 |
|
|
|
||||||
 |
|
||||||||
It consists of a productive and rare ecosystem, in which more than
311 species of vascular plants, 7 species of amphibians, 13 species
of reptiles, 47 breeding bird species, 11 raptor species and 23
mammal species can be found. Of major concern is the least Bell’s
vireo, a small endangered songbird that nests in the willows of
the Prado Basin. The wetland consists of a system of 50 shallow ponds that have been utilized to remove nitrogen in the river water since July 1992. The wetland system removes approximately 20 tons of nitrate a month and during the summer months concentration from 10 milligrams per liter to less than 1 milligram per liter. Several modifications have been made to increase the hydraulic capacity of the Prado wetland pond system, in order to handle a potential increase in future baseflows from the Santa Ana River, and to improve the operational flexibility of the system. Prado Dam is a key component for increasing local water supplies in Orange County. Historically, storm flows from the Santa Ana River have been lost to the ocean because flood flows took precedence over water conservation. However, a series of agreements between OCWD, the U.S. Army Corps of Engineers, and the U.S. Fish and Wildlife Service have allowed the District to conserve water behind the dam in a seasonal storage pool. The OCWD has also developed a treatment wetlands demonstration project for treatment of dairy washwater in the in the Santa Ana River watershed. The project involved redesigning dairy washwater storage ponds to maximize their utility, and employing a gravel-based subsurface flow treatment wetlands system. Site monitoring has documented water quality benefits including an approximate 90% drop in biochemical oxygen demand (BOD), and suspended solids (SS), a 30% decrease in total nitrogen and phosphorus and a 99% and 99.9% in total and fecal coliform bacteria. These results were based on a seven day residence time. The OCWD has recently completed construction of a series of six
modular wetland cells next to their Field Research Laboratory in
Anaheim. These wetlands will be used to test their efficacy in removing
lower concentrations of macronutrients such as nitrate and phosphate
and trace organic contaminants such as pesticides and pharmaceutical
compounds. The unique aspect about this and the dairy wetland is
the combination of plant and microbial processes within a gravel
matrix. Both systems have a monoculture of bulrush (Scirpus californicus)
that develops deep root systems within the gravel matrix. This allows
for the development of a microaerobic zone around the roots in the
anaerobic regions of the wetland. As the water moves through the
modular wetlands, it passes though several zones of oxidizing and
reducing conditions. This favors the breakdown of complex compounds
to ones that are more easily metabolized. This type of modular wetland
cell can be used to treat a variety of surface waters including
urban runoff. Fee: $45.00
The morning session will be spent on a walking tour of the San
Joaquin Marsh Reserve lead by Peter Bowler and Bill Bretz. The San
Joaquin Marsh is the largest coastal freshwater marsh in Southern
California. The marsh is managed by the University of California
Natural Reserve System (UCNRS). San Joaquin Marsh is a 202 acre
emergent marsh, over 100 acres of which are an emergent vegetation
wetland, and the other 50 acres The group will then be transported to Upper Newport Bay for a guided kayak tour of the Ecological Preserve by Kristina Finstad from the California Coastal Commission. Upper Newport Bay is one of the few remaining estuaries in Southern California and is home to nearly 200 species of birds, including endangered species, as well as numerous species of mammals, fish, other critters and native plants. The Bay is an important stopover for migrating birds on the Pacific Flyway. Come and see the various restoration measures that have been completed and are currently planned for the Preserve. Fee: $45.00
A section of Pacific Coast Highway will be elevated on a bridge over the new inlet and its jetties. Oil wells in the tidal basin and oil field contamination would be removed before wetland restoration is begun. A project description will be presented in the morning session on Saturday, followed by a tour of the site by Chris Webb from Moffatt & Nichol. In addition, the beaches in this area have had long term erosion problems related to a number of upcoast structures. Periodic replenishment has occurred, including innovative measures such as importing sand from the desert via train. The tour will include a visit to Seal Beach to view the coastal structures and learn about the current sediment management practices. Fee: $45.00 |
|
||||||||
 |
|
||||||||
2.
San Joaquin Marsh Tour And Upper Newport Bay Kayak Tour
