. "In contrast, the Shasta Lake drainage had only a couple of stations in excess of 10 inches whereas most received less. She was previously an engagement reporter. Current conditions of LAKE OR RESERVOIR WATER SURFACE ELEVATION ABOVE NGVD 1929 and RESERVOIR STORAGE are available. Absolutely zero reason to be releasing this much water from these reservoirs. The soaking was welcome in a drought-plagued state with a diminishing water supply. provides water to 2.7 million residents and businesses in the San This is a very clear graph and I cannot imagine the hours you have put in while setting it up and doing the maintenance. Californias snowpack slips below average after dismally dry January, renewing concerns about drought, Busting water limits wont cost you in Marin County: Penalties canceled as rain fills reservoirs, California snowpack hits highest level this century for March. She is also an alumna of Reveal from the Center for Investigative Reporting Investigative Fellowship and The New York Times Student Journalism Institute. During the winter months, they let water out of the reservoirs in anticipation of large storms. 1 covering up to $875 million and much of the rest coming from federal loans to water suppliers. Current conditions of LAKE OR RESERVOIR WATER SURFACE ELEVATION ABOVE NGVD 1929 and RESERVOIR STORAGE are available. Lake Shasta, the state's largest reservoir, rose 2.9 feet and added 31,020 acre-feet of water. They also built a spillway that was too steep and did not install energy dissipators along the spillway. Hetch Hetchy is one of nine reserviors in a water system that serves San Francisco and other Bay Area communities. It certainly looks dry at least until the last week in February, he said. What happened to the Hetch Hetchy level? Hetch Hetchy is Monitoring location 11275500. Thank you! That includes the Tuolumne River, which provides water via Hetch Hetchy Reservoir to Bay Area customers. Just a wistful thought, it would be really cool to graph the water release statistics. Its water supply Hetch Hetchy Reservoir, in the Sierra Nevada is 80% full, . Your Privacy Choices (Opt Out of Sale/Targeted Ads). Wapama Falls (moderate) 5 mi (8 km) round-trip; 2 hours. But they'll cost you, Fight at high school basketball game in S.F. How can I apply to SFPUC? The SFPUC has voiced concerns with the Plan, as it would dramatically reduce the agencys water supply, leaving it subject to significant rationing in droughts and more extreme weather conditions brought on by climate change. Previously, Kellie covered dining news and trends, visual arts, events and nightlife for the Arizona Republic, and freelanced for the former Contra Costa Times. The Hetch Hetchy reservoir, which supplies water for San Francisco and other parts of the Bay Area, was at 77% of its 360,000-acre-feet storage capacity in January compared to 73% in. The main goal of this visualization is to provide a quick overview of the status of the main reservoirs in the state and how they compare to historical levels. The overall storage is said to have dropped by 57.4 to 56.4 (or 302 kaf). If you look at the inflow data on the major reservoirs, its pretty flat. https://cdec.water.ca.gov/dynamicapp/QueryDaily?s=SHA November 10, 2022 - BAWSCA Statement on State Water-Policy Officials, SFPUC, and Districts Sign MOU for Tuolumne River to Help Recover Salmon While Protecting Water Reliability. But tearing down O'Shaughnessy Dam in order to restore Hetch Hetchy Valley would be a disaster. This file photo shows Shasta Lake. The citys water system also includes a water bank at Don Pedro Reservoir along the Tuolumne River, which was full as of Feb. 1. It could be the 180% of historical average of snowpack, which will be melting in a couple months. Great work. The recent spate of storms lifted the statewide snowpack to 190% of average for the start of the month, and more snow is on the way. Have you looked into that side of the water management equation? This dashboard provides a bit more detail on the state of each of the reservoirs while also showing an aggregate total. I believe the spillway was designed by the State. I had a class in spillway design many years ago. I would turn this graph, 90 counterclockwise, and start the capacity along the bottom axis from left to right, with the biggest reservoirs on the left and the smaller ones on the right. Best of luck out there in California! Part of the lake is on the California side, but it has zero California water impact beyond the immediate Tahoe residents. Could you also show each reservoirs level as a function of time? Curt, Good point re the colder weather dropping more snow instead of rain at higher elevations this year. **new combined California reservoir and snowpack visualizer**, made a bar graph showing the overall level of water in the major California reservoirs, the California Department of Water Resources (DWR) Data Exchange Center. One acre-foot is the equivalent of one acre of land covered in one foot of water. P.S. Instructions: Francisco Bay Area. BAWSCA agencies also are implementing water conservation and water recycling projects to help preserve this precious resource for their communities, and are working to identify alternate sources of water supply. Climbers Timmy O'Neill (left) and Lucho Rivera atop a wall overlooking Hetch Hetchy Reservoir. Thats a very poor design. in 2018. }, false); Lake Tahoe really isnt part of California water, as the outflow goes to Nevada. Navigation and Navigable Waters 33.208.82 Hetch Hetchy, Cherry Valley, and Don Pedro Dams and Reservoirs. I second that request. Its supposed to be brown. The half-hour drive to Hetch Hetchy from CA Highway 120 begins outside the park boundaries. I live in the central valley. In another sign that Californias drought is easing, San Francisco captured more than a years worth of water in just one months time. Although Hetch Hetchy Reservoir is the most well-known, it stores less than 25% of the systems water. Curious why Shasta lake seems to be making big gains in water coming in and Trinity not so much? Should be fixed at some point. I notice Briones Reservoir is not on the list. "It is unknown how much area of the Feather River and Shasta Lake drainages are impacted by hydrophobic soils.". In 2021, the SFPUC and the Modesto and Turlock Irrigation Districts launched a proactive pilot program with the U.S. https://engaging-data.com/ca-reservoir-level/ by the Raker Act. Partly because of low water, the rivers chinook salmon runs have plummeted from tens of thousands of fish annually a few decades ago to fewer than 1,000 in recent years. Saved to my favorites now. California snowpack hits highest level this century for March. System for more than 60 percent of their drinking water. I noticed that Folsom does not change whereas every reservoir changes on an hourly update. reloadiframes(); Visualization was done in javascript and specifically the D3.js visualization library. I realize there we dont want to reservoirs overflowing, but why are we still below historical average? What happened to the Hetch Hetchy level? Hetch Hetchy is the only reservoir above its average storage of 63%, and is 82% full. Eighty-five percent of the water comes from Sierra Nevada snowmelt stored in the Hetch Hetchy reservoir situated on the Tuolumne River in Yosemite National Park. From the main road, it's about a 20- to 25-minute drive to the parking area. The San Francisco Public Utilities Commission is involved in on-going negotiations with the State on a voluntary agreement for implementation of the Bay-Delta Plan, which calls for large increases in water releases on the tributaries to the San Joaquin River, a major tributary to the Bay-Delta. . Especially for small ones it is hard to identify them and click on them. A .gov website belongs to an official government organization in the . Its important to note that other communities in California have taken actions in far greater magnitude than SF to make our waterways more sustainable. hetch hetchy reservoir level percentage Rivers and Streams Streams draining into the Peninsula Watershed within the project area are relatively small, steep, and in a 2021-11-17. It would be really interesting to visualize whether were able to replenish ground water this year after all the precipitation. rejected by an appellate court and the California Supreme Court Why is Lake Nacimiento and Lake San Antonio not listed? Monitoring location 11277200 is associated with a LAKE, RESERVOIR, IMPOUNDMENT in TUOLUMNE COUNTY, CALIFORNIA. Official websites use .gov San Francisco's water-bank in Don Pedro Reservoir, downstream on the Tuolumne River, holds twice as much water as Hetch Hetchy. Twenty of San The Bay Area transmission system also includes Irvington Tunnel 1 and Tunnel 2, the Bay Tunnel, and the Crystal Springs Bypass Tunnel. Its fluctuating between ~107% and ~20% from one hour to the next (reading 107.6 atm). Email: kalexander@sfchronicle.com Twitter: @kurtisalexander. The data on water storage comes from the California Department of Water Resources (DWR) Data Exchange Center. James Q. Martin / Restore Hetch Hetchy Show More Show Less 4 of 7 Monitoring location 11277500 is associated with a LAKE, RESERVOIR, IMPOUNDMENT in TUOLUMNE COUNTY, CALIFORNIA. Also, do they provide inflows and outflows for locations? pertained to water that was wasted, and there was no claim that Rizzardo said there was a decent amount of flow into the reservoirs into January, even though weather-wise it was bone dry, a result of lower elevation snow at 4,000 to 6,000 feet making its way into the reservoirs. DWR is one of many local, State and Federal entities that dictate water releases. If you are experiencing a water, power, or sewer emergency or service problem call our 24-hour hotline at 3-1-1 or (415) 701-2311 from outside SF or log on at, Public Notices and Public Meeting Notices, Customer Assistance Program - Water/Wastewater, Customer Assistance Program - Hetch Hetchy Power, Hetch Hetchy Power Medical Necessity Assitance Program, Hot Water Recirculation Pump Rebate Program, San Francisco's Urban Watersheds Overview, Free Phone Consultations, Evaluations and Devices, Games Puzzles Virtual Backgrounds Overview, Get your Free 2023 Pollution Prevention Calendar, Construction & Contracts Overview Overview, Contract Opportunities and Payments Overview, Project Review and Land Use - Hetch Hetchy Water and Power, Project Review and Land Use - San Francisco, Sewer System Improvement Program Overview, Water Infrastructure Improvements Overview, Boards, Commissions and Committees Overview, Internships, Apprenticeships and Youth Employment, Public Notices and Public Meeting Notices Overview, Audited Financial Statements & Annual Comprehensive Financial Reports, SFPUC Preliminary Public Power Options Report, Civic Center Sustainable Utilities District Plan, Resolution Condemning Systemic Racism & Taking Action to Promote Racial Justice. Remaining Capacity text in the legend should be brown? So they should be saving much more and deal with the .000001 of risk later. Article X, Section 2 that requires diversions for all water Good info to know. Impounded by O'Shaughnessy Dam, Hetch Hetchy Reservoir water passes through hydroelectric powerhouses before it enters the San Joaquin Pipelines, the Tesla Ultraviolet Treatment Facility, and the Coast Range Tunnel on its journey to the Bay Area. Constitution used to support the arguments to remove the dam was I like the comparisons of last year, and the historical average. Voters rejected a 2012 A lock ( At this facility, which is shared with other water agencies, the city can stash water for credits against future draws on the river. Its not possible to see or really interact with the tiniest slivers. The height of the row indicates how much water the reservoir could hold. Last week, I paid a visit to Hetch Hetchy. This local water is captured in reservoirs located in San Mateo and Alameda counties. Your email address will not be published. 501(c)3 organization, federal tax ID #942419885. Heres where California reservoir levels stand after this weeks rains. A truly excellent project. Great graphs and very useful. Restore Hetch Hetchys subsequent appeal to the ruling was Most local reservoir inflow timeseries are too short to calculate long-term values. Love easy to read and understand information. Fish and Wildlife Service that provides an immediate $4 million investment for habitat improvements for fisheries in the Tuolumne River. Hi, I started by using this page (https://cdec.water.ca.gov/reportapp/javareports?name=RES) to determine which reservoirs to include and for some reason Almanor isnt on the list. You can sort the mekko graph by size largest at the top to smallest at the bottom or by reservoir location, from north to south. Commission. and its snowmelt-fed water supply, water from Hetch Hetchy Hetch Hetchy Level before the storm: 3,729.68 feet Level after the storm: 3,750.99 feet Total rise: 21.31 feet Storage before the storm: 221,500 acre-feet Storage after the storm: 257,800. I see many of the local canals flowing with lots of water. Prior to The Chronicle, she worked as a data journalist for Honolulu Civil Beat, a watchdog news organization covering the Hawaiian islands. San Francisco operates three medium-sized hydro-electric power plants in the Tuolumne River watershed Kirkwood, Moccasin, and Holm. Find out more about the system at http://www.sfwater.org, BAWSCA Board Policy Committee Meeting, April 12, 2023 1:30pm. Similar to the water supply issues discussed above, the amount of power replacement is small in a statewide context less than of 1% of the renewable power supply being developed this decade alone. Ive been meaning to search for aquifer levels. San Franciscos Hetch Hetchy water system is almost full for the first time in years. Isabella is filling quite slowly in order to test out the new $500 million spillway. Although Hetch Hetchy Reservoir is the most well-known, it stores less than 25% of the system's water. Within San Francisco, we manage water distribution in the City. Hetchy Reservoir can store as much as 117 billion gallons for the Tracy Barbutes, Freelance / Special to The Chronicle, Heres where California reservoir levels stand after this weeks rains. located in a national park and it passed the Raker Act in 1913 to mandate within The north (side of the reservoir) usually has two waterfalls going at the best of times, but youll see up and down the canyon walls, if you look close, you count there are about 12 waterfalls running now, said Steve Ritchie, the SFPUCs assistant general manager of water enterprise, during a recent drought report to the agencys governing board. The average for this time of year is approximately 4,659.57ft, plus or minus 39ft. Having it here would be great! Current conditions of LAKE OR RESERVOIR WATER SURFACE ELEVATION ABOVE NAVD 1988, LAKE OR RESERVOIR WATER SURFACE ELEVATION ABOVE NGVD 1929, and RESERVOIR STORAGE are available. Monitoring location 11275500 is associated with a LAKE, RESERVOIR, IMPOUNDMENT in TUOLUMNE COUNTY, CALIFORNIA. drained by the Tuolumne Water is such a fascinating topic and Id hate to have to be a water manager making a decision on how much to release to avoid reservoir flooding. Thats just another very strong indication visually that its a big water year.. While forecasters can predict the likelihood of future rainfall over large areas, they cant pinpoint it to the degree needed to determine whether a particular watershed/reservoir will overflow and cause damage and loss of life. Really appreciate the work you did to build this graph. 7 days 30 days It can take several days to see the full impact on reservoirs as water continues to run through watersheds and into streams in the days after a storm.