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I ■ Page 4 CAMASSIA Study Looks at Restoring Lower Amazon Creek Wetland The U.S. Army Corps of Engineers is studying The purpose of the Amazon Creek restoration study is the possibility of restoring a section of Amazon Creek to restore environmental resources, including fish and to its historic flood plain and surrounding wetland. wildlife habitat lost as a result of flood- control projects, while continuing to provide flood- control benefits. The Amazon Creek" study area (see map, page 3) Typical Channel - widening Cross Section includes the lower Amazon Creek from Danebo Av- enue downstream to Green Hill Road, as well as the section of the "A" Channel from the diversion struc- ture to Green Hill Road and the section of the "A3" Channel from Danebo Avenue to the "A" Channel. This area was chosen because it offers the highest wet- land restoration potential. Paved The study looks at several options: 1 Wet Season Flow • Remove sections of the existing channel levee Surface Existin along the Amazon and "A" and "A3" channels, re- Existing Dry Season Flow ._ \ tain a low -flow channel to direct dry- season flows, / widen the channel, and reduce bank slopes as shown ■ tih.• / • � in the cross section to the left. Wetland vegetation .`' it ld be in bottom, ::' w ou e esta n the canne ottom, while " " -gviltprol �,r mnre 4 , L , maintenance and clearing requirements would be re s° ,,. u •��a Y ,4e r'` • duced. These changes would allow wetlands adjacent ~' " 1 ' te $ TA . to the channel to flood periodically. 1 u • Modify the levees. Under this alternative, the 1 4• , t~ existing levees would either be breached with culverts r o I = or "notched" by removing a small section to allow ad � tt cd ' r, A — ditional water into wetland areas. This option is less E G.p„ .. ' o,4 Cdd expensive than levee removal and allows easy control I U 14 p - a GG of water to adjacent wetlands. However, this option would not allow the area to return to a natural appear- ing and functioning condition. • Restore and enhance the existing wetland sys- tem. This could be done by restoring a complex sys • t em of braided stream and swale features, re- establish t = Balance ing the mound and swale topography naturally associ- ated with lower Amazon Creek basin, developing shal- The Amazon Creek wetland restoration study is an low ponds, and planting native wetland vegetation with effort by the U.S. Army Corps of Engineers to integrate an emphasis on establishing habitat for rare and threat- multiple objectives into its planning process. ened plant species. In the early 1940s, the Corps built Fern Ridge Reser- • Build water quality retention ponds. Two re- voir in response to flooding problems in the Willamette tention ponds are being considered as a part of the Valley. In 1959, the Corps completed a flood control project overall landscape design. The ponds would pretreat wa along Amazon Creek consisting of approximately eight miles ter flows before release into natural wetland areas. of concrete and earthen channels and a 3.8- mile -long di- • Include the Amazon Creek bicycle path in the version canal emptying into Fern Ridge Reservoir. overall design of the project as appropriate. The bike The channelization of the Amazon Creek system has path would follow along the north side of Amazon affected the natural environment. Designed to provide flood Creek from west Eugene to Fern Ridge Lake. control, these projects reduced the water supply to natural An interagency advisory committee has reviewed wetlands, diminished the regular flooding that provided wa the draft study, and the Corps has published its find- ter and nutrients to the wetlands, and drained adjacent wet- ings and recommendations in a report titled Amazon and areas. Furthermore, increased flood security allowed Creek: Environmental Restoration and Reconnaissance Study. for a more intensive level of agricultural and industrial de In the next phase, the Army Corps of Engineers velopment to occur in the area. The net result has been the and the City of Eugene will consider the feasibility of loss of significant wetlands and ash forest that provided proceeding with various options. ea habitat for many endangered and threatened plant species.