The Portland General Electric (PGE) Bull Run Hydroelectric Project was decommissioned beginning in 2007. A series of studies were initiated to predict and/or monitor the effects of the removal of Marmot Dam in 2007 and the Little Sandy Dam in 2008.
The following are different projects of the sub-type Little Sandy Dam/Marmot Dam Removal Effects that have occurred in the Sandy1 reach.
Alternatively, you can see details on all projects of the sub-type Little Sandy Dam/Marmot Dam Removal Effects in the Sandy River Basin.
Bedload measurements indicate the quantity and size distribution of non-suspended particles being moved by a river or stream's current past a given point per unit of time. Equal-width integrated samples of bedload were taken at several sites along the Sandy River, generally associated with gaging stations. The results help document the downstream movement of sediments released by the removal of Marmot Dam.
Reports and Data
The size composition of river-bed substrates were surveyed at various sites in the Sandy River after a lahar flow event in 2000. The results were compared with those of similar surveys conducted before the lahar flows. The comparison illustrated what could happen when the removal of Marmot Dam in 2008 released a wedge of sediment built up behind the dam.
Reports and Data
PhD dissertation. The sediment storage potential of the Sandy River below Marmot Dam was estimated using field measurements of sheer stress and patterns of deposition following a lahar flow event in 2000. The results were intended, among other things, to indicate what could happen when the removal of Marmot Dam in 2008 released a wedge of sediment built up behind the dam.
Reports and Data
Wolman pebble counts are used to characterize the relative abundance of rock particles of various sizes on the surface of the riverbed. The size of particles are measured at regular intervals across the width of the channel. The results were used to predict and prepare for the consquences of the removal of Marmot Dam.
Reports and Data
Suspended sediment measurements indicate the quantity and size distribution of suspended particles being moved by a river or stream's current past a given point per unit of time. Equal-width integrated samples of suspended sediment were taken at several sites along the Sandy River, generally associated with gaging stations. The results help document the downstream movement of sediments released by the removal of Marmot Dam.
Reports and Data
