Pre-Dam Comparisons-Working Page

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Under construction- Data Collection page

[Source: AZ Wildlife Views- Sep-Oct 2012 -Bill Stewart]

  • In any given year, flows ranged from less than 1,000 cfs to more than 100,000 cfs"
    • Today, flows rarely get above 31,500 cfs (maximum power-plant capacity) and rarely below 5,000 cfs
    • Flows are more stablized
  • Water temperatures went from near freezing in winter to above 85 degrees in summer.
    • Today, steady temperatures between 45 degrees and 50 degrees. (mainly because water is drawn from near the bottom of the lake)
  • The river went from being heavy laden with turbid, brown sediment to flowing with very clear water.
    • Sediment a fraction of what it once was

  • Drift in the system changed.
  • What was riparian vegetation like pre-dam??

Positive Impacts from Dam

  • The cool, clear water has created one of the best tailwater rainbow trout fisheries in the nation at Lees Ferry.

  • Pre-Dam Flows: Large spring snowmelt floods, erratic summertime flows, and low flows from November-March.
  • SEDIMENT:
  • WATER TEMPERATURE:
  • RIPERIAN ZONE: nearly barren shoreline pre-dam. Did not contain large amounts of vegetation..., essentially it did not support significant amounts of plants.