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Conventional engineering methods of flood control design focus narrowly on the efficient conveyance of water, with little regard for environmental resource planning and natural geomorphic processes. Consequently, flood control projects are often environmentally disastrous, expensive to maintain, and even inadequate to control floods. In addition, maintenance programs to improve flood conveyance and enhance levee stability, such as clearing riparian vegetation in channels and on levees, undergo little – if any – technical scrutiny. Such programs are often prescriptive in nature, rather than...

Retention of particulate and dissolved nutrients in streams is a major determinant of food avail-ability to stream biota. Retention of particulate matter (leaves) and dissolved nutrients (nitrogen) was studied experimentally during summer 1987 in four 300-500 m reaches of Lookout Creek, a fifth-order stream in the Cascade Mountains of Oregon. Constrained (narrow valley floor) and unconstrained (broad valley floor) reaches were selected within old-growth and second-growth riparian zones. Gingko leaves and ammonium were re-leased into the channel and retention rates were measured. Retention...

As part of a brief study tour in California, I had the good fortune of spending a very pleasant day on the Caspar Creek watershed, ably guided by Peter Cafferata and Liz Keppeler. Amongst the many notable achievements of the Caspar Creek Study is its longevity. The study started in 1962 and has evolved over time

Native plant and wildlife communities along Northern California's middle Sacramento River (Red Bluff to Colusa) originally adapted to a changing pattern of erosion and deposition across a broad meander belt. The erosion-deposition process was in balance, with the river alternately building and eroding terraces. Human-induced changes to the Sacramento River, including bank protection, gravel mining, pollution, riparian vegetation removal, flow regulation, and flood control, have resulted in a number of physical and ecological effects. This study focuses on changes in bank erosion, bank...

Riparian communities established along Elder Creek, a tributary of the upper South Fork Eel River, are bounded by two frequencies of periodic flooding. The upper limit for the riparian zone occurs at bankfull stage. The lower riparian limit is associated with a more frequent stage height, called the active channel, having an exceedance probability of 11 percent on a daily average flow duration curve. Distinct tree communities occupy bankfull and active channel zones. Riparian densities (trees per meter of stream channel) along the active channel decreased with increasing channel gradient...

A probability sampling method called SALT (Selection At List Time) has been developed for collecting and summarizing data on delivery of suspended sediment in rivers. It is based on sampling and estimating yield using a suspended-sediment rating curve for high discharges and simple random sampling for low flows. The method gives unbiased estimates of total yield and variance. The technique has been modified by replacing the rating curve with a user-specified average sampling rate function. This function allows easier specification of field sampling parameters for specified conditions and...

Lack of information on the status of hardwoods, particularly oaks (Quercus sp.), is creating concern in California that continued fuelwood harvest will aggravate erosion and sedimentation (Pillsbury et al. 1983). This concern is unsupported by data from the West Coast because few data exist, a fact ackowledged by Pillsbury et al. (1983).