the de-”reclamation” of glen canyon · true reclamation: the de-”reclamation” of glen...
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True Reclamation:The De-”Reclamation” of Glen Canyon & the Submerged Ecosystems of Lake Powell
Eric Haley
LA 602 | Jessica HallWinter 2012
Outline » intro » problem statement » goals & objectives » history » geographic context » before the dam » stream�ows » sediment » revegetation » the dam
True Reclamation:The De-”Reclamation” of Glen Canyon & the Submerged Ecosystems of Lake Powell
(Cathedral in the Desert rmrv.com) (Glen Canyon Dam simulated �ood, 2008 Bureau of Reclamation)
(Lake Powell low levels in 2005 NRDC)
Problem statement:
Glen Canyon Dam and its reservoir, 186 mile long Lake Powell, are harmful and unnecessary relics of a past paradigm in water management in the west. Sediment impoundment, an artificial �ow regime with drastically reduced �ood events and daily �uc-tuations, cold temperatures of released water, water loss to evaporation and seepage, and the inundation of archaeological and natural wonders, are all factors that point to the importance of the removal of Glen Canyon Dam and the draining of Lake Powell. However, pollution that has accumulated in the lakebed sediment over the last 50 years, requires more than just removal of the dam to repair the �ooded ecosystems and those downstream in the Grand Canyon.
I am proposing a phased phytoremediation to habitat restoration revegetation program in tandem with lake draw-down, as well as incorporation of the existing monumental structure of the dam itself to a new international eco-tourism destination.
Goals:
» Rehabilitate Glen Canyon to a functioning riparian ecosystem » Maintain or improve contingent social and economic vitality
Objectives:
» Restore predam �ows » Remediate polluted sediment » Restore native vegetation and habitat » Improve recreational programming » Foster ecosystem stewardship
History:
» Colorado Compact of 1922 » Lee’s Ferry » Lower basin: 7.5 million acre-feet/year • California, Nevada, Arizona » Upper basin: 7.5 million acre-feet/year • Wyoming, Utah, Colorado, New Mexico
» Glen Canyon Dam construction: 1956-1963 » Lake Powell reaches its crest in 1980
(back of Glen Canyon Dam during construction, 1963 explorepdx.com)(co�er dam during construction, 1959 explorepdx.com) (dam construction, 1963 explorepdx.com)
Upper Colorado River Basin
Lower Colorado River Basin
Salton Sink
Lake Powell
Los Angeles
Las Vegas
Phoenix
Colorado River Watershed
Glen Canyon Dam
Lee’s Ferry
PageARIZONA
UTAH
Watershed context
UTAH
ARIZONA
Lake Powell
Capitol ReefNational Park
Grand CanyonNational Park
~63 miles
CanyonlandsNational Park
~30 miles
Glen Canyon National Recreation Area
Lee’s Ferry, AZ
Page, AZ
Glen Canyon Dam
Navajo Generating Station
San Juan Arm
approxim
ately
186 river m
iles
Before the damupper reaches
Hite ferry
Cedar Canyon
Tapestry Wall
The Horn
White Canyon
Anasazi Ruins
Anasazi Ruins
Before the dammiddle reaches
Cottonwood Gulch
Mystery Canyon
Ecalante Con�uence
Beaver Canyon
UTAH
ARIZONA
Before the damlower reaches
Dungeon CanyonFace Canyon
Cat�sh Canyon
Cathedral in the Desert
Streamflows over the last 100 years above average misleading for water mgmt 15.2 mil acre-ft avg from 1905-95 14.6 mil acre-ft avg over last 500 yrs
2000-2004 drought 8 similar droughts over the last 500 yrs not the worst of it either
Misunderstood stream�ows
Water input vs. output
loss to evaporation:~430,000 acre-ft/yr
loss to seepage:~430,000 acre-ft/yr
avg. annual input:15,063 cfs
avg. annual output:13,378 cfs
(sediment deposition at Hite, Lake Powell, 2005 nps.gov)
Sediment input vs. output
» between 27,000 and 85,400 acre-feet/year input • about 30,000 dump truck loads per day » could �ll entire lake in as little as 316 years » all of it is trapped in the Lake » sediment is needed downstream for habitat » sediment is polluted • uranium • selenium • arsenic • mercury • petroleum by products
Sediment study area
UTAH
ARIZONA
Sediment measurement
(data source: NCALM; James P. Evans, Utah State University 2005)
Imagery compiled from 1.31-meter-resolution LiDAR-generated (Light Detection And Ranging) DEMs (Digital Elevation Models)
0 1 mile
(data source: NCALM; James P. Evans, Utah State University 2005; USGS 1952)
Sediment measurement
0 1 mile
LiDAR imagery overlay on 1952 topographic map (before Lake Powell)
(data source: NCALM; James P. Evans, Utah State University 2005; USGS 1952; Bureau of Reclamation 1986)
Sediment measurement
0 1 mile
Sample river cross-sections aligned with Bureau of Reclamation reference sections from a 1986 bathymetric survey
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Section300
Section801
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distance (meters)
elev
atio
n (m
eter
s)Section 286
2005 LiDAR1952 USGS surveyLake Powell full pool(1127.76 m = 3700’)
Sediment depth: 33.4m (~110ft)
Historic river channel
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distance (meters)
elev
atio
n (m
eter
s)Section 300
2005 LiDAR1952 USGS surveyLake Powell full pool(1127.76 m = 3700’)
Sediment depth: 47.82m (~157ft)
Historic river channel
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distance (meters)
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Lake Powell full pool(1127.76 m = 3700’)
Section 801 - Mouth of the Dirty Devil River
2005 LiDAR1952 USGS survey
Sediment depth: 41.8 m (~137ft)
Historic river channel (Dirty Devil River)
Sediment storage
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distance (kilometers)
elev
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eter
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San Juan River
Escalante River
Bull Frog Bay
Good Hope Bay
Hite Marina
Dark Canyon
Dirty Devil River
Rainbow Bridge
Last Chance Bay
2005 lowest lake level(1083.6 m = 3555.1’)
Current lake level(1107.9 m = 3634.9’)
Lake Powell full pool(1127.76 m = 3700’)
(data source: Bureau of Reclamation 1986)
Sediment mobilization
» 2004-2005 • approximately 22 years of sediment removed by erosion and subsidence
Dirty Devil River
Colorado River
(data source: NCALM; James P. Evans, Utah State University 2005)
(Google Earth, image date: August 2, 2004)
UTAH
ARIZONA
Revegetation study area
Revegetation study area
» bathymetry = underwater topography
Historic Colorado River Channel
Historic Colorado River Channel
Red Canyon
Revegetation study area
» slopes identi�ed
Historic Colorado River Channel
Historic Colorado River Channel
> 50% slope
33% - 50% slope
16% - 32% slope
8% - 15% slope
< 8% slope
Red Canyon
maximum lake level
Revegetation study area
» priority phytoremediation areas • Amaranth spp. for uranium • Populus cultivars & Opuntia �cus-indica for selenium • Pteris vittata for arsenic
Historic Colorado River Channel
Historic Colorado River Channel
Red Canyon
2004 lake level
Revegetation study area
Historic Colorado River Channel
Historic Colorado River Channel
Red Canyon
Revegetation timeline
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time (years)
expo
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eter
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bottom of Good Hope Bay exposed,power plant no longer operational
“dead pool,” lowest dam intake structures reached
full pool level
historic river gradient elevationat the base of Glen Canyon Dam
remediation plantings for sediment pollution control
native plantings for habitat rehabilitation
begin water and sediment pumping and excavation from behind dam
begin reopeningof diversion tunnels
Glen Canyon Dam eco-engineering
UTAH
ARIZONA
Glen Canyon Dam
Page, Arizona
the dam
access tunnel
Dam plan
East spillway outlet
Historic river banks
East spillway intake(3470’)
West spillway intake(3470’)
Glen Canyon Dam
Glen Canyon Bridge
3715’(Dam crest)
3132’(Historicriver surface)
3700’(Full pool)
3832’(Bridge deck)
Lake Powell
Jet-tube outlets
Colorado River
Power Plant
Grass lawn
West spillway outlet
Visitor Center
Hwy 89
Full pool outline
A A’
Dam plan
East spillway outlet
Historic river banks
East spillway intake(3470’)
West spillway intake(3470’)
Glen Canyon Dam
Glen Canyon Bridge
3715’(Dam crest)
3132’(Historicriver surface)
3700’(Full pool)
3832’(Bridge deck)
Lake Powell
Vehicle access tunnel
East diversion tunnel intake
Jet-tube outlets
Colorado River
Power Plant
Grass lawn
West spillway outlet
Visitor Center
West diversiontunnel intake
Hwy 89
Full pool outline
Dam section/elevation south
AA’
Gantry crane
Top of penstock tower
Glen Canyon Dam
Dam foundation outline
Powerplant
Powerplant outlets
Jet-tube outlets
East spillway tunnel
West spillway tunnel
Estimated river bottom
view of intake structures on upstream side of dam(Bureau of Reclamation 1999)
Jet tube intake
Penstock intake
Dam detour » reopen existing diversion tunnels » expand and lower west tunnel to recreate historic river channel gradient » the dam remains as an artifact and tourist destination