Pre-Dam Comparisons-Working Page
From Glen Canyon Dam AMP
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.