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Western Plateau Planning Area Environmental Conditions - Protected Areas and Managed Waters

Click to view Figure 6.0-14

Figure 6.0-14 Federally Protected Areas in the Western Plateau Planning Area

Protected Areas

The Western Plateau Planning Area has the greatest acreage of federally protected areas as parks, monuments, recreation areas and wilderness areas of any planning area.  It contains almost all of Grand Canyon National Park, three national monuments and small parts of two national recreation areas. In total there are 2.68 million acres of protected federal lands in the planning area, accounting for 31% of the land area.  The Grand Canyon and Grand Canyon-Parashant National Monument make up most of the total with more than two million combined acres. 

Nine wilderness areas are entirely within the planning area as well as part of two others (see Figure 6.0-14).  Wilderness Areas are designated under the 1964 Wilderness Act to preserve and protect the designated area in its natural condition.  Designated areas, their size, basin location and a brief description of the area are listed in Table 6.0-3.  Five wilderness areas are within the boundaries of national monuments. 

Grand Canyon National Park, a World Heritage Site, encompasses 1,218,375 acres.  It was given Federal protection in 1893 as a Forest Reserve and later as a National Monument, and achieved National Park status in 1919.  It receives almost five million visitors each year.   Water for both the North and South Rims of the Park come from Roaring Springs, located 3,000 feet below the North Rim, and transported via pipeline to both rims (see Section 6.0.7) (USBOR, 2002).  Park lands exist in every groundwater basin except the Virgin River and Paria basins, stretching from the confluence of the Little Colorado and Colorado Rivers west to Lake Mead. (See land ownership maps in the basin sections).

The Grand Canyon is of great geologic significance, with a record of three of the four eras of geological time, a rich and diverse fossil record, a huge variety of geologic features and rock types, and numerous caves containing extensive geological, paleontological, archeological and biological resources.  Incised by the Colorado River, the Canyon is considered one of the finest examples of arid-land erosion in the world, averaging 4,000 feet deep for its entire 277 miles (NPS, 2005).

The Park also serves as an ecological refuge, with relatively undisturbed remnants of dwindling ecosystems, including desert riparian communities.  It is home to numerous rare, endemic, and federally protected plant and animal species (NPS, 2007). Construction and operation of Glen Canyon Dam has significantly altered Colorado River flows and sediment deposition, wildlife and habitat along the river in Grand Canyon National Park. A number of studies and actions have been taken and are underway to manage releases from the dam to protect the Park’s resources and to mitigate the impact of dam operations (see “Managed Waters” below).

The Grand Canyon-Parashant National Monument was created by Presidential Proclamation in January 2000.  At 1.05 million acres, it is described in the Proclamation as a geological treasure and as a “vast, biologically diverse, impressive landscape…” The physical remoteness of the monument has helped preserve important biological and archeological resources.  The monument encompasses the lower portion of the Shivwits Plateau Basin, considered an important watershed for the Colorado River and the Grand Canyon, almost all of Grand Wash Basin and a small area north of Toroweap in the Kanab Plateau Basin (USDOI, 2007).  The Monument is jointly administered by the National Park Service (NPS), (211,100 acres) and the Bureau of Land Management (BLM), (808,727 acres).  

Colorado River through the Grand Canyon

Colorado River through the Grand Canyon

Vermilion Cliffs

Vermilion Cliffs

In November 2000, President Clinton also established the Vermilion Cliffs National Monument by proclamation. Encompassing 294,000 acres, the entire monument is within Arizona.  Most of the Paria Plateau Basin and adjoining lands in the Kanab Plateau Basin are within the monument boundaries.  The monument was established to protect geologic features including the 2,500-foot deep Paria Canyon, the Paria Plateau, the spectacular cross-bedded sandstones at Coyote Buttes and the 3,000-foot Vermilion Cliffs escarpment, the Arizona release site of the endangered California condor.

The Arizona Strip Proposed Plan/Final Environmental Impact Statement (FEIS), released in March 2007, serves multiple functions.  It is a revised Resource Management Plan for the Arizona Strip Field Office of the BLM, a new management plan for the Vermilion Cliffs National Monument and a new management plan for the Grand Canyon-Parashant National Monument. It is also a Proposed General Management Plan/Final EIS for the NPS portion of the Grand Canyon-Parashant National Monument, since that monument is jointly administered by the BLM and NPS.

The Proposed Plan/FEIS describes and analyzes five alternatives for managing over 3.3 million acres of lands.  Major issues include management of access and management of areas having wilderness characteristics, protection of natural and cultural resources, management of livestock grazing, and recreation (BLM, 2007). Three final management plans and four records of decision signed by the BLM and NPS were completed in 2008.  Both national monuments are withdrawn from mineral entry while grazing is allowed with adjustments to meet management objectives. Further evaluation of routes in the entire area will continue for several years (USDOI, 2007).

Pipe Spring National Monument, established in 1923, is located in the Kanab Plateau Basin south of Kaibab and Moccasin.  It is a cultural park occupied by several cultures over a period of about 2,000 years due to the occurrence of springs, which have supported farming and ranching activities.  There are four springs within the monument boundaries: West Cabin, Main, Spring Room and Tunnel.  Main Spring and Spring Room have man-made discharge points constructed by Mormon pioneers and are believed to represent the flow of the original natural spring known as Pipe Spring.  Since 1976, NPS staff has measured spring discharge on a monthly basis due to concerns about declines in discharge rates (Truini and others, 2004).

Pipe Springs National Monument

Pipe Spring National Monument Visitor Center

About 3% of the 1.2 million-acre Glen Canyon National Recreation Area is located in the northeastern corner of the Paria Basin.  The Recreation area was created by Congress in 1972 to provide for recreational use of Lake Powell and adjacent lands and to preserve scenic, scientific, and historic features.  It surrounds and includes Lake Powell from Lees Ferry to the Orange Cliffs in Utah.  The principal recreation area development within the planning area is Wahweap, which includes a marina, campground and visitor center.  Fluctuations in the lake level affect recreational activities.  Since designation of the Grand Canyon-Parashant National Monument, the only remaining portion of the Lake Mead National Recreation Area in the planning area is Lake Mead itself.

Glen Canyon Dam

Glen Canyon Dam.  The flow regime of the Colorado River is governed by the Record of Decision for the Glen Canyon Dam EIS and the Glen Canyon Operating Criteria

Managed Waters

The Colorado River is among the most managed rivers in the United States.  The river is impounded behind Glen Canyon Dam, which is managed for both electrical generation purposes and to store water to meet flow obligations at Lees Ferry under the terms of the 1922 Colorado River Compact.  As a result, the river’s flow and the ecosystem it supports have been fundamentally altered.  The Colorado River was a warm, sediment-laden river that historically carried a daily average of 275,000 tons of sediment through the Grand Canyon.  Water temperature varied through the year and large spring floods and varying flow patterns deposited sediment along the riverbanks and provided habitat, including calm spawning pools, for a number of native fish species.  Operation of the dam for electrical generation requires large water releases during historically low flow seasons with daily and weekly fluctuations.  The flow regime is governed by the Record of Decision for the Glen Canyon Dam EIS and the Glen Canyon Operating Criteria (see section 6.0.2). The water released from the bottom of the reservoir is now consistently cold year round and considerably less sediment is now carried downstream, impacting beach building along the riverbank.  Vegetative communities, wildlife and native fish have been affected by the modified river flow (Tellman and others, 1997).  The Colorado pike minnow and bonytail chub no longer occur in the Grand Canyon, and the humpback chub and razorback sucker are listed as endangered species.

Beginning in 1982, the Bureau of Reclamation initiated the multi-agency interdisciplinary Glen Canyon Dam Environmental Studies to evaluate the impact of Glen Canyon Dam and how its operation could be modified to address wildlife and recreational values downstream of the dam.  In 1989, work on an EIS began to consider options for the operation of the dam.  The EIS was completed in 1995 and findings indicated that there were a number of uncertainties regarding the downstream impact of water releases from the Dam.  While the EIS was being developed, Congress passed the Grand Canyon Protection Act (Act) of 1992 (Public Law 102-575), which required operation of the dam in a manner that would protect and mitigate adverse impacts to Grand Canyon National Park and Glen Canyon National Recreation Area.  In compliance with this Act, the EIS proposed an adaptive management process to monitor and assess the effects of dam operations on downstream resources. (USBOR, 2007a)

In 1997, Secretary of Interior (Secretary), Bruce Babbitt, established an Adaptive Management Program (AMP) to “provide an organization and process for cooperative integration of dam operations, downstream resource protection and management, and monitoring and research information…”.  Critical to the program is the Glen Canyon Adaptive Management Work Group (AMWG), a federal advisory committee.  The AMWG incorporates stakeholders into the decision-making process and makes recommendations to the Secretary on how to protect resources.  The group completed a draft strategic plan in 2001 and current focus includes recovery of humpback chub, management of sediment resources and experimental releases of water from Glen Canyon Dam (USBOR, 2007a). Before release of the EIS, the Secretary authorized an artificial flood in the Grand Canyon that would mimic historic spring flows, in order to help build beaches and habitat.  The flood temporarily restored beaches and improved backwater habitat, but pre-flood conditions quickly returned.

As part of the AMP effort, the Bureau of Reclamation completed a scoping report in March 2007 for the Glen Canyon Dam Long-term Experimental Plan EIS. The proposed plan would implement a long-term program in the Colorado River below the dam that could potentially involve dam operations, modifications to the dam’s intake structures and other management actions such as removal of non-native fish (USBOR, 2007a).

Unlike the Colorado River, the Virgin River flows uninterrupted from its headwaters above Zion National Park to Lake Mead. Water is diverted from the Virgin River for municipal and agricultural needs in Utah and for agricultural use in Arizona.  This river, particularly its upper reaches, is recognized for its recreational and scenic values.  Segments of the Virgin River and a number of tributaries totaling 165 miles within Zion National Park were added to the Federal Wild and Scenic River System in March, 2009.  It is the only designated system in Utah.  Congress adopted the Wild and Scenic Rivers Act in October 1968 to preserve selected rivers that possess “outstandingly remarkable scenic, recreational, geologic, fish and wildlife, historic, cultural or other similar values” in their free-flowing condition for the benefit of present and future generations.  Under the Act the river area must be managed in a manner that protects and enhances its “outstandingly remarkable values” (NWSR, 2007).

Virgin River

Virgin River near Scenic.  Unlike the Colorado River, the Virgin River flows uninterrupted from its headwaters above Zion National Park to Lake Mead.



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