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Northern Integrated Supply Project
Supplemental Draft Environmental Impact
Statement
Species of Concern Technical Report
Supplement
Prepared for:
U.S. Army Corps of Engineers
Omaha District
March 2015
Prepared by:
ERO Resources Corporation
1842 Clarkson Street
Denver, Colorado 80218
(303) 830-1188
CONTENTS
1. Introduction .................................................................................................................1
1.1. Changes to the Alternatives since the DEIS ......................................................2
1.1.1. Alternative 1 (No Action Alternative) ...................................................3
1.1.2. Alternative 2 (Proposed Action) ............................................................3
1.1.3. Alternative 3...........................................................................................4
1.1.4. Alternative 4...........................................................................................4
1.2. Poudre River Hydrologic Modeling...................................................................5
2. Study Areas .................................................................................................................5
2.1. Study Areas Unchanged from the DEIS ............................................................5
2.2. No Action Alternative Study Area .....................................................................5
2.3. U.S. 287 Realignment Study Area .....................................................................5
2.4. Galeton Reservoir and SPWCP Study Area ......................................................6
2.5. Cactus Hill Reservoir and SPWCP Study Areas ...............................................6
3. Regulatory Framework ...............................................................................................6
4. Methods.......................................................................................................................7
5. Ecological Setting .......................................................................................................9
5.1. Federally Listed Threatened, Endangered, and Candidate Species ...................9
5.1.1. Species with No Potential Habitat in the Study Areas .........................10
5.2. State Species of Concern .................................................................................13
6. Results .......................................................................................................................17
6.1. Flow-related Indirect Effects Common to All Alternatives (No Action
and Action Alternatives) ..................................................................................17
6.1.1. Effects on Species of Concern from Changes to Wetland and
Riparian Vegetation on the Mainstem .................................................17
6.2. Effects of No Action Alternative (Alternative 1) ............................................20
6.2.1. Federally Listed Threatened, Endangered, and Candidate
Species .................................................................................................22
6.2.2. State Species of Concern .....................................................................23
6.3. Direct and Indirect Effects Common to All Action Alternatives ....................27
6.4. Alternative 2 – (Applicant’s Preferred) Glade Reservoir and the
SPWCP ............................................................................................................27
6.4.1. Federally Listed Threatened, Endangered, and Candidate
Species .................................................................................................28
6.4.2. State Species of Concern .....................................................................29
6.5. Alternative 3 – Cactus Hill Reservoir, Poudre Valley Canal Diversion,
and the SPWCP ................................................................................................33
6.5.1. Federally Listed Threatened, Endangered, and Candidate
Species .................................................................................................34
6.5.2. State Species of Concern .....................................................................35
6.6. Alternative 4 – Cactus Hill Reservoir, Multiple Diversion Locations,
and the SPWCP ................................................................................................38
i
6.6.1. Federally Listed Threatened, Endangered, and Candidate
Species .................................................................................................39
6.6.2. State Species of Concern .....................................................................40
7. Summary ...................................................................................................................43
8. References .................................................................................................................50
TABLES
Table 1. Federally-listed Threatened, Endangered, and Candidate Species
Potentially occurring in the Study Areas or Potentially Affected by
the Project and their Habitat Ratings. ...........................................................11
Table 2. State-listed Threatened, Endangered, and Candidate Species; and
CNHP Sensitive Species Potentially occurring in the Study Areas..............14
Table 3. Direct and Indirect Effects (Acres of Habitat) of the No Action
Alternative (Alternative 1) on Species of Concern. ......................................20
Table 4. Direct Effects (Acres of Habitat) of Alternative 2 on Species of
Concern. ........................................................................................................28
Table 5. Direct Effects (Acres of Habitat) of Alternative 3 on Species of
Concern. ........................................................................................................33
Table 6. Direct Effects (Acres of Habitat) of Alternative 4 on Species of
Concern. ........................................................................................................38
Table 7. Summary of Effects on Species of Concern from the NISP
Alternatives. ..................................................................................................44
FIGURES
Figure 1. No Action Alternative
Figure 2. Alternative 2 - Glade Reservoir and the SPWCP (District’s Preferred
Alternative)
Figure 3. Alternative 3 - Cactus Hill Reservoir, Poudre Valley Canal
Diversion, and the SPWCP
Figure 4. Alternative 4 - Cactus Hill Reservoir, Multiple Diversion Locations,
and the SPWCP
Figure 5. Species of Concern Habitat in the Study Areas
Figure 6. Species of Concern Habitat at Glade Reservoir, U.S. 287, and
Pipeline Study Areas
Figure 7. Location of Bell’s Twinpod at U.S. 287 Study Area
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ENVIRONMENTAL IMPACT STATEMENT
SPECIES OF CONCERN TECHNICAL REPORT SUPPLEMENT
1. INTRODUCTION
The U.S. Army Corps of Engineers (Corps) prepared a draft environmental impact
statement (DEIS) for the proposed Northern Integrated Supply Project (NISP) in
April 2008. Subsequent to the draft EIS, the Corps made a decision to provide a
supplemental draft EIS (SDEIS) that provides additional information and analysis on
specific issues and resources. This Species of Concern Technical Report Supplement is
being updated based on changes to federal and state listed species and species listed as
rare, vulnerable, and imperiled by the Colorado Natural Heritage Program (CNHP),
changes to the NISP alternatives since the DEIS was published, and revised hydrologic
modeling for the Poudre River. The operations, components, and pipeline alignments of
the No Action Alternative, also referred to as Alternative 1, and the three action
alternatives are shown in Figure 1 through Figure 4 and are described in the Hydrologic
Modeling Report (CDM Smith and DiNatale 2013).
Comments received on the DEIS related to species of concern pertained mainly to
concerns about Preble’s meadow jumping mouse, Ute ladies’-tresses orchid, and
Colorado butterfly plant, three federally listed species. At the time of the release of the
DEIS, the Corps had completed consultation with the U.S. Fish and Wildlife Service
(USFWS) under Section 7 of the Endangered Species Act regarding effects on threatened
or endangered species from the Proposed Action, and the USFWS had issued a Biological
Opinion based on the effects described in the Biological Assessment. Since the release of
the DEIS, changes have been made to the Proposed Action, and depending on predicted
project effects and comments received on the SDEIS, additional changes may be made to
the Proposed Action after the closure of the SDEIS public comment period. The Corps
will prepare a Supplemental Biological Assessment that addresses changes to the
Proposed Action that could have effects on federally listed threatened or endangered
species and will reinitiate consultation with the USFWS as required by the ESA. These
actions will take place prior to issuance of the FEIS or a Record of Decision.
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SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT
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The information in this technical report replaces Sections 1.2, 1.8, 1.9, 1.10, 2.1, 2.3,
6.1, and 6.5 and updates Sections 2.4, 2.5, 4, 6.2, 6.3, and 6.4 of the 2008 Species of
Concern Technical Report (2008 Species of Concern Report; ERO 2008). The
information in this technical report will be summarized in the SDEIS and final EIS. This
report does not address cumulative effects or mitigation measures for species of concern.
Cumulative effects and mitigation will be addressed in the SDEIS. Aquatic resources are
discussed in the Aquatic Biological Resources Baseline Report for the Mainstem Cache
la Poudre and South Platte River (GEI 2013) and the Aquatic Biological Resources
Effects Technical Report (GEI 2014).
1.1. Changes to the Alternatives since the DEIS
Changes to the alternatives since the DEIS that would affect species of concern
include development of a new no action alternative, changes to the capacities of the
proposed Galeton and Cactus Hill reservoirs, changes to the pipeline alignments, changes
in proposed operations under Alternative 2, elimination of an action alternative
(Alternative 4 in the DEIS), and development of a new action alternative (Alternative 4 in
the SDEIS).
The following major changes have been made to the alternatives subsequent to the
DEIS:
SDEIS No Action Alternative – A new no action alternative that includes
storage in the existing Big Windsor Reservoir, Lonetree Reservoir, and the
proposed Cactus Hill Reservoir and the transfer of water from 64,200 acres of
irrigated land in the Larimer-Weld, New Cache, and Home Supply irrigation
systems to municipal use is analyzed in detail in the SDEIS.
DEIS Alternative 4 Not Carried Forward – Alternative 4 – Glade or Cactus
Hill Reservoirs and South Platte Water Conservation Project (SPWCP) with
Agricultural Transfers was eliminated and not carried forward for detailed
evaluation in the SDEIS. The new no action alternative for the SDEIS includes
agricultural transfers.
SDEIS Alternative 4 – A new action alternative that includes the proposed
Cactus Hill Reservoir and SPWCP with diversions from the Poudre River at the
Poudre Valley Canal and New Cache Canal headgate was analyzed in detail in the
SDEIS.
Preferred Realignment of U.S. 287 – The Colorado Department of
Transportation (CDOT) selected the western alignment as their preferred
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SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT
SPECIES OF CONCERN TECHNICAL REPORT SUPPLEMENT
alternative for the realignment of U.S. 287 associated with Alternative 2. The
northern alignment was not carried forward in the SDEIS.
The following changes to the proposed NISP facilities that may have direct effects on
species of concern have been made subsequent to the DEIS:
Galeton Reservoir Size – Galeton Reservoir was sized at 40,000 acre-feet (AF)
in the DEIS. Galeton Reservoir is now proposed to be expanded to 45,624 AF.
The high water elevation of Galeton Reservoir would change from 4,869 feet to
4,872 feet. The surface area would change from 1,881 acres to 2,010 acres.
Cactus Hill Reservoir Size – Cactus Hill Reservoir has been expanded from
180,000 AF as presented in the DEIS to 190,000 AF for Alternatives 3 and 4 in
the SDEIS. The expansion of Cactus Hill Reservoir is in response to the new
Common Technical Platform hydrology modeling and its increased evaporation
estimates for Cactus Hill Reservoir. The 190,000-AF size is estimated to provide
the same yield as the 180,000-AF size estimated in the DEIS.
Descriptions of the alternatives proposed for the SDEIS are in the Hydrologic
Modeling Report (CDM Smith and DiNatale 2013). The following key components of
the alternatives proposed for the SDEIS may affect species of concern in the study areas.
1.1.1. Alternative 1 (No Action Alternative)
Transfer of water from 64,200 acres of irrigated land in the Larimer-Weld, New
Cache, and Home Supply irrigation systems to municipal use
Storage of water in the existing Big Windsor Reservoir, Lonetree Reservoir, and a
new 120,000-AF Cactus Hill Reservoir
Construction of two new regional water treatment plants
Construction of 121 miles of water pipelines and nine pumping stations
Realignment of three 2-lane Weld County roads totaling 10.3 miles
Realignment of 6.8 miles of a 230-kV electric transmission line owned by Platte
River Power Authority
1.1.2. Alternative 2 (Proposed Action)
Diversion from the Poudre River at the Poudre Valley Canal for the Northern
Colorado Water Conservancy District’s (District) Grey Mountain water right;
exchanges from the SPWCP; and reservoir exchanges with Terry Lake, Big
Windsor Reservoir, and Timnath Reservoir
Storage of water diverted from the Poudre River in a new 170,000-AF Glade
Reservoir
Augment flows in the Poudre River by releases from a designated 3,600-AF
release pool in Glade Reservoir with a target of maintaining a 10-cubic feet per
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SPECIES OF CONCERN TECHNICAL REPORT SUPPLEMENT
second (cfs) flow below the Larimer-Weld Canal headgate from November
through April and September 1 through September 30
Construction of the SPWCP, which includes the new Galeton Reservoir
Construction of new pumping stations and water pipelines
Realignment of about 7 miles of U.S. 287 near Laporte, Colorado using CDOT’s
preferred western alignment
Realignment of four electrical transmission line structures totaling 0.6 mile of a
69-kV line owned by Poudre Valley REA
1.1.3. Alternative 3
Diversion from the Poudre River at the Poudre Valley Canal for the District’s
Grey Mountain water right; exchanges from the SPWCP; and reservoir exchanges
with Terry Lake, Big Windsor Reservoir, and Timnath Reservoir
Storage of water in a new 190,000-AF (70,000-AF larger than the No Action
Alternative - Alternative 1) Cactus Hill Reservoir
Construction of the SPWCP
Construction of new pumping stations and water pipelines
Realignment of three 2-lane Weld County roads totaling 10.3 miles
Realignment of 6.8 miles of a 230–kV Platte River Power Authority transmission
line
1.1.4. Alternative 4
Diversion from the Poudre River at the Poudre Valley Canal for the District’s
Grey Mountain water right supply; SPWCP exchanges with the Larimer-Weld
Canal; and reservoir exchanges with Terry Lake, Big Windsor Reservoir, and
Timnath Reservoir
Diversion from the Poudre River at the New Cache Canal for the New Cache
exchange water from the SPWCP
Storage of water diverted from the Poudre River in a new 190,000-AF Cactus Hill
Reservoir
Construction of the SPWCP infrastructure, with minor operational changes from
Alternatives 2 and 3 to make NISP exchange diversions from the New Cache
Canal rather than upstream at the Poudre Valley Canal headgate
Construction of new pumping stations and water pipelines
Realignment of three 2-lane Weld County roads totaling 10.3 miles
Realignment of 6.8 miles of a 230-kV Platte River Power Authority transmission
line
4NORTHERN INTEGRATED SUPPLY PROJECT
SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT
SPECIES OF CONCERN TECHNICAL REPORT SUPPLEMENT
1.2. Poudre River Hydrologic Modeling
In addition to changes to the alternatives, an assessment of indirect effects on species
of concern was conducted along the mainstem of the Poudre River (Mainstem). In 2009,
the Corps decided to develop a common technical platform (CTP) for specific resources
that could be affected by NISP and the Halligan Seaman Water Supply Projects
(HSWSPs), as described in the Methods section (Section 4) below and in the Wetlands
and Riparian Resources Effects Technical Report for the Mainstem of the Cache la
Poudre River (ERO 2014). Indirect effects on species of concern along the Poudre River
corridor were updated using the results of the assessment of indirect effects on wetland
and riparian vegetation using the CTP hydrologic modeling (ERO 2014).
2. STUDY AREAS
2.1. Study Areas Unchanged from the DEIS
The study areas for Glade Reservoir, Glade to Horsetooth Pipeline, Carter Pipeline,
Poudre Valley Canal, Poudre River, and South Platte River are described in Section 2.2,
Sections 2.6 through 2.8, and Section 2.11 of the 2008 Species of Concern Report (ERO
2008). The study areas for these project components are unchanged.
2.2. No Action Alternative Study Area
This description of the No Action Alternative study area replaces Section 2.1 of the
2008 Species of Concern Report (ERO 2008). The exact locations of lands involved in
the transfer of water from agricultural lands are unknown, but it is estimated that about
64,200 acres of irrigated agricultural lands in the Larimer-Weld, New Cache, and Home
Supply irrigation systems would be dried up under the No Action Alternative (Figure 1).
The No Action Alternative study area includes the footprint of all of the components
described under the No Action Alternative component section above.
2.3. U.S. 287 Realignment Study Area
This section replaces Section 2.3 of the 2008 Species of Concern Report (ERO 2008).
The 2008 Species of Concern Report (ERO 2008) described two realignment alternative
study areas for U.S. 287. CDOT selected the western alignment as their preferred
alternative for the realignment of U.S. 287 associated with the Proposed Action
(District’s Preferred Alternative). The northern alignment is not included in the SDEIS.
5NORTHERN INTEGRATED SUPPLY PROJECT
SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT
SPECIES OF CONCERN TECHNICAL REPORT SUPPLEMENT
The proposed realignment would begin at the existing U.S. 287 and proceed north
through the reclaimed Holcim Mine.
2.4. Galeton Reservoir and SPWCP Study Area
The Galeton Reservoir and SPWCP study area is described in Section 2.4 of the 2008
Species of Concern Report (ERO 2008). Because the proposed storage capacity of
Galeton Reservoir increased from 40,000 AF to 45,264 AF, the study area increased and
habitat types in the new portion of the study area are included in this report. At the time
of field studies for the 2008 Species of Concern Report, the resources were mapped
beyond the reservoir footprint.
2.5. Cactus Hill Reservoir and SPWCP Study Areas
The Cactus Hill Reservoir and SPWCP study areas are described in Section 2.5 of the
2008 Species of Concern Report (ERO 2008). Because the proposed storage capacity of
Cactus Hill Reservoir for Alternatives 3 and 4 increased from 180,000 AF to 190,000 AF,
the study area increased, and habitat types in the new portion of the study area are
included in this report. Alternatives 3 and 4 would also include conveyance pipelines for
delivery of water to and from Cactus Hill Reservoir (Figure 3 and Figure 4).
3. REGULATORY FRAMEWORK
This section updates Section 3 of the 2008 Species of Concern Report (ERO 2008).
The regulatory framework for species of concern in the study areas is unchanged except
that the list of threatened, endangered, proposed, and candidate species potentially
occurring in Larimer and Weld counties has been updated to include the Western prairie
orchid and Arapahoe snowfly (USFWS 2014). These species and their potential to occur
in the study areas are discussed below. In 2007, the bald eagle was de-listed under the
Endangered Species Act (ESA) (72 FR 37346). Currently, the bald eagle does not
receive any protection under the ESA, though it is protected under the Bald and Golden
Eagle Protection Act (BGEPA) and the Migratory Bird Treaty Act (MBTA). The bald
eagle was removed from the Colorado list of threatened and endangered species in 2009
and is currently designated as a Species of Concern, a non-statutory category.
6NORTHERN INTEGRATED SUPPLY PROJECT
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SPECIES OF CONCERN TECHNICAL REPORT SUPPLEMENT
4. METHODS
Methods used to analyze effects on species of concern are described in Section 4 of
the 2008 Species of Concern Report (ERO 2008). Species of concern are federally listed
threatened, endangered, and candidate species; state-listed threatened, endangered, and
species of concern; and species ranked as rare, vulnerable, or imperiled in Colorado by
the Colorado Natural Heritage Program (CNHP ranking S1, S2, or S3). For CNHP-
ranked plant species, only species ranked S1 or S2 are addressed in this report. No
CNHP-ranked S3 species have habitat within the study areas. Plant community types that
meet or potentially meet the description of plant communities listed by the CNHP as
critically imperiled (S1) or imperiled (S2) in Colorado are described in the 2015
Vegetation and Wetland Resources Technical Report Supplement (ERO 2015) and are
not discussed in this report.
The effects analysis for state species of concern includes only species that have been
recently observed in the study areas. As described in the 2008 Species of Concern
Report, the effects analysis for state species of concern includes only those that have been
observed from 2000 to present at the study areas. Three species ranked by the CNHP as
either S1 or S2 have been observed at City of Fort Collins Natural Areas along the Cache
la Poudre (Poudre) River: the smokey-eyed brown butterfly, two-spotted skipper, and
American currant. These species were not observed in the study areas during field
surveys from 2004 to 2006; however, they are included in the discussion of potential
effects of changes in streamflow in the Poudre River because their potential habitat
occurs in riparian areas.
No new field surveys were conducted for species of concern or their habitat for the
SDEIS. Effects calculations were updated for this report based on updates to the
Colorado Parks and Wildlife (CPW) database (CPW 2013), CNHP updates
(CNHP 2014), and changes to the alternatives.
Effects to species of concern are described as negligible, minor, moderate, or major
based on the following criteria. Negligible effects would be at the lowest levels of
detection, barely measurable, with no perceptible consequences. Minor is used when the
impacts would be at low levels and may not have a noticeable effect on species of
7NORTHERN INTEGRATED SUPPLY PROJECT
SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT
SPECIES OF CONCERN TECHNICAL REPORT SUPPLEMENT
concern or their populations. Minor effects include temporary impacts during
construction. Minor effects typically are short-term. Moderate is used when impacts to
species of concern would affect individuals or small groups of species of concern, but
would not affect populations or large areas of habitat. Major is used when impacts to
populations or large areas of species of concern habitat would occur. Major effects
typically are long-term. The term no impact is used when there are no changes to
existing conditions from the alternatives.
Permanent impacts to federally threatened, endangered, and candidate species habitat
could occur in areas that are inundated or permanently filled by project features such as
dam footprints, access roads, and pump stations. Temporary impacts to federal
threatened, endangered, and candidate species habitat could occur in areas that would be
returned to their approximate original contour and vegetation following construction,
such as pipeline routes and staging areas. Potential effects were evaluated for the loss or
disturbance of habitat and potential for affecting species population, viability,
distribution, travel, and reproduction.
Findings on the potential effects on federally listed species were based on the
determination language used by the USFWS (1998). Possible determinations include:
No effect The proposed action would not affect listed species or designated critical
habitat.
Is not likely to adversely affect The effect on listed species is expected to be
discountable, insignificant, or completely beneficial.
Likely to adversely affect The action would have a direct or indirect adverse
effect to listed species as a result of the proposed action, or its interrelated or
interdependent actions; and the effect is not discountable, insignificant, or beneficial.
Direct impacts for the U.S. 287 realignment study area were calculated based on a
100-foot width for permanent surface impacts and 150-foot width for temporary surface
impacts. Permanent impacts associated with the proposed Glade, Galeton, and Cactus
Hill reservoirs include reservoirs, dams, forebays, permanent access roads, and pump
8NORTHERN INTEGRATED SUPPLY PROJECT
SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT
SPECIES OF CONCERN TECHNICAL REPORT SUPPLEMENT
stations. A 20-foot disturbance zone is assumed for pipeline impacts, which would be
temporary in most cases.
Potential indirect effects on species of concern in the Poudre River study area were
updated based on revised effects on riparian and wetland vegetation. In coordination
with the U.S. Geological Survey, six representative riparian vegetation study sites were
established on the Mainstem to assess changes in habitat associated with changes in
flows. Wetland and riparian vegetation was mapped at each of the six riparian vegetation
study sites to develop relationships between vegetation, ground water, and streamflows.
Wetland and riparian resources mapping by the Colorado Parks and Wildlife (formerly
Colorado Division of Wildlife) was reviewed and revised for the Poudre River corridor
from the canyon mouth to the confluence with the South Platte River to determine the
distribution of wetland and riparian resources. Data on tree recruitment, distribution of
size classes of trees, wetland functions, and noxious weeds were collected at each of the
six riparian vegetation study sites. Historical aerial photos were reviewed to assess
changes in land use and distribution of riparian communities along the Poudre River.
The new CTP hydrology, stream geomorphology modeling, information on ground
water-streamflow relationships, and woody vegetation recruitment were used to
reevaluate effects on the Mainstem wetland and riparian resources associated with
changes in Poudre River flows and to prepare new technical reports for the SDEIS.
The CTP study included an assessment of the amount of wetlands associated with
irrigation in the region to determine the potential effect on wetlands with the removal of
irrigation (WEST 2010). Additional information on the assessment of riparian and
wetland effects is presented in the Wetlands and Riparian Resources Effects Technical
Report for the Mainstem of the Cache la Poudre River (ERO 2014).
5. ECOLOGICAL SETTING
5.1. Federally Listed Threatened, Endangered, and Candidate Species
This section updates Section 5 of the 2008 Species of Concern Report. Table 1 shows
federally listed threatened, endangered, and candidate species potentially occurring in the
study areas or potentially affected by the project and provides the habitat ratings of these
species within the study areas. Table 1 also shows federally listed species including
9NORTHERN INTEGRATED SUPPLY PROJECT
SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT
SPECIES OF CONCERN TECHNICAL REPORT SUPPLEMENT
whooping crane, least tern, and piping plover, which potentially could be indirectly
affected by continued or ongoing water depletions to the Platte River system in central
Nebraska. These species are discussed under Platte River Species in Section 5.1.8 of the
2008 Species of Concern Report. Table 1 in this report replaces Table 1 from the 2008
Species of Concern Report. Updated species of concern habitat in the NISP study areas
is shown in Figures 5, 6, and 7, which replace Figures 7, 6, and 8, from the 2008 Species
of Concern Report, respectively.
5.1.1. Species with No Potential Habitat in the Study Areas
For federally listed species, only those species with potential habitat in the study areas
were included in the effects analysis. A number of federally listed threatened,
endangered, proposed, or candidate species have the potential to occur in Larimer and
Weld counties but do not have the potential to occur in any of the study areas (Table 1).
Canada lynx, Mexican spotted owl, greater sage grouse, and Arapahoe snowfly are
unlikely to occur in the study areas due to a lack of suitable habitat and there would be no
effect on these species. The habitat requirements of Canada lynx and Mexican spotted
owl and the rationale for excluding the study areas as habitat for these species are
described in Section 5.1 of the 2008 Species of Concern Report (ERO 2008). In
September 2009, the USFWS determined that eastern Colorado, including the entire
NISP study area, no longer contains any wild free-ranging black-footed ferrets and
established a block clearance zone (USFWS 2009). Projects within the block clearance
zone would not adversely affect the black-footed ferret; thus, none of the NISP
alternatives would have an effect on the black-footed ferret. Species affected by
depletions to the South Platte River will be addressed in the Supplemental Biological
Assessment that would be submitted to the USFWS.
10NORTHERN INTEGRATED SUPPLY PROJECT
SUPPLEMENTAL DRAFT ENVIRONMENTAL IMPACT STATEMENT
SPECIES OF CONCERN TECHNICAL REPORT
Table 1. Federally-listed Threatened, Endangered, and Candidate Species Potentially occurring in the Study Areas or Potentially
Affected by the Project and their Habitat Ratings.
Habitat Ratings of Study Areas2
Federal Pipelines
Common Name Scientific Name Habitat U.S. 287 Poudre
Status1 Glade Cactus Hill Galeton and Other
Realignment River
Facilities3
Mammals
Canada lynx Lynx canadensis T Spruce/fir forests 0 0 0 0 0 0
Rangeland and
shortgrass prairie with
Black-footed ferret Mustela nigripes E 0 0 0 0 0 0
large prairie dog
colonies
Preble’s meadow Zapus hudsonius Wetland and riparian
T 3 0 0 0 3 3
jumping mouse preblei areas with shrubs
Birds
Greater sage Centrocercus Sagebrush dominated
C 0 0 0 0 0 0
grouse urophasianus areas
Charadrius Sandy beaches, gravel
Piping plover4 T 0 0 0 0 0 0
melodus bars, and sandy islands
Whooping crane4 Grus americana E Large lakes and rivers 0 0 0 0 0 0
Open grasslands in
Numenious Nebraska and other
Eskimo Curlew4 E 0 0 0 0 0 0
borealis plains states; not found
in Colorado
Sterna Sandy beaches, gravel
Least tern4 E 0 0 0 0 0 0
antillarum bars, and sandy islands
Mexican spotted Strix occidentalis Old growth forests with
T 0 0 0 0 0 0
owl lucida cliffs
Fish
Large, turbid, free-
flowing rivers with a
Scaphirhynchus
Pallid sturgeon4 E strong current and 0 0 0 0 0 0
albus
gravel or sandy
substrate
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SPECIES OF CONCERN TECHNICAL REPORT
Habitat Ratings of Study Areas2
Federal Pipelines
Common Name Scientific Name Habitat U.S. 287 Poudre
Status1 Glade Cactus Hill Galeton and Other
Realignment River
Facilities3
Plants
Gaura
Colorado butterfly
neomexicana T Floodplains 2 1 0 0 2 2
plant
coloradensis
Ute ladies’-tresses Spiranthes Subirrigated floodplains
T 1 1 0 0 2 2
orchid diluvialis and wetlands
Western prairie Platanthera Mesic and wet prairies,
T 0 0 0 0 0 0
fringed orchid5 praeclara sedge meadows
Insects
Known only from two
sites on tributaries to
the Poudre River;
Capnia
Arapahoe snowfly C nymphs require aquatic 0 0 0 0 0 0
arapahoe
habitat and adults
require terrestrial
habitat
Habitat generalist;
known only from a few
American burying Nicrophorus
E locations in the 0 0 0 0 0 0
beetle5 americanus
midwestern United
States
Source: USFWS 2014.
1
T = Threatened, E = Endangered, C = Candidate.
2
Habitat rating: 0 = No habitat; 1 = Limited habitat present, species unlikely to occur; 2 = Potential breeding and foraging habitat for wildlife, and potential habitat for plants;
3 = Known to occur.
3
Pipelines and other facilities include the Glade to Horsetooth Pipeline, Carter Pipeline, Poudre Valley Canal, and pump stations.
4
Water depletions in the South Platte River may affect species or habitat downstream in central Nebraska.
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Arapahoe Snowfly
On May 12, 2012, the USFWS found that listing the Arapahoe snowfly is warranted
but precluded by higher priority listing actions. The Arapahoe snowfly remains a
candidate for listing under the Act. It has only been found in two small tributaries
(Elkhorn Creek and Young Gulch) of the Poudre River. Both sites are on U.S. Forest
Service lands. The species has not been found in Young Gulch since 1986 and may no
longer occur at this site. The nymphs require aquatic habitat, and adults require terrestrial
habitat. The known populations of this species are upstream of the NISP study areas.
The proposed project would have no effect on the Arapahoe snowfly.
Greater Sage Grouse
On March 23, 2010, the USFWS found that listing the greater sage grouse
(rangewide) is warranted but precluded by higher priority listing actions. The greater
sage grouse remains a candidate for listing under the Act. Sage grouse distribution is
closely correlated with sagebrush habitats. Due to a lack of sagebrush habitat in the study
areas, sage grouse are unlikely to occur in the study areas and the proposed project would
have no effect on the greater sage grouse.
5.2. State Species of Concern
State-listed threatened, endangered, and candidate species and CNHP sensitive
species potentially occurring in the study areas are shown in Table 2. Table 2 in this
report replaces Table 2 from the 2008 Species of Concern Report.
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Table 2. State-listed Threatened, Endangered, and Candidate Species; and CNHP Sensitive Species Potentially occurring in the
Study Areas.
Common Name Scientific Name State Status1 CNHP Rank2 Habitat Possible Location3
Mammals
Black-tailed prairie dog Cynomys ludovicianus SC G3/4, S3 Rangeland; shortgrass prairie All
GL, U.S. 287, GL-HT,
Dwarf shrew Sorex nanus G4, S2 Alpine areas to shrubby wooded foothills
CP
GL, U.S. 287, GA, CH,
Swift fox Vulpes velox SC G3, S3 Shortgrass prairie CH-HT, SPWCP,
PVC, AG
GL, U.S. 287, GL-HT,
Townsend’s big-eared bat Plecotus townsendii SC G4, S2 Woodlands with rocky outcrops
CP
Birds
Haliaeetus Trees and cliffs, rivers, large lakes; forages GL, GA, GL-HT,
Bald eagle ST G5, S1/3
leucocephalus in rivers and lakes CLP/SP
Black-necked stilt Himantopus mexicanus G5, S3 Freshwater lakes, ponds, and marshes GL, U.S. 287
Rangeland and shortgrass prairie containing
Burrowing owl Athene cunicularia ST G4, S4 All
prairie dog colonies
GA, CH, CH-HT,
Chestnut-collared longspur Calcarius ornatus G5, S1 Shortgrass prairie
SPWCP, PVC
GL, U.S. 287, GA, CH,
Ferruginous hawk Buteo regalis SC G4, S3 Shortgrass prairie GL-HT, CP, CH-HT,
SPWCP, PVC
GA, CH, CH-HT,
Long-billed curlew Numenius americanus SC G5, S2 Native grassland and shortgrass prairie
SPWCP
GA, CH, CH-HT,
McCown’s longspur Calcarius mccownii G5, S2 Rangeland and shortgrass prairie
SPWCP, PVC
GA, CH, CH-HT,
Mountain plover Charadrius montanus SC G2, S2 Rangeland and shortgrass prairie
SPWCP
Peregrine falcon Falco peregrinus SC G4, S2 Steep cliffs and canyons GL, U.S. 287, GL-HT
Reptiles
GL, U.S. 287, CH, AG,
Thamnophis sirtalis GL-HT, CP, CH-HT,
Common gartersnake SC NI Wetland and riparian areas
parietalis PVC, SPWCP,
CLP/SP
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Common Name Scientific Name State Status1 CNHP Rank2 Habitat Possible Location3
Amphibians
GL, U.S. 287, CH, AG,
GL-HT, CP, CH-HT,
Northern leopard frog Rana pipiens SC G5, S3 Wetlands
PVC, SPWCP,
CLP/SP
Insects
GL, U.S. 287, GL-HT,
Arogos skipper Atrytone arogos G3/4, S2 Grasslands with abundance of big bluestem
CP
Mid-tallgrass prairie with abundance of big GL, U.S. 287, GL-HT,
Dusted skipper Atrytonopsis hianna G4/5, S2
and little bluestem CP
Foothills, canyons usually with abundance
Hops feeding azure Celastrina humulus G2/3, S2 GL, GL-HT, CP
of hops
Steep cliffs and canyons containing yellow
Moss’ elfin Callophrys mossi G3/4, S2/3 GL, U.S. 287
stonecrop
Scrub-oak woodlands with abundance of GL, U.S. 287, GL-HT,
Mottled duskywing Erynnis martialis G3/4, S2/3
buckbrush. CP
Mid-tallgrass prairie with abundance of big GL, U.S. 287, GL-HT,
Ottoe skipper Hesperia ottoe G3/4, S2
bluestem CP
GL, U.S. 287, GL-HT,
Regal fritillary Speyeria idalia G3, S1 Tallgrass prairie
CP, PVC, SPWCP
GL, U.S. 287, GA,
Rhesus skipper Polites rhesus G4, S2/3 Shortgrass prairie dominated by blue grama GH, GL-HT, CP, CH-
HT, SPWCP, PVC
Open pinion-juniper and shortgrass prairie
Simius roadside skipper Amblyscirtes simius G4, S3 GL, GL-HT, CP
dominated by blue grama
GL, U.S. 287, GL-HT,
Smokey-eyed brown Satyrodes eurydice
G5, S1 Tallgrass prairie with abundance of sedges CP, PVC, SPWCP,
butterfly fumosa
CLP/SP
GL, U.S. 287, GL-HT,
Two-spotted skipper Euphyes bimacula G4, S2 Sedge-dominated meadows CP, CH-HT, PVC,
SPWCP, CLP/SP
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Common Name Scientific Name State Status1 CNHP Rank2 Habitat Possible Location3
Plants
Moist woods and riparian woodlands at the
American currant Ribes americanum G5, S2 GL, CLP/SP
base of the foothills
GL, U.S. 287, GL-HT,
Bell’s twinpod Physaria bellii G2, S2 Dry loose shale
CP
Woodlands, stream bank, and riparian GL, U.S. 287, CP,
Lavender hyssop Agastache foeniculum G4/5, S1
habitat within shortgrass prairie CLP/SP
Rocky Mountain sedge Carex saximontana G5, S1 Pine forests, riparian woodlands GL
Source: Colorado Parks and Wildlife 2014.
1
ST = State Threatened, SE = State Endangered, SC = State Species of Special Concern.
2
CNHP Ranks:
G1 = Critically imperiled globally because of extreme rarity (5 or fewer occurrences, or very few remaining individuals), or because of some factor of its biology making it especially
vulnerable to extinction. (Critically endangered throughout its range.)
G2 = Imperiled globally because of rarity (6 to 20 occurrences) or because of other factors demonstrably making it very vulnerable to extinction throughout its range. (Endangered
throughout its range.)
G3 = Vulnerable throughout its range or found locally in a restricted range (21 to 100 occurrences). (Threatened throughout its range.)
G4 = Apparently secure globally, though it might be quite rare in parts of its range, especially at the periphery.
GU = Unable to assign rank due to lack of available information.
S1 = Critically imperiled in state because of extreme rarity (5 or fewer occurrences, or very few remaining individuals), or because of some factor of its biology making it especially
vulnerable to extirpation from the state. (Critically endangered in state.)
S2 = Imperiled in state because of rarity (6 to 20 occurrences) or because of other factors demonstrably making it very vulnerable to extirpation from the state. (Endangered or threatened
in state.)
S3 = Vulnerable in state (21 to 100 occurrences.)
S4 = Apparently secure in the state, though it might be quite rare in parts of its range, especially at the periphery.
SH = Extirpated or extinct from the state.
NI = No information.
T(1-5) = Trinomial Rank – Used for subspecies. These species are ranked on the same criteria as G1 to G5.
3
Study Area Location Codes: Glade Reservoir = GL, Galeton Reservoir = GA, Cactus Hill Reservoir = CH, Glade to Horsetooth Pipeline = GL-HT, U.S. 287 Realignment = U.S. 287,
Carter Pipeline = CP, Cactus Hill to Horsetooth Pipeline = CH-HT, South Platte Water Conservation Project = SPWCP, Poudre Valley Canal = PVC, Agricultural Transfer = AG,
Poudre and South Platte river corridors = CLP/SP.
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6. RESULTS
6.1. Flow-related Indirect Effects Common to All Alternatives (No Action and
Action Alternatives)
Section 6.2.6 of the 2008 Species of Concern Report describes effects on riparian
habitat along the Poudre and South Platte rivers and resulting effects on species of
concern. The analysis of effects on wetland and riparian habitats along the Poudre River
was updated for the SDEIS in the Wetlands and Riparian Resources Effects Technical
Report (ERO 2014) and includes the new No Action Alternative and new Alternative 4.
6.1.1. Effects on Species of Concern from Changes to Wetland and Riparian
Vegetation on the Mainstem
Operation of the NISP alternatives could potentially indirectly affect wetland and
riparian resources along the Mainstem by affecting river flows. The analysis in the
Wetlands and Riparian Resources Effects Technical Report (ERO 2014) found that under
the No Action and action alternatives, plains cottonwoods would likely continue to
decline along the Mainstem because of the current trajectory of decline from past actions,
while nonnative species such as green ash, box elder, Siberian elm, Russian olive, and
reed canarygrass would persist or increase. These habitat changes would occur slowly
and subtly over many years and would occur regardless of whether any of the action
alternatives are implemented. The No Action and action alternatives would result in
decreases to the river stage during the growing season, with similar declines in alluvial
ground water levels and less frequent inundation of cottonwood woodlands. These
changes would contribute to the established trajectory of vegetation changes described
above, but would not affect the overall cover of cottonwoods.
A change from plains cottonwood woodlands that currently dominate the riparian
corridor to the mix of woody riparian species discussed above could potentially affect
species of concern in the riparian corridor. The black-footed ferret, black-tailed prairie
dog, swift fox, burrowing owl, and Bell’s twinpod would not be affected because they do
not occur in riparian habitats. The species of concern potentially occurring in riparian
habitats are discussed below.
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Preble’s Meadow Jumping Mouse
Preble’s occurs in shrub wetlands dominated by sandbar willow. Willow-dominated
communities are less sensitive to river stage declines than herbaceous communities are
because they are more deeply rooted (ERO 2014). Suitable Preble’s habitat is present
along the Mainstem, and occupied habitat is present upstream of Watson Lake (Figure 6).
Ground water declines resulting under the No Action and action alternatives may stress
sandbar willow stands and cause a loss of individuals, but the sandbar willow stands
would recover when supportive hydrology returns in subsequent years. Preble’s habitat
along the banks of the Mainstem is dominated by reed canarygrass and sandbar willow,
two species that can tolerate a range of ground water levels. Changes in streamflow
along the Poudre are not expected to adversely affect woody riparian vegetation, and
effects on Preble’s habitat are not predicted from operation of the alternatives.
Bald Eagle
Bald eagles occurring along the riparian corridor of the Poudre River could be
affected by changes in the vegetation community in the following ways:
Bald eagles are adapted to using the abundant roosts and nesting opportunities,
which plains cottonwoods are well known for producing. The trees predicted to
eventually replace the plains cottonwoods are less likely to provide an abundance
of such habitats.
Establishment of plains cottonwoods frequently are associated with an event that
leads to large stands of even aged trees, which when mature provides potential
roosting structure and large protected nest sites for eagles. This is not true for the
trees predicted to eventually replace the plains cottonwoods. If narrowleaf
cottonwood replaces plains cottonwood in the upper reaches where narrowleaf
cottonwood does not already occur, they would provide similar roosting and nest
sites for bald eagle. Narrowleaf cottonwood is not expected to become dominant
in the lower reaches of the Poudre River because of its ecological preference for
higher elevations.
These changes in the vegetation community would occur regardless of whether the
No Action or action alternatives are implemented, but operation of the No Action and
action alternatives would contribute to the changes.
Colorado Butterfly Plant
No known populations of Colorado butterfly plant occur along the Mainstem.
Potential habitat is unlikely to occur in the Poudre River floodplain as described in the
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2008 Species of Concern Report (ERO 2008). For these reasons, the Colorado butterfly
plant is unlikely to be affected by changes to riparian vegetation and wetlands on the
Mainstem of the Poudre River resulting from operation of the No Action and action
alternatives.
Ute Ladies’-tresses Orchid
No known populations of Ute ladies’-tresses orchid occur along the Mainstem.
Potential habitat is unlikely to occur in the Poudre River floodplain as described in the
2008 Species of Concern Report (ERO 2008). For these reasons, the Ute ladies’-tresses
orchid is unlikely to be affected by changes to riparian vegetation and wetlands on the
Mainstem resulting from operation of the No Action and action alternatives.
Common Gartersnake
Common gartersnakes likely occur in aquatic and riparian habitats along the
Mainstem. Predicted declines in alluvial ground water levels under the No Action and
action alternatives are likely to affect riparian and wetland plant communities that are
shallowly rooted, associated with shallow alluvial ground water levels, and occur close to
the riverbank where changes in river stage have a one-to-one relationship with alluvial
ground water levels (ERO 2014). Declines in alluvial ground water levels within these
potentially sensitive plant communities could result in the following:
Water stress of wetland species with no measurable long-term effect
Shifts in wetland plant species composition toward drier species (e.g., a shift from
obligate to facultative wetland species)
Increases in plant species (native and nonnative) adapted to greater fluctuations in
ground water levels
These changes, in turn, could result in effects on the common gartersnake from
changes to habitat. Common gartersnakes are adapted to a wide range of aquatic,
wetlands, and riparian habitats and would likely adapt to the new habitat conditions. The
effects on the common gartersnake from changes in vegetation would occur over a long
period of time and would likely be imperceptible.
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Northern Leopard Frog
Northern leopard frogs potentially occur within shallow backwaters along the
Mainstem and within associated wetlands. Changes in vegetation along the Mainstem, as
described above for common gartersnake, would also affect northern leopard frog. A
shift from obligate to facultative wetland plant species and increases in plant species
adapted to greater fluctuations in ground water levels could result in a decline in habitat
quality for northern leopard frogs for a portion of their life cycle. The effects would
occur over a long period of time and would likely be imperceptible.
Smokey-eyed Brown Butterfly, Two-spotted Skipper, and American Currant
Potential habitat for the smokey-eyed brown butterfly, two-spotted skipper, and
American currant occurs in riparian areas along the Mainstem. These species occur in
habitat similar to the common gartersnake and northern leopard frog and the effects
would be the same as for those species. The effects would occur over a long period of
time and would likely be imperceptible.
6.2. Effects of No Action Alternative (Alternative 1)
This section replaces Section 6.1 of the 2008 Species of Concern Report (ERO 2008).
As described above, the No Action Alternative described in the 2008 DEIS has been
replaced by a new No Action Alternative for the SDEIS. Effects on species of concern
from development of gravel pits for water storage, as described in the 2008 DEIS, would
not occur. Table 3 summarizes the direct effects on species of concern habitat that would
result from the No Action Alternative and the indirect effect from the irrigated land
dry-up as described below.
Table 3. Direct and Indirect Effects (Acres of Habitat) of the No Action
Alternative (Alternative 1) on Species of Concern.
Habitat Type Permanent1 Temporary2
Preble’s occupied habitat 0 5
Bald eagle nest buffer 9 413
Bald eagle winter concentration area 1 68
Black-tailed prairie dog colony 65 6
Swift fox overall range 2,306 106
Bell’s twinpod locations 0 0
Wetlands (common gartersnake and northern leopard frog
32 16
habitat)4
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Habitat Type Permanent1 Temporary2
Aquatic habitat (common gartersnake and northern leopard
6 17
frog habitat)5
Irrigated land dry-up wetlands (common gartersnake and 218
0
northern leopard frog habitat) (indirect effect)
Riparian woodland habitat (common gartersnake habitat) 4 14
1
Permanent effects include reservoir and dam footprints, forebay, pump stations, associated facilities, pipeline
connections to the reservoir, and realigned roads.
2
Temporary effects include construction effects for dam, reservoirs, pump stations, realigned roads, and other facilities;
access roads; borrow areas; and pipelines.
3
Most of the temporary effects within the bald eagle nest buffer are grasslands, agricultural lands or ditches. About 1.8
acres of Mesic Mixed Woodlands would be affected. It is likely this vegetation type would convert to grasslands,
which would still provide a vegetated buffer for bald eagle nests.
4
Based on wetland effects described in the 2015 Vegetation and Wetland Resources Technical Report Supplement
(ERO 2015).
5
Aquatic habitat includes lakes, ponds, creeks, streams, ditches, and canals as described in the 2015 Vegetation and
Wetland Resources Technical Report Supplement (ERO 2015).
In addition to the direct effects from construction of project components, about
64,200 acres of irrigated agricultural land would be dried up as a result of the No Action
Alternative. Water would be transferred from irrigated land in the Larimer-Weld, New
Cache, and Home Supply irrigation systems to municipal use by the Participants.
Transferred water would include the historical consumptive use portion of these water
rights only. Historical return flow patterns would need to be maintained to prevent injury
to senior water rights. For the Home Supply system, transferred water would continue to
be diverted from the Big Thompson River at its existing diversion location and delivered
to Lonetree Reservoir southwest of Loveland. For the Larimer-Weld and New Cache
systems, water would be diverted from the Poudre River at either the existing diversion
locations or the Poudre Valley Canal diversion at the mouth of the Poudre Canyon.
When diverted at its existing diversion location, Larimer-Weld diversions would flow by
gravity in the existing canal system to Big Windsor.
The methods for estimating losses of wetlands associated with the dry up of
agricultural lands are described in WEST 2010. An estimated 218 acres of irrigated
wetlands would dry up as a result of the No Action Alternative. Dry-up could consist of
either reestablishing native vegetation on the acreages involved or conversion of farming
practices to the production of dry-land crops such as winter wheat. The No Action
Alternative also would result in a large-scale dry-up of irrigation canals, ditches, and
ponds. The irrigated land that would be dried up generally provides low-quality habitat
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because it is supported by flood irrigation and is often subjected to dredging, tilling, and
other disturbances. However, it is possible that losses of irrigated cropland and wetlands,
as well as open water habitat, could affect some species of concern. Agricultural lands
dried up as a result of the No Action Alternative would likely be left untilled for certain
periods and would probably be replaced by areas revegetated to upland grassland habitat,
potentially providing habitat for grassland-associated species of concern.
6.2.1. Federally Listed Threatened, Endangered, and Candidate Species
Preble’s Meadow Jumping Mouse
The No Action Alternative may affect but is not likely to adversely Preble’s because
only about 5 acres of Preble’s habitat would be temporarily disturbed due to construction
of the South Water Treatment Plant to Central Weld County Water District Pipeline. No
Preble’s habitat would be permanently lost. Impacts to Preble’s would be avoided and
minimized through project design and implementation. Additional mitigation actions
such as seasonal restrictions and habitat restoration and creation would be implemented
as part of project design. Irrigated habitats potentially dried up as a result of the No
Action Alternative are subjected to frequent disturbance and are unlikely to support
Preble’s.
Colorado Butterfly Plant
Potential Colorado butterfly plant habitat in the study areas is described in
Section 6.4.1 of the 2008 Species of Concern Report (ERO 2008). No known
populations of Colorado butterfly plant occur in any of the study areas. No populations
were found during surveys conducted prior to the 2008 Species of Concern Report.
Potential habitat could occur where the No Action conveyance pipelines cross the active
floodplain of perennial drainages. Irrigated habitats potentially dried up as a result of the
No Action Alternatives are subjected to frequent disturbance and are unlikely to support
Colorado butterfly plant. At any crossings with suitable habitat, pre-construction surveys
would be conducted to ensure there would be no effect on Colorado butterfly plant.
Ute Ladies’-Tresses Orchid
Potential Ute ladies’-tresses orchid habitat in the study areas is described in
Section 6.4.1 of the 2008 Species of Concern Report. No known populations of Ute
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ladies’-tresses orchid occur in the Cactus Hill Reservoir or Poudre Valley Canal study
areas, or at locations of proposed access roads. No populations were found during
surveys conducted prior to the 2008 Species of Concern Report (ERO 2008). Potential
habitat may occur where the No Action conveyance pipelines cross the active floodplain
of permanent drainages. Habitat assessments or surveys for Ute ladies’-tresses orchid in
areas crossed by the No Action conveyance pipelines would be conducted prior to
construction and effects on new populations would be avoided through construction
design. There would be no effect on Ute ladies’-tresses orchid. Irrigated habitats
potentially dried up as a result of the No Action Alternative are subjected to frequent
disturbance and are unlikely to support Ute ladies’-tresses orchid.
6.2.2. State Species of Concern
Bald Eagle
The No Action Alternative would result in the permanent loss of 9 acres and
temporary disturbance of 41 acres of bald eagle nest buffer (areas within ½ mile of a bald
eagle nest) from construction of Cactus Hill Reservoir and associated facilities. The No
Action Alternative also would result in the permanent loss of 1 acre of bald eagle winter
concentration area from construction of pump stations. The noise and vibration from the
operation of the pump stations would be mitigated by building design. Eagles typically
acclimate to various types of noise. Temporary effects on bald eagle winter
concentration areas would be 68 acres and would result from construction of Cactus Hill
Reservoir, pump stations, and No Action conveyance pipelines. About 65 acres of
black-tailed prairie dog colonies that could potentially provide foraging habitat for bald
eagles also would be permanently lost under this alternative. The permanent and
temporary loss of habitat would be a minor effect on bald eagles because impacts would
be less than 10 percent of eagle habitats (nest buffer and winter concentration area)
available within the Cactus Hill study area and there is other habitat in the area for bald
eagles to use. Construction of Cactus Hill Reservoir would provide habitat for fish,
waterfowl, and other bald eagle prey species. The reservoir would likely become a new
bald eagle winter concentration area and the availability of fish and waterfowl as prey
would offset the losses of prairie dogs as a prey resource resulting in a minor benefit to
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