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species utilizing the site
site description
issuesagriculturecontaminationated runoff from adjacent agriculture fields
habitat fragmentationoxbow lake area, CCA and CNWR are disconnected
low quality habitatlimited plant diversityinvasive plant species
opportunities
Palo Verde Oxbow Lake is located in the Lower Colorado River basin, south of Palo Verde.
The lake used to be an old river meander which was cut off in 1967 during the Colorado river diversion. The channel with a seeping water source was left to mitigate wildlife habitat.
The project area consists of the old river channel, the ‘island’ between the lake and the river. It expands to the Cibola Conservation Area to the east and the Cibola NWR to the south.
Cibola Multi-Species Conservation Program boundary
Cibola Valley Conservation Area
Cibola National Wildlife Refuge
project site
connected area
legend
78
C o l o r a d o R
i ve r
proximity to important ecological areas
topography allows to be flooded
location and existing conditions allow to store and control entering water
better conditionscan be provided for interior habitat due to the island’s nature
Oxbow Lake
Oxbow Lake Area
Cibola National Wildlife Refuge
Cibola Valley Conservation Area
oxbow lake campground
the colorado river
oxbow lake
dirt road by oxbow lake
Reach Scale ConceptConnect Oxbow Lake Area with Cibola Valley Conservation Area and Cibola NWRExtend Cibola NWR habitat areaEnhance Cibola Valley Conservation Area by applying ‘natural’ pattern to native species planted areasRemove agriculture fields from the island
C o l or a d o R
i v e r
L e v e e R o a d
campground
bridge
bullrush, phragmitis
tamarisk, screwbean mesquite, honey mesquite
barren land
agriculture field (alfalfa, cotton, small grain)
willow, cottonwood
project boundary
lake
legend
Palo Verde County Park
0 1000’
Hot Spot on the River
Sonoran Yellow Warbler Dendroica petechia sonorana
Southwestern Willow FlycatcherEmpidonax traillii extimus
saturated peat stores water bacteria break down contaminants
provides critical wildlife habitat
provides soil organic matter for the aquatic food chain
oxbow ecology
GoalTo improve existing habitats by reducing habitat fragmentation in Cibola Valley and establishing productive and diverse native plant communities at Palo Verde Oxbow Lake area.
B
B’
barren la
nd
bullrush
, phragmitis
agricultu
re field
(alfalfa
, cotto
n, small g
rain)
tamarisk, sc
rewbean mesq
uite,
honey mesq
uite
willow
228’
235’
228’
237’
MSCP Species utilizing the site
oxbow lake cross-sectionexisting condition
Oxbow Lake
oxbow lake cross-sectionproposed elevation
(height exaggeration 30x)
(height exaggeration 30x)
Flo
od
pla
in
Lo
w F
loo
d T
err
ac
e
Hig
h F
loo
d T
err
ac
e
Colo
rado
Riv
er
Oxb
ow L
ake
Colo
rado
Riv
er
flood levels
Oxb
ow L
ake
bullr
ush,
phr
agm
itis
tam
aris
k, s
crew
bean
mes
quite
, ho
ney
mes
quite
barr
en la
nd Hot Spot on the River
MSCP Targeted Species (riparian obligates)
F l oo d p l a
i n
L o w F
l oo d T
e r r a c eH i g
h Fl o
o d Te r r a c e
Oxbow Lake
B e r m
Stop LogA
A’
Sonoran Yellow Warbler Dendroica petechia sonorana
Southwestern Willow FlycatcherEmpidonax traillii extimus
Arizona Bell's Vireo
Elf Owl
Gila Woodpecker
Yellow-Billed Cuckoo
Vermilion Flycatcher
Summer Tanager
McNeill's Sootywing (breeding)
Yuma clapper rail
California Leaf-Nosed Bat (foraging)
agriculture field (alfalfa, cotton, small grain)
Phase 2
Once native plant communities are estblished the site will offer new oppprtunities for ecological tourism.
Area will be designated as non-motor (silent) zone.RV campgrounds will be transformed into walk-in campgroundsTrails and raised walkways (for high water seasons) will be constructed throughout the site to provide less intrusive observation.
Phase 1Periodic flows will be introduced to the project area and controlled by the site topography and stop-log structure.The flows will temporarily inundate the channel and and floodplain supporting the native plant communities.
Site Scale Design Concept