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