mid range streamflow forecasts for river management in the puget sound region l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Mid-Range Streamflow Forecasts for River Management in the Puget Sound Region PowerPoint Presentation
Download Presentation
Mid-Range Streamflow Forecasts for River Management in the Puget Sound Region

Loading in 2 Seconds...

play fullscreen
1 / 44

Mid-Range Streamflow Forecasts for River Management in the Puget Sound Region - PowerPoint PPT Presentation


  • 200 Views
  • Uploaded on

Mid-Range Streamflow Forecasts for River Management in the Puget Sound Region. Richard Palmer Matthew Wiley Department of Civil and Environmental Engineering March 21, 2005. Outline . Region’s Water Supply Basins Models Current Conditions Forecast Methods

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Mid-Range Streamflow Forecasts for River Management in the Puget Sound Region' - dalit


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
mid range streamflow forecasts for river management in the puget sound region

Mid-Range Streamflow Forecasts for River Management in the Puget Sound Region

Richard Palmer

Matthew Wiley

Department of Civil and Environmental Engineering

March 21, 2005

outline
Outline
  • Region’s Water Supply Basins
    • Models
    • Current Conditions
  • Forecast Methods
    • ESP, Extended Streamflow Prediction
    • CPC, Climate Predication Center
  • Current Forecasts
    • Water Snowpack Modeling
    • Streamflow Forecasts
    • Impacts on Storage

Special Thanks to the Water Forum for Funding the Mid-Range Forecasts

hydrologic model dhsvm
Hydrologic Model - DHSVM
  • Physically based, distributed model
  • Calculates energy and water balance at the grid cell level
  • 150 meter resolution, 3hr time-step
  • Station based meteorology
  • Output streamflows are aggregated to monthly total volume
  • Recently incorporated an experimental groundwater component
slide4
Sultan River
    • Snohomish PUD Hydropower project
    • Everett Water Supply
  • S.F. Tolt River
    • Seattle Water Supply
  • Cedar River
    • Seattle Water Supply
  • Green River
    • Flood Control
    • Tacoma Water Supply
  • All have environmental flow requirements
streamflow forecasts
Streamflow Forecasts
  • Initialize basin models to current conditions using recent observed meteorology
  • ESP (Extended Streamflow Prediction)
    • Project 13 months into the future using each year in the historic record as one of many possible scenarios (traces).
    • Forecast can be conditioned using subsets of years based on observed climatologically conditions, such as ENSO state
  • CPC (Climate Prediction Center)
    • Seasonal outlooks of the probability of deviations from normal temperature and precipitation for 13 months
    • Each season's outlook and probability that a temperature or precipitation quantity will be exceeded for a climate region at the given lead time of two weeks to a year.
modeling snowpack
Modeling Snowpack
  • DHSVM allows evaluation of snowpack conditions over time
  • Provides graphical presentation of basin state
  • Estimate of total water storage as snow
  • Essential for evaluating the future based on current conditions
  • Provide spatial information to complement Snotel and Snow Course information
slide13
Forecasts Results
    • USGS 12137290
    • SULTAN1: Inflow to Spada
    • USGS 12147600
    • TOLT1: Inflow to SFT
    • TOLT2: Below SFT
    • USGS 12115000
    • USGS 12117000
    • CEDAR1: Inflow to CM
    • CEDAR2: Below CM
    • HH_INFLOW: Inflow to Howard Hansen
implications to water supplies
Implications to Water Supplies
  • Factors to Consider
    • Current storage
    • Inflows to reservoirs
    • Inflows below reservoirs that contribute to fish requirements
    • Average demand and effect of conservation
    • Availability of supplemental groundwater supplies
    • “Normal” versus “Low” versus “Critical” instream flows
  • Examined Seattle and Tacoma systems
implications for puget sound water supply systems
Implications for Puget Sound Water Supply Systems
  • Inflows to reservoirs expected to be only 40% to 50% of average, slightly higher in the Everett system.
  • 60% chance of the Seattle system not completely refilling this spring ( ~32 billion gal.)
  • 10% chance of the Tacoma system not completely refilling this spring (~10 billion gal.)
  • If NO action is taken:
    • (i.e. “Normal fish flows, average demand)
    • 10%-15% of shortfall by October.
implications for puget sound water supply systems26
Implications for Puget Sound Water Supply Systems
  • A 10% reduction in consumption reduces probability to around 5% chance of shortfall
  • Current snowpack is only half of the picture, spring rains can also refill reservoirs
  • 10-12 inches* (at Seatac) between March 1 and July 1 will get us to near average storage by September 1 *(Average precip is 9.5 inches)
  • In an average year there is a considerable “surplus” of water in the basins
implications for puget sound water supply systems27
Implications for Puget Sound Water Supply Systems
  • Actions have already being taken
  • Actual operations are very dynamic with considerable flexibility and continual adjustments based on evolving conditions
  • Minimizing ecological damage and preventing disruptions to customers are primary goals
  • A “serious” situation requires several events (low snow pack, below average summer flows, late return of rain)