The Meetings continue

I enjoyed two great meetings this week and look forward to the last one of this series tonight. These meetings are open houses and meant to be forums for discussion. So far, we have talked more about silt and added a few topics--- for instance, shoudl the tributaries be managed differently than the main stem of Silver Creek?

Ecosystem Sciences Foundation has been knee deep in data and studies, and also knee deep in Silver Creek. Some of their VERY PRELIMINARY observations and discussion topics are as follows:

• The majority of sediment deposits in Silver and most tributary streams are “legacy” sediments from the early years of livestock grazing. Relatively recent studies seem to confirm this and that a sediment balance has been reached in Silver Creek in that the annual sediment inputs may equal the annual sediment exports.
• Current sediment sources occur during spring runoff from agriculture fields adjacent to streams that are not adequately buffered with riparian vegetation. Other sediment sources such as airborne (losses during tilling), bank erosion, muskrat activity, etc., are far less significant than the overland runoff.
• The average and minimum annual summer temperatures in Silver Creek are well below threshold temperatures for all trout life stages. Maximum summer temperature, generally at dusk, are high yet still below the threshold temperature for trout. Rapid temperature decline beginning at night fall ameliorates adverse affects on trout. In fact studies show substantial trout feeding activity at night.
• Neither temperatures nor sediments are currently having an adverse affect on Silver Creek trout populations; however, there is small margin for additional temperature increases or sediment deposition before a “tipping point” is reached in which trout numbers, recruitment and growth are adversely affected.

These are discussion topics only as ESF may revise them based on further investigation!!! Stay posted!

For the meetings in May, we can look forward to seeing these maps:
• Watershed Map: Basic map of what area will be included as
the “ecosystem”
• River-Tributary Map: Bellevue triangle including Big and Little Wood river connections
• Groundwater: Basic local of the aquifer(s) in triangle and major wells
• Land Use: Color coded for ag, rural, urban, preserve, etc
• Irrigation System: Use hydro graphics to map major canals and diversions
• Landform and Vegetation: riparian, etc
• Fish Habitat: Pools, riffles, runs
• Sediment Inputs: Using info from Goodman and Griffith/Minshall studies
• Sediment Deposition: Major sites of deposition in Loving, Silver
• Thermal Conditions: Using thermal imagery, temp data from data loggers)
• Steam Widening 1946 overlay on 2009 (with quantification)
• Buffer Zones: areas where ag land and tributary interface are or are not adequately buffered
• Stream Restoration: Map restoration projects as length of stream to illustrate connectivity and isolation
• Priority Areas: sediment input, channel overwidening, diversions/backwater, ponds, deposition zones, thermal loading, etc


What do we need now???
Your comments and old photos! Please use get us your comments, thoughts, photos, and information as soon as possible.
Thank you and hope to see you tonight at the Nature Conservancy office in Hailey at 116 1st ave. north, 5:30 pm.
Dayna