HomeMy WebLinkAboutLEAP-2023-0004 - DBESP ANALYSIS (2)Determination of
Biologically Equivalent or Superior Preservation (DBESP)
Analysis
For Impacts to MSHCP Riparian/Riverine Areas and Vernal
Pools, and Narrow Endemic/Criteria Area Plants
Baker Industrial Project
Permittee
City of Lake Elsinore
Applicant
Ecosystem Investment Partners
1505 Bridgeway, Suite 107
Sausalito, California 94965
Contact: Glen Williams
Phone: (415) 465-4423
Consultant
Glenn Lukos Associates, Inc.
1940 E. Deere Avenue, Suite 250
Santa Ana, California 92705
Contact: David Moskovitz
Phone: (949) 340-2562
February 28, 2024
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Contents
1.0 EXECUTIVE SUMMARY ......................................................................................... 3
2.0 INTRODUCTION ...................................................................................................... 3
2.1 Project Area ....................................................................................................... 3
2.2 Project Description ............................................................................................. 4
2.3 Existing Conditions ............................................................................................. 8
3.0 RIPARIAN/RIVERINE MITIGATION (SECTION 6.1.2) .......................................... 10
3.1 Methods ........................................................................................................... 10
3.2 Results/Impacts ................................................................................................ 14
3.3 Mitigation and Equivalency............................................................................... 21
4.0 NARROW ENDEMIC PLANT SPECIES MITIGATION (SECTION 6.1.3) .............. 25
4.1 Methods ........................................................................................................... 25
4.2 Results/Impacts ................................................................................................ 26
4.3 Mitigation and Equivalency............................................................................... 26
5.0 ADDITIONAL SURVEY NEEDS (SECTION 6.3.2) ................................................ 27
5.1 Criteria Area Species Survey Area - Plants ..................................................... 27
5.2 Burrowing Owl .................................................................................................. 29
5.3 Mammals.......................................................................................................... 31
5.4 Amphibians ...................................................................................................... 31
6.0 DELHI SANDS FLOWER-LOVING FLY ................................................................. 32
7.0 REFERENCES....................................................................................................... 32
TABLES
Table 2-1. Summary of Project Components ................................................................. 5
Table 2-2. Summary of Vegetation/Land Use Types for the Project Site ....................... 9
Table 3-1. Summary of Least Bell’s Vireo Surveys ...................................................... 13
Table 3-2. Summary of Southwestern Willow Flycatcher Surveys ............................... 14
Table 3-3. MSHCP Riparian/Riverine Areas at the Project site .................................... 14
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Table 3-4. Impacts to MSHCP Riverine Areas ............................................................. 17
Table 3-5. MSHCP Vernal Pools at the Project Site ..................................................... 18
Table 3-5. Summary of Peak Flows Existing Versus Proposed (in cfs) ........................ 23
Table 3-6. Summary of Peak Flows Existing Versus Proposed (in cfs) ........................ 24
Table 5-1. Summary of Burrowing Owl Surveys ........................................................... 30
EXHIBITS
Exhibit 1 Regional Map
Exhibit 2 Vicinity Map
Exhibit 3 Project Components Map
Exhibit 4A MSHCP Overlay Map
Exhibit 4B MSHCP Species Survey Area Map
Exhibit 5 Vegetation Map
Exhibit 6 Soils Map
Exhibit 7 MSHCP Riparian/Riverine Areas and Vernal Pools
Exhibit 8 Rare Plants Map
Exhibit 9 Plant Restoration Map
Exhibit 10 Burrowing Owl Survey Map
Exhibit 11 Site Photographs
APPENDICES
Appendix A Conceptual Grading Plan – Baker Industrial Project
Appendix B Biological Technical Report
Appendix C Report of 2021 Dry Season Fairy Shrimp Surveys
Appendix D Report of 2023 Dry Season Fairy Shrimp Surveys [Pending]
Appendix E Report of 2023/2024 Wet Season Fairy Shrimp Surveys [Pending]
Appendix F Report of 2020 Southwestern Willow Flycatcher and Least Bell’s
Vireo Surveys
Appendix G Preliminary Drainage Report
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1.0 EXECUTIVE SUMMARY
This document provides an analysis in support of a Determination of Biologically
Equivalent or Superior Preservation (DBESP) for the Baker Industrial Project (the
Project) located in the City of Lake Elsinore, Riverside County, California, in regard to
the Multiple Species Habitat Conservation Plan (MSHCP) requirements for Protection of
Species Associated with Riparian/Riverine Areas and Vernal Pools (MSHCP Volume I,
Section 6.1.2).
This document has been prepared following the MSHCP DBESP Report Template
created by the Regional Conservation Authority (RCA), to demonstrate that with the
appropriate mitigation, the Project will represent a “biologically equivalent or superior”
alternative to avoidance. This document summarizes the findings of general biological
surveys, habitat assessments, and vegetation mapping, as they relate to riparian and
vernal pool resources, and species with MSHCP survey requirements.
2.0 INTRODUCTION
2.1 Project Area
The Project site comprises approximately 124.60 acres in the City of Lake Elsinore,
Riverside California [Exhibit 1 – Regional Map] and is located within an un-sectioned
portion of Township 5 South, Range 5 West, of the U.S. Geological Survey (USGS) 7.5-
minute quadrangle map Lake Elsinore, California [Exhibit 2 – Vicinity Map]. The Project
site is located southwest of Interstate-15, the Lake Elsinore Outlet Center and Temescal
Creek/Collier Marsh. The Project site includes the following Assessor’s Parcel Numbers
(APNs):
Onsite
378-020-014
378-020-015
378-020-016
378-020-028
378-020-029
378-020-030
378-020-031
378-020-036
378-020-037
378-020-048
Offsite
378-020-012
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378-020-038
378-020-039
378-020-042
378-020-043
378-114-064
389-080-058
389-080-013
RCA Conserved Land
378-020-024
378-020-033
378-020-034
378-020-040
378-020-041
378-020-054
2.2 Project Description
2.2.1 General Description
The overall Project site totals 124.60 acres and is presented here in five distinct
components:
1. The Industrial Project development footprint (referred to as the “onsite” portion of
the Project)
2. Baker Street Improvements (offsite)
3. A proposed City Maintenance Area (offsite) – to be located along the edge of
Baker Street
4. Additional Street Improvements (offsite) – includes improvements to Pierce
Street and Nichols Road
5. RCA Conserved Lands – includes 33.66 acres of lands to be conserved by the
Project located northeast of the proposed City Maintenance Area and southeast
of Pierce Street/Nichols Road
The five Project components are depicted on Exhibit 3 [Project Components Map].
Table 2-1 summarizes the acreages of these five components, broken out for portions
inside versus outside of Criteria Cells.
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Table 2-1. Summary of Project Components
Project Component Inside
Criteria Cells
(Acres)
Outside
Criteria Cells
(Acres)
Total
(Acres)
Industrial Project 34.25 31.56 65.81
Baker Street Improvements 4.45 1.66 6.11
City Maintenance Area 2.44 0.29 2.73
Additional Street
Improvements
5.83 10.46 16.29
RCA Conserved Lands 32.00 1.66 33.66
Total 78.97 45.63 124.60
2.2.2 Industrial Project (Onsite)
The Baker Industrial Project (Project) is proposing two industrial buildings for a total of
approximately 1,002,000 square feet of industrial space. The proposed site plan
provides adequate standard vehicle parking fields and an additional trailer parking field
along the southern end of the property.
The Project grading consists of a development pad graded to convey onsite and offsite
stormwater northerly while maintaining the hydrologic regime of the property and
surrounding tributaries. Larger slopes and associated retaining walls are located along
the southerly property line.
The Project will accept offsite flows from the southern tributaries (developed) through
two flow-by basins also located along the southerly property line. Storm flows are then
conveyed through the Project storm system and discharged in flow and quantity at their
historical locations along the northern side of Baker Street. Onsite flows are collected
through inlets/catch basins and conveyed through the proposed storm drain system to
one of three underground storm chambers. With limited opportunities to infiltrate onsite
storm flows, each chamber system will treat the pollutants of concern and discharge all
treated flows consistent with historical quantities and flow characteristics along the
northerly right-of-way of Baker Street.
The Project includes the preparation of a Preliminary Hydrology Study to analyze the
existing condition storm flows across the property as well as the proposed condition
conveyances to existing discharge locations. The hydrology study will confirm flow
values based on standard storm intensities and discharge volumes, flow rates, and
velocities. The Project also includes a Preliminary Water Quality Management Plan
(WQMP) that identifies the Best Management Practices (BMPs) proposed to be
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implemented to treat project related pollutants for onsite and offsite impervious
improvements. The WQMP will identify the post-construction treatment control and site
design BMPs to treat specific pollutants from onsite impervious areas as well as the
public right-of-way prior to discharge at historical locations on the northern side of the
proposed Baker Street corridor improvements. BMPs located within the public right-of-
way of Baker Street and Nichols Road will treat roadway specific pollutants within bio-
retention/modular wetland facilities upstream of the specified discharge locations. A
Storm Water Pollution Prevention Plan (SWPPP) will be prepared and implemented
prior to onsite and offsite project construction disturbance. The SWPPP will focus on the
design, installation, and treatment of construction related pollutants. The SWPPP
document will be approved through the State of California and the Project will be
registered as required by the Construction General Permit. The Project will be
monitored before, during and after rain events to ensure BMP implementation and
effectiveness in protecting downstream habitats and receiving water bodies.
The Project proposes to construct an 8-inch sewer pipeline within Baker Street to
convey wastewater flows north westerly to the existing Nichols Road Lift Station. The
pipeline is proposed at standard depth and will connect to the existing Elsinore Valley
Municipal Water District (EVMWD) 15-inch sewer line constructed within the Pierce and
Baker intersection. The Nichols Lift Station will require an upgrade to its ultimate build-
out capacity. The lift station upgrades will occur within the existing EVMWD parcel and
will also require an upsized force main between the lift station and the discharge
manhole within the Nichols and Collier intersection. EVMWD has master planned a new
force main from the permanent lift station to convey flow south in Baker Street to
Turnbull Avenue. From there a new gravity sewer line is identified in Turnbull Avenue
and south to the Regional Wastewater Treatment Plant. The gravity sewer alignment
would require construction of many sections of the gravity sewer line in private streets
and private property where easements would need to be acquired. The EVMWD
Master Plan exhibit in Attachment 2 provides the proposed alignment of the force main
and downstream gravity sewer.
An alternative sewer force main alignment was studied by KWC Engineers in 2015 that
would route the force main in Collier Avenue. The force main and downstream gravity
sewer improvements under the revised alignment would keep all improvements within
existing public right-of-way. The Collier Avenue alignment would also allow the
improvements to be phased by constructing a force main with the first phase of the
permanent lift station and then constructing a parallel or replacement force main when
the lift station is expanded to its ultimate capacity. The Collier Avenue alignment
alternative was reviewed with EVMWD staff recently and they take no objection to
proceeding with that alignment. EVMWD did, however, note that they will need to
evaluate the downstream impacts of flows routed down Collier Avenue and that
depending on the extent of required downstream improvements, not all the
improvements may be eligible for fee credits. Once the capacity study currently being
reviewed by EVMWD is approved, KWC will initiate the PDR for the lift station and
coordinate with EVMWD on the downstream sewer system analysis.
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For water service, an EVMWD 36-inch 1434 Zone CIP line is proposed to be installed in
Nichols Road from Terra Cotta Road to Baker Street and in Baker Street to the existing
20-inch line that supplies the Baker Reservoir. The Project proposes to receive water
service by making two connections to the proposed transmission line in Baker Street
and constructing a looped piping system onsite between the two connections. EVMWD
does not allow fire hydrants to be served off private systems so the onsite loop will need
to be public. The onsite line will be located in an easement and be located in
accordance with EVMWD requirements which includes not locating the line beneath
landscaped medians or parking stalls. The 1434 Zone has a large surplus of reservoir
storage capacity and additional storage is not required to provide service to the Project.
The 1434 Zone has a large surplus of reservoir storage capacity and additional storage
is not required to provide service to the Project.
2.2.3 Baker Street (Offsite)
Existing Baker Street is an unimproved dirt road with a 60-foot-wide right-of-way. The
Project proposes to dedicate four feet on each side of Baker Street to the ultimate 68
feet right-of-way required by the City of Lake Elsinore’s (City) Collector roadway
designation and as listed within the City’s circulation element. The Project will also be
realigning Baker Street for a direct connection and new intersection with Nichols Road,
which is discussed below under “Additional Street Improvements”. The Baker Street
Collector section consists of a six-inch curb and gutter, a five-foot-wide sidewalk within
a 10-foot parkway and 22 feet of pavement from centerline to lip of gutter on each side
of the street. Baker Street is proposed to be elevated an average of five feet above its
existing elevations to support drainage conveyance and flood protection of the public
right-of-way. The northeast parkway of Baker Street will slope down from the proposed
five-foot sidewalk to daylight within the northerly properties.
The Project proposes to elevate the road surface of Baker Street to support drainage
protection and conveyance. Along the northern edge of Baker Street, a graded and
landscaped slope will daylight to existing ground within the parcels north of existing
Baker Street right-of-way. The proposed slope will provide areas to safely construct
storm drain outlets that will convey historical storm flows to existing flow lines and
environmentally sensitive areas identified within the Project studies of these properties.
The storm outlets will include energy dissipation improvements to control the storm
water outlet depth and velocity to mimic existing conditions.
2.2.4 City Maintenance Area (Offsite)
As noted above, the Project proposes to elevate the road surface of Baker Street to
support drainage protection and conveyance. Along the northern edge of Baker Street,
a graded and landscaped slope will daylight to existing ground within the parcels north
of existing Baker Street right-of-way. The proposed slope will provide areas to safely
construct storm drain outlets that will convey historical storm flows to existing flow lines
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and environmentally sensitive areas identified within the Project studies of these
properties. The storm outlets will include energy dissipation improvements to control the
storm water outlet depth and velocity to mimic existing conditions.
A maintenance access road is proposed along the toe-of-slope for ongoing
maintenance of the slope, the associated landscaping, any required fencing, and the
outlet structures. Where sensitive environmental areas exist (vernal pools identified
within the Project environmental studies), the improvements are proposed to be scaled
back to minimize or eliminate impacts in and adjacent to the defined zones.
Construction buffers will be implemented to reduce accidental disturbance and the
areas will be clearly delineated and recognizable to construction crews/personnel.
2.2.5 Additional Street Improvements (Offsite)
In addition to the Baker Street improvements described above, the Project will also
improve Pierce Street and Nichols Road. The Project will realign Baker Street for a
direct connection and new intersection with Nichols Road. The intersection design will
likely consist of signal pole placement consistent with the ultimate build-out of Nichols
Road (Urban Arterial Highway – 120’ right-of-way). Nichols Road improvements will
likely consist of an interim intersect with appropriate pavement tapering to the east and
west leading away from the new intersection with Baker Street. Minor roadway
resurfacing may be required along the existing Nichols Road segment between the
Baker Street intersection and the Collier Avenue intersection. The Nichols and Collier
intersection may also include minor surface improvements, revised lane striping and
potential traffic control/signage improvements.
Existing Pierce Street varies in right-of-way width along the Project’s frontage. The
Project proposes to construct Pierce Street to its ultimate 60-foot width between Baker
Street and Hoff Avenue. The ultimate street section will include a six-inch curb, standard
gutter, five-foot-wide sidewalk within an overall 10-foot parkway and 18 feet of
pavement from centerline to lip-of-gutter on each side of the street. Other project related
street improvements beyond the Project frontage will be assessed with the traffic impact
analysis.
2.2.6 RCA Conserved Land
The Project is conserving 33.66 acres of lands bordered by the Baker Street, Pierce
Street and Nichols Road improvements.
2.3 Existing Conditions
The overall Project site varies in topography from slightly hilly to flat, sloping from
southwest to northeast. The onsite portion of the Project site (industrial component)
consist of several small hills and ridges sloping from the southwest down to the existing
dirt road of Baker Street, with the site being flatter on the northern end near the Baker
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Street/Pierce Street intersection. Northeast of Baker Street, the landscape is flat with a
very gradual change in elevation to the northeast towards Alberhill Creek/Collier Marsh.
Elevations at the Project site range from approximately 1,400 feet above mean sea level
(AMSL) at the southwestern boundary of the development footprint to 1,250 feet AMSL
at the northeastern limits of the proposed RCA Conserved Lands.
Soils within the onsite portion of the Project site consist mainly Lodo Rocky Loam and
Willows Silty Clay (saline-alkali). The Willows soils occur in the lower portions of site,
with the rocky loam soil occurring in the higher elevation areas. The Willows soils
extend into the site from the adjacent Collier Marsh area. These alkaline soils are
strongly associated with the plant species that occur occurring in the vernal pools
immediately northeast of Baker Street. The offsite (undeveloped) portions of the Project
site predominantly consist of fine sandy loam soils. The proposed RCA Conserved
Lands consist of Willows silty clay soils as well as the fine sandy loam soils.
GLA mapped nine distinct vegetation/land use types for the Project site, including Akali
Grassland, Akali Playa, Disturbed/Developed, Open Water, Riversidean Sage Scrub,
Semi-Natural Herbaceous Grassland, Disturbed Semi-Natural Herbaceous Grassland,
Southern Willow Scrub and Vernal Pool. Table 2-2 provides a summary of the
vegetation types and their corresponding acreage. A Vegetation Map is attached as
Exhibit 6. Photographs depicting the Project site are shown in Exhibit 12.
Table 2-2. Summary of Vegetation/Land Use Types for the Project Site
Vegetation/Land Use Type
Inside
Criteria Cells
(acres)
Outside
Criteria Cells
(acres)
Total
(acres)
Alkali Grassland 4.06 0 4.06
Alkali Playa 0.73 0 0.73
Disturbed/Developed 9.62 8.72 18.34
Open Water 0.09 0 0.09
Riversidean Sage Scrub 2.49 0.52 3.01
Semi-Natural Herbaceous Grassland 38.88 30.83 69.71
Disturbed Semi-Natural Herbaceous
Grassland 20.71 5.56 26.27
Southern Willow Riparian Scrub 1.14 0 1.14
Vernal Pool 1.25 0 1.25
Total 78.97 45.63 124.60
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3.0 RIPARIAN/RIVERINE MITIGATION (SECTION 6.1.2)
3.1 Methods
3.1.1 Riparian/Riverine Areas
The MSHCP defines riparian areas as “lands which contain habitat dominated by trees,
shrubs, persistent emergent mosses and lichens, which occur close to, or which depend
upon soils moisture from a nearby fresh water source. In the absence of riparian habitat,
the MSHCP defines riverine areas as areas with fresh water flow during all or a portion
of the year.”
GLA surveyed the Project site for riparian/riverine areas. GLA biologists Jillian
Stephens and David Moskovitz initially evaluated the site in April 2020, with follow-up
visits conducted by GLA regulatory specialists Chris Waterston and Lesley Lokovic-
Gamber on February 9, 2021, and April 20 and July 29, 2022.
3.1.2 Vernal Pools
The MSHCP defines vernal pools as “seasonal wetlands that occur in depression areas
that have wetlands indicators of all three parameters (soils, vegetation, and hydrology)
during the wetter portion of the growing season but normally lack wetland indictors of
hydrology and/or vegetation during the drier portion of the growing season.”
GLA surveyed the Project site for vernal pools as part of the jurisdictional delineation to
identify seasonal wetlands. GLA biologists evaluated the topography of the site,
including whether the site contained depressional features/topography with the potential
to become inundated; whether the site contained soils associated with vernal/seasonal
pools; and whether the site supported plants that suggested areas of localized ponding.
The site was evaluated on multiple occasions during the rainfall season, including in
2020, 2021 and 2022. GLA biologists Jillian Stephens and David Moskovitz initially
evaluated the site in April 2020, with follow-up visits conducted on February 9, 2021,
and April 20, 2022.
3.1.3 Fairy Shrimp
The Project site contains four seasonally ponding features with a potential to support
listed fairy shrimp, including one stock pond feature within the Industrial portion of the
Project, and three vernal pools that either overlap with the offsite improvements and
maintenance area associated with Baker Street or are immediately adjacent in the
proposed RCA Conserved Lands. All four features require protocol surveys (dry season
and wet season) to determine the presence or absence of listed fairy shrimp. GLA
initially documented the four features in April 2020 and intended to perform wet and dry
season surveys in 2021; however, the wet season survey could not be performed in
2021 due to insufficient rainfall. Dry season surveys were then intended to be
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performed in 2021. The lands containing two of the pools were disked and so soil
samples were not collected from those pools; however, soil samples were collected
from the two pools that were not disked and cysts of the Genus Branchinecta were
detected in both pools [Appendix C – 2021 Dry Season Fairy Shrimp Report]. To
complete the survey protocol for all four features, dry season surveys are in progress
with wet season surveys to be conducted for the upcoming 2023-2024 rainfall season.
Dry Season Surveys
Soil sample collection followed the USFWS Survey Guidelines for the Listed Large
Branchiopods (Survey Guidelines). 1 GLA biologist David Moskovitz (PER0010680-0)
supervised the collection of soil samples along with GLA biologists Stephanie Cashin
and Chris Waterston in October and November 2023. Soil samples were collected
when the pools were dry using a hand trowel to collect intact chunks of soil from the top
1–3 cm of pool sediment. The number of soil samples collected from each of features
was based on feature size according to the Survey Guidelines. Starting at the edge of
each depression, samples were taken from equidistant points along the longest transect
and widest transect of each depression. Additional samples were taken at the deepest
part of each feature.
Soil samples of approximately 100 milliliters (ml) each were removed at each sub-
sample location using a hand trowel and were combined into a labeled bag for each
feature with the collection date, location and feature ID, and name of collector for future
processing. Samples were stored in a dry location out of direct sunlight until delivery to
Helm Biological Consulting (HBC) for processing. The results of the soil processing are
pending and will be detailed in a separate Dry Season Survey Fairy Shrimp Report,
which will be Appendix D for a future version of this Consistency Analysis.
Wet Season Surveys
Wet season fairy shrimp surveys will be performed for the four seasonal pond features
for the 2023-2024 rainfall season, as a follow up to the pending dry season surveys. In
accordance with the USFWS Survey Guidelines for the Listed Large Branchiopods
(Survey Guidelines) dated November 13, 2017, site visits will be conducted following
measurable rainfall events to determine whether any of the features contained a
minimum of three centimeters (cm) of ponding after 24 hours from the rainfall event.
Under typical conditions, sampling will commence within seven days of initial ponding.
Sampling will continue weekly until the features are dry or have been inundated
continuously for 120 days. If dried features re-inundate, sampling will begin again as
above. Sampling for the presence of fairy shrimp will be performed using a dip net
within representative portions of the depression bottom, edges, and vertical water
column when there is adequate ponding. Specimens will be placed into vials, with
1 USFWS. Survey Guidelines for the Listed Large Branchiopods, Revised: November 13, 2017.
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unique depression information, containing 95% ethanol solution. Specimens will be
identified through microscopy and using the “Key to California Fairy Shrimps” found in
Eriksen and Belk (1999, Revised 2016).2 The results of the wet season surveys will be
detailed in a separate Wet Season Survey Fairy Shrimp Report, which will be Appendix
E for a future version of this Consistency Analysis.
3.1.4 Riparian Birds
The MSHCP requires habitat assessments and focused surveys (if suitable habitat) for
least Bell’s vireo (Vireo bellii pusillus), southwestern willow flycatcher (Empidonax traillii
extimus), and western yellow-billed cuckoo (Coccyzus americanus occidentalis). The
proposed development areas of the Project do not contain suitable habitat for these
species; however, Alberhill Creek contains suitable habitat for the vireo and flycatcher,
and because the proposed improvements to Nichols Road are adjacent to the creek,
focused surveys were conducted for both species. GLA performed protocol surveys for
least Bell’s vireo and southwestern willow flycatcher in 2020. The survey methods and
results are summarized here. A separate survey report is included as Appendix F.
Least Bell’s Vireo
GLA biologists Stephanie Cashin, Jeff Ahrens and April Nakagawa conducted focused
surveys for the least Bell’s vireo within the portions of Alberhill Creek in proximity to the
Project site. Surveys were conducted in accordance with the 2001 USFWS survey
guidelines, which stipulate that eight surveys should be conducted between April 10 and
July 31, with a minimum of ten days separating each survey visit.
Focused surveys were conducted on April 13, May 5, 18 and 28, June 8 and 19, and
July 15 and 28, 2020. Pursuant to the survey guidelines, the surveys were conducted
between sunrise and 11:00 a.m. Weather conditions during the surveys were
conducive to a high level of bird activity. Table 3-1 summarizes the vireo survey visits.
2 Eriksen, C. and D. Belk. 1999. Fairy Shrimps of California’s Puddles, Pools, and Playas. Mad River Press, Inc.
Eureka, California.
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Table 3-1. Summary of Least Bell’s Vireo Surveys
Survey Date Biologist(s) Start/End
Time
Start/End
Temperature
(°F)
Start/End
Wind
Speed
(mph)
Cloud
Cover
4/13/20 SC 0620/1000 60/68 0-1/0-1 100/100
5/5/20 JA 0550/0920 56/75 1-2/0-2 0/0
5/18/20 JA 0550/1100 57/69 1-2/1-2 80/50
5/28/20 AN 0600/1100 62/84 0-1/0-1 0/0
6/8/20 AN 0645/1100 58/75 8-10/8-10 0/0
6/19/20 SC 0615/1015 59/67 0-2/0-1 100/50
7/15/20 AN 0645/1100 62/77 0-1/0-1 100/0
7/28/20 AN 0700/1100 62/88 0-1/4-5 0/0
SC = Stephanie Cashin; JA = Jeff Ahrens; AN = April Nakagawa
Southwestern Willow Flycatcher
GLA biologist Jeff Ahrens conducted focused surveys for the southwestern willow
flycatcher for all suitable habitat areas within the Project site. Surveys were conducted
in accordance with the 2010 USFWS survey guidelines, which stipulate five survey
visits between May 15 and July 17, divided into three survey periods. The southwestern
willow flycatcher is one of three subspecies of willow flycatcher that occur within
southern California but is the only subspecies that breeds in southern California. The
other subspecies may occur in southern California as they migrate through the area
onwards to northern breeding areas but will not breed in southern California. If present,
these subspecies may be detected during the first and/or second survey periods. The
presence of the southwestern willow flycatcher is determined by willow flycatchers that
remain in southern California during the third survey period.
Focused surveys were conducted on May 18, June 9 and 23, and July 1 and 16, 2020.
Pursuant to the survey guidelines, the surveys were conducted between one hour prior
to sunrise and 10:00 a.m. Weather conditions during the surveys were conducive to a
high level of bird activity. Table 3-2 summarizes the flycatcher survey visits.
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Table 3-2. Summary of Southwestern Willow Flycatcher Surveys
Survey Date Biologist(s) Start/End
Time
Start/End
Temperature
(°F)
Start/End
Wind
Speed
(mph)
Cloud Cover
5/18/20 JA 0550/1100 57/69 1-2/1-2 80/50
6/9/20 JA 0600/0940 53/73 1-2/1-2 0/0
6/23/20 JA 0555/1000 58/68 0-1/0-1 100/0
7/1/20 JA 0555/0930 60/66 1-2/1-2 100/100
7/16/20 JA 0550/0930 59/72 1-2/0-1 30/0
JA = Jeff Ahrens
3.2 Results/Impacts
3.2.1 Riparian/Riverine Areas
The Project site contains approximately 3.03 acres of MSHCP riparian/riverine areas,
including 2.36 acres of riparian habitats associated with Alberhill Creek, and 0.67 acre
associated with six drainage features (Drainage A through F) [Exhibit 8 – MSHCP
Riparian/Riverine Areas and Vernal Pools]. Approximately 2.58 acres of
riparian/riverine areas are inside Criteria Cells and 0.45 acre of riverine areas are
outside Criteria Cells. The 2.36 acres associated with Alberhill Creek includes 1.14
acres of Southern Willow Riparian Scrub, 0.73 acre of Alkali Playa, 0.09 acre of Open
Water, and 0.40 acre of Semi-Natural Herbaceous Grassland. Table 3-3 below
summarizes the riparian/riverine areas at the Project site.
Table 3-3. MSHCP Riparian/Riverine Areas at the Project site
Inside Criteria Cells Outside Criteria Cells
Drainage Riverine
(acres)
Riparian
(acres)
Riverine
(acres)
Riparian
(acres)
Total
(acres)
Alberhill Creek 0 2.36 0 0 2.36
Drainage A 0.15 0 0.03 0 0.18
Drainage B 0 0 0.13 0 0.13
Drainage C 0.03 0 0 0 0.03
Drainage D 0 0 0.09 0 0.09
Drainage E 0.04 0 0 0 0.04
Drainage F 0 0 0.20 0 0.20
Total 0.22 2.36 0.45 0 3.03
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Alberhill Creek
Alberhill Creek enters the Project’s RCA Conserved Land from the southeast and
extends in a northwesterly direction before exiting the conserved parcels just before the
Nichols Road crossing.
Alberhill Creek is dominated by southern willow scrub riparian habitat with an alkali
playa component occurring in the abutting floodplain. A majority of the alkali playa
component in the northeastern portion of the site exhibits at least some degree of soil
disturbance and alterations to the hydrologic regime as evidenced by the presence of
tire tracks, road ruts, and unauthorized dumping.
Dominant riparian/wetland vegetation associated with Alberhill Creek includes salt cedar
(Tamarix ramosissima), black willow (Salix gooddingii), arroyo willow (Salix lasiolepis),
and mulefat (Baccharis salicifolia), with alkali bulrush (Bolboschoenus maritimus),
common toad rush (Juncus bufonius), and cattail (Typha spp.). Other common plants
include common nettle (Urtica dioica), shortpod mustard (Hirschfeldia incana),
silverscale saltbush (Atriplex argentea), San Jacinto Valley crownscale (Atriplex
coronata var. notatior), western ragweed (Ambrosia psilostachya), saltgrass (Distichlis
spicata), and annual rabbitsfoot grass (Polypogon monspeliensis).
Drainage A
Drainage A originates offsite to the southwest, extending through the onsite portion of
the Project to Baker Street where it crosses under Baker Street through a pipe culvert
continuing in a northeasterly direction before its confluence with Alberhill Creek. The
lower portion of Drainage A in the parcel boundary drains into one of three seasonal
ponds (described separately below) before continuing its course towards Alberhill
Creek. Drainage A ranges from two to six feet in width as evidenced by water marks,
changes in soil characteristics, and bent vegetation.
Vegetation associated with Drainage A includes foxtail barley (Hordeum murinum), soft
chess (Bromus hordeaceus), ripgut brome (Bromus diandrus), red brome (Bromus
madritensis ssp. rubens), rattail fescue (Festuca myuros), common Mediterranean
grass (Schismus barbatus), cheeseweed (Marva parviflora), wild oats (Avena fatua),
common fiddleneck (Amsinckia intermedia), stinknet (Oncosiphon piluliferum), annual
mustard (Brassica ssp.), shortpod mustard, goldenbush (Isocoma menziesii), London
rocket (Sisybrium irio), alkali heliotrope (Heliotropium curassavicum), and a single
tamarisk. Additional species observed in the downstream reach include salt grass,
alkali weed, ragweed, and a single tamarisk. This feature flows only in direct response
to precipitation and was completely dry during the field investigations.
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Drainage B
Drainage B is an earthen ephemeral drainage that enters the Baker parcel from the
west along the edge of a former residential property and extends in a northeasterly
direction towards Baker Street. Drainage B conveys storm water flows and receives
irrigation runoff from the adjacent rural residence. The drainage extends up to ten feet in
width as evidenced by changes in soil characteristics and bent vegetation.
Vegetation associated with Drainage B consists primarily of semi-natural herbaceous
grassland that includes foxtail barley, soft chess, ripgut brome, red brome, rattail fescue,
common Mediterranean grass, cheeseweed, wild oats, common fiddleneck, stinknet,
annual mustard, summer mustard, goldenbush, heliotrope, and London rocket.
Drainage C
Drainage C is an erosional ephemeral drainage that originates offsite from the adjacent
hillsides and extends in a northerly direction towards Baker Street. Drainage C
averages two feet in width as evidenced by changes in soil characteristics and eroded
channel banks in the upstream reach. The drainage bottom contains cobbles and was
completely dry during the field investigations.
Vegetation associated with Drainage C consists primarily of semi-natural herbaceous
grassland that includes foxtail barley, soft chess, ripgut brome, red brome, rattail fescue,
common Mediterranean grass, cheeseweed, wild oats, common fiddleneck, stinknet,
annual mustard, summer mustard, goldenbush, heliotrope, and London rocket. Areas
adjacent to the drainage contain patches of California buckwheat (Eriogonum
fasciculatum), bush sunflower (Encelia californica), and California sagebrush (Artemisia
californica).
Drainage D
Drainage D is an erosional drainage that occurs in the southwestern portion of the
Baker parcel. The drainage originates offsite from the southwest and meanders in a
northeasterly direction before exiting the parcel boundary at an existing rural residence.
Drainage D ranges between two and six feet in width and contains eroded banks and
cobbles. This feature conveys flow only in direct response to precipitation and was
completely dry during the field investigation.
Vegetation associated with Drainage D consists primarily of semi-natural herbaceous
grassland that includes foxtail barley, soft chess, ripgut brome, red brome, rattail fescue,
common Mediterranean grass, cheeseweed, wild oats, common fiddleneck, stinknet,
annual mustard, summer mustard, goldenbush, heliotrope, and London rocket. Areas
adjacent to the drainage contain patches of California buckwheat, bush sunflower, and
California sagebrush.
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Drainage E
Drainage E is an earthen ephemeral drainage that originates as run-off from Nichols
Road. This feature extends in an easterly direction before dissipating as sheet flow. The
drainage averages three feet in width, and depending on rainfall amounts, conveys a
surficial connection to Alberhill Creek. Vegetation associated with the drainage is limited
to non-native upland grasses and weeds including foxtail barley, soft chess, ripgut
brome, red brome, rattail fescue, common Mediterranean grass, cheeseweed, wild oats,
common fiddleneck, stinknet, annual mustard, summer mustard, heliotrope, and London
rocket. This drainage lacks hydrophytic vegetation and was completely dry during the
field investigations.
Vegetation associated with Drainage E consists primarily of semi-natural herbaceous
grassland that includes foxtail barley, soft chess, ripgut brome, red brome, rattail fescue,
common Mediterranean grass, cheeseweed, wild oats, common fiddleneck, stinknet,
annual mustard, summer mustard, goldenbush, heliotrope, and London rocket.
Drainage F
Drainage F consists of a roadside drainage channel along the northern edge of Nichols
Road. This feature extends in an easterly direction. The drainage averages six feet in
width and is generally unvegetated.
The proposed Project will permanently (directly) impact approximately 0.50 acre of
MSHCP riverine areas but will not impact any riparian habitat. Impacts will occur to five
drainage features (A, B, C, D and F). Table 3-4 summarizes impacts to riverine
features.
Table 3-4. Impacts to MSHCP Riverine Areas
Drainage Inside
Criteria Cells
(acres)
Outside
Criteria Cells
(acres)
Total Impacts
(acres)
Drainage A 0.02 0.03 0.05
Drainage B 0 0.13 0.13
Drainage C 0.03 0 0.03
Drainage D 0 0.09 0.09
Drainage F 0 0.20 0.20
Total 0.05 0.45 0.50
The drainage features to be impacted by the Project are vegetated with semi-natural
herbaceous grassland, which is dominated by a mix of non-native grasses and native
and non-native forbs. As such, the drainages to not support biological functions for the
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MSHCP Section 6.1.2 species. The functions of the drainage features are limited to
hydrologic functions, specifically conveyance downstream towards the Alberhill Creek
floodplain. The drainage features collect runoff from the southwest and generally
convey flows to the northeast. As documented in the Project’s Preliminary Drainage
Report (Appendix G), the Project is designed to collect the runoff and mimic the existing
hydrologic conditions of the drainages to the maximum extent feasible, such that the
Project is not expected to adversely affect the hydrologic functions of the drainages.
3.2.2 Vernal Pools
The Project site contains three areas on the northeastern side of Baker Street that pond
seasonally and exhibit the three wetland parameters to meet the definition of MSHCP
Vernal Pools. These areas are referenced herein as Vernal Pools 1, 2, and 3, all of
which are inside Criteria Cells. Vernal Pools 1 and 2 are in proximity to, but do not
directly abut, Alberhill Creek. Vernal Pool 3 is connected to Drainage A, which connects
with Alberhill Creek. All three vernal pools are in areas mapped as containing Willows
Silty Clay soils [Exhibit 7 – Soils Map]. Each of the vernal pools, as described below,
are unique in terms of their hydrology, soils appearance, relationship to the ecosystem
and vegetation assemblage. Table 3-5 summarizes vernal pools at the Project site and
impacts to those pools.
Table 3-5. MSHCP Vernal Pools at the Project Site
Vernal Pool Total Pool
Area
(acres)
Impacts to
Vernal Pools
(acres)
Vernal Pool 1 0.21 0
Vernal Pool 2 0.40 0.01
Vernal Pool 3 0.63 0.07
Total 1.24 0.08
Vernal Pool 1
Vernal Pool 1 is approximately 0.21 acre. The vernal pool is in an area mapped as
containing Willow Silty Clay soils (saline-alkali) and the strong alkaline component is
evident in the white color of the spoils. The main ponding area does not become
heavily vegetated due to the alkalinity; however, the areas surrounding the ponding
basin supports species such as salt grass, Coulter’s goldfields, vernal barley, and San
Jacinto Valley crownscale. Adjacent to the area of Vernal Pool 3, the floodplain of the
Alberhill Creek/Collier Marsh bows out and is proximal to the vernal pool, such that it
appears that this vernal pool is more directly influenced hydrologically and historically in
its formation by the creek.
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Vernal Pool 2
Vernal Pool 2 is approximately 0.40 acre. As with Vernal Pool 1, this vernal pool is in
an area mapped as containing Willow Silty Clay soils (saline-alkali). However, Vernal
Pool 2 has a different appearance than Vernal Pool 1 in the soils and the resulting
vegetative makeup. All three vernal pools at the Project site have been disturbed in the
past and it is possible that soils underlying Vernal Pool 2 have been modified, possibly
with in-fill soils. Regardless, the vernal pool contains a strong alkaline component. A
few individuals of Coulter’s goldfields were observed on the edge of the pool; however,
the other species associated with Vernal Pools 1 and 3 were not detected in Vernal
Pool 2.
Vernal Pool 3
Vernal Pool 3 is approximately 0.63 acre. As with Vernal Pools 1 and 2, this vernal pool
is in an area mapped as containing Willow Silty Clay soils (saline-alkali). However, the
appearance (color) of the soils associated with Vernal Pool 3 suggests a lesser alkaline
component than with Vernal Pool 1, which is also reflected in the denser vegetation
within Vernal Pool 3, including a sizeable population of Coulter’s goldfields. Additional
vernal pool plant species noted in Vernal Pool 3 includes vernal barley and woolly
marbles (Psilocarphus brevissimus var. brevissimus) and alkali popcorn flower
(Plagiobothrys leptocladus).
Hydrologically, Vernal Pool 3 is different than the other two vernal pools. Drainage A is
connected to the downslope end of the pool and runoff from Drainage A helps to feed
the pool along with runoff from Baker Street, and vertical rainfall falling on the pool and
from the immediate watershed.
The Project will permanently impact up to 0.08 acre of Vernal Pool 2 (0.01 acre) and
Vernal Pool 3 (0.07 acre) along the southern edge because of constructing the storm
drain outlets along the edge of the Baker Street improvements, although much if not all
of the impacts might be temporary. As described below, the southern edge of Vernal
Pool 3 will be recontoured following the completion of construction of the Baker Street
improvements and the storm drain outlets, and the vernal pool will be part of the
Project’s proposed RCA Conserved Land. The potential impact to Vernal Pool is limited
to 0.01 acre at the southern edge, and it is expected that work limits will be adjusted in
the field under the supervision of the Project Biologist to fully avoid Vernal Pool 2.
Vernal Pools 1 will be avoided by the Project, and both Vernal Pools 1 and 2 will also be
part of the RCA Conserved Land.
Regarding indirect effects, Vernal Pool 3 is hydrologically unique compared with the
other two vernal pools, in that Vernal Pool 3 is partially fed by Drainage A, which flows
through the topographically lower end of the vernal pool. The vernal pool also receives
hydrologic input from another culvert location at the edge of Baker Street. As noted
above in the project description, the Project will construct two storm drain outlets at
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these same locations. The Project will construct the two outlets and configure the post-
Project hydrology in a manner that will mimic the existing conditions to the maximum
extent feasible. The outlets will be constructed approximately 250 feet apart from each
other and will collectively release water such that runoff will be spread between the two
outlets and into the vernal pool similar to the existing condition. The Project’s
Preliminary Drainage Report is included as Appendix G.
3.2.3 Fairy Shrimp
As noted above, a partial dry season survey was completed in 2021 for Pools 2 and 4,
with cysts of the genus Branchinecta detected in both pools [Appendix C – 2021 Dry
Season Fairy Shrimp Report]. However, a wet season survey has not yet been
performed for these features to confirm the species of Branchinecta present, and no
surveys have been performed for Pools 1 and 3. Dry season surveys have been
initiated for all four pools and the results are pending. Wet season surveys are also in
progress. To date, the versatile fairy shrimp (B. lindahli) has been detected in Pools 1
through 3 but has not yet been confirmed in Pool 4. Listed fairy shrimp have not been
detected in the pools.
It cannot yet be concluded whether the Project will impact listed fairy shrimp. This
information will be provided when both the dry season and wet season surveys have
been completed.
3.2.4 Riparian Birds
GLA biologists did not detect the southwestern willow flycatcher during the focused
surveys. A male least Bell’s vireo (presumed nesting based on behavior) was detected
within Alberhill Creek during multiple visits within close proximity to Nichols Road and
the Project’s proposed conservation. Based on the detections, the habitat with Alberhill
Creek between Nichols Road and the proposed conservation lands would be
considered occupied and have long-term conservation value for least Bell’s vireo.
The Project is not expected to directly impact riparian birds, including least Bell’s vireo.
The Project will not remove any riparian habitat, including habitat with long-term
conservation value (LTCV) for the vireo. Riparian habitat is located adjacent to Nichols
Road; however, proposed improvements adjacent to Alberhill Creek will be limited to
road re-surfacing and re-striping, with no additional widening. The remaining habitat
within the Project site is included in the proposed RCA Conserved Land. The Project is
also not expected to indirectly impact riparian birds. The onsite portion of the Project is
nearly one-quarter mile from Alberhill Creek and therefore construction and operation of
the industrial facility will not have edge effects on habitat within the Creek, including
from noise and lighting.
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3.3 Mitigation and Equivalency
3.3.1 Direct Effects
Riparian/Riverine Areas
The Project will mitigate impacts to 0.50 acre of riverine areas offsite through the
purchase of mitigation credits from the Riverpark Mitigation Bank. The mitigation credits
will include a minimum 1:1 of re-establishment and 2:1 of re-establishment and/or re-
habilitation. Since the Riverpark Mitigation Bank involves the restoration of areas
adjacent to the San Jacinto River, the mitigation bank lands provide hydrologic functions
to the San Jacinto River floodplain similar to the functions provided by drainage features
to be impacted at the Project site that are tributary to the Alberhill Creek floodplain. As
a matter of habitat replacement, the purchase of 1.50 acres of mitigation credits (1:1 of
re-establishment and 2:1 of re-establishment and/or re-habilitation) will be biologically
superior compared with the impacts.
Vernal Pools
As noted above, up to 0.08 acre of the vernal pools (0.01 acre of Vernal Pool 2 and 0.07
acre of Vernal Pool 3) will be impacted to construct the Baker Street improvements and
storm drain outlets. Following the completion of construction, the southern edge of
Vernal Pool 3 will be re-contoured and any portion of the 0.07-acre impacts that are
temporary will be restored, including revegetation coinciding with the Coulter’s goldfields
mitigation (discussed below). Although this impact area includes 0.01 acre of Vernal
Pool 2, it is expected that the work area limits will be adjusted in the field under the
supervision of the Project Biologist to fully avoid Vernal Pool 2. Any permanent impacts
to the vernal pools will be mitigated by expanding Vernal Pool 3 on the opposite side
from the impacts through recontouring and revegetating. The vernal pool will be
expanded by at least a 3:1 ratio versus the permanent impacts. Assuming up to 0.08-
acre permanent impacts, the vernal pool will be expanded by 0.25 acre. A HMMP will
be prepared to address the vernal pool mitigation, including site preparation, non-native
plant removal (if applicable), maintenance, success criteria, and monitoring. The
monitoring will include hydrologic monitoring to confirm that the recontoured areas
inundate sufficiently to support wetland conditions. The HMMP will be provided to the
RCA and Wildlife Agencies for review and approval. The proposed mitigation will be
subject to approval through the DBESP process, in addition to JPR.
Fairy Shrimp
As the results of fairy shrimp surveys are pending, it cannot yet be determined whether
mitigation will be required for impacts to listed fairy shrimp. If listed fairy shrimp are
detected in one or more pools to be impacted, then an avoidance analysis will be
performed to determine if at least 90% of habitat with LTCV can be avoided. If the
proposed Project cannot demonstrate at least 90% avoidance (permanent and
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temporary) of occupied portions of the site that provide habitat with LTCV, impacts must
be approved through the DBESP process whereby mitigation would demonstrate
equivalent or superior function and value. Avoidance of habitat with LTCV would also
include avoidance of supporting hydrology. Per the MSHCP, not all habitat must be
occupied for it to be considered to have LTCV. At a minimum, details of the mitigation
would include the location of mitigation area, type of mitigation, acreages, when the
mitigation would be implemented, success criteria, monitoring plan (e.g., years/duration,
frequency, etc.), reporting, the management entity, and contingency plan in the event
the mitigation is not successful. In addition, mitigation areas for fairy shrimp would need
to be protected in perpetuity.
Riparian Birds
The Project is not expected to impact habitat for riparian birds, including habitat with
LTCV for least Bell’s vireo. Therefore, mitigation will not be required for riparian birds.
3.3.2 Indirect Effects
The Project is designed to avoid or otherwise minimize indirect effects to sensitive
MSHCP resources. The focus of the analysis is on hydrologic effects to the vernal
pools located in the adjacent proposed RCA Conserved Land, and downstream aquatic
resources in the Alberhill Creek, as well as the effects of noise and lighting on adjacent
RCA Conserved Land.
Hydrology Effects
The Project’s Preliminary Drainage Report (Drainage Report) is referenced here
[Appendix G] in addressing the potential hydrologic effects of the Project for the 2-, 5-,
10-, and 100-year condition. The Drainage Report identifies four Drainage Areas (A
through D) for the Project site and the Project will construct storm drain outlets at four
locations corresponding to these Drainage Areas. Appendix C of the Drainage Report
(PDF page 54) depicts the Project’s existing condition and includes an Existing
Condition Hydrology Map identifying the four Drainage Areas where the outlets are
proposed. Appendix D of the Drainage Report (PDF page 122) provides the proposed
condition. Drainage Area A will outlet into a proposed two 36-inch RMP, Drainage Area
B will outlet into a proposed 36-inch RMP, Area C will outlet into a proposed 36-inch
RMP, and Area D will outlet into a proposed two 36-inch RMP. According to Section 2.5
of the Drainage Report, the outlet velocity at each location shall be at or below the
existing condition or to a non-erosive velocity.
Post-project, Drainage Area A will outlet on the northern side of the proposed Baker
Street improvements into the Project’s proposed RCA Conserved Lands. There are no
stream or other sensitive resources at this location, but the topography consists of a
swale area that extends offsite towards the Alberhill Creek floodplain. Drainage Area B
will outlet on the northern side of the proposed Baker Street improvements at Vernal
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Pool 1 within the proposed RCA Conserved Lands. Drainage Area C and D will each
separately outlet north of the Baker Street improvements at Vernal Pool 3. The two
outlets will be constructed in a manner where flows from both will feed into the vernal
pool watershed at the “upstream” end.
Based on the hydrology data from the Drainage Report, the following table (Table 3-5)
compares the existing and proposed conditions for peak flows in Drainage Areas A
through D for the 2-, 5-, 10-, and 100-year events.
Table 3-5. Summary of Peak Flows Existing Versus Proposed (in cfs)
Drainage Area A
Condition Q2 Q5 Q10 Q100
Existing 84.23 132.10 197.59 332.50
Proposed 76.48 119.63 178.35 299.61
Change -7.75 -12.47 -19.24 -32.89
Drainage Area B
Condition Q2 Q5 Q10 Q100
Existing 21.19 32.46 46.47 77.05
Proposed 34.97 51.08 67.45 110.00
Change +13.78 +18.62 +20.98 +32.95
Drainage Area C
Condition Q2 Q5 Q10 Q100
Existing 15.83 24.29 35.01 60.15
Proposed 34.35 48.91 62.57 100.41
Change +18.52 +24.62 +27.56 -18.79
Drainage Area D
Condition Q2 Q5 Q10 Q100
Existing 106.37 166.04 258.99 428.57
Proposed 97.18 151.53 237.02 391.60
Change -9.19 -14.51 -21.97 -36.97
Drainage Area C and D will both outlet at the edge of Vernal Pool 3 approximately 100
feet apart and in similar locations compared with the existing condition. Flows from the
two outlets will spread together into the adjacent vernal pool. As such, the two
Drainage Areas should be viewed together with regards to changes in peak flows.
Combined, the two drainage areas will result in an overall increase for the 2-, 5-, and
10-year events, with a decrease in the 100-year event. Drainage Area B and C will
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have onsite detention to mitigate for any increase in runoff. The proposed condition will
mimic the existing condition at each discharge location. Table 3-6 summarizes the
change in peak flows for the for the combined Drainage Areas.
Table 3-6. Summary of Peak Flows Existing Versus Proposed (in cfs)
Drainage Areas C and D
Condition Q2 Q5 Q10 Q100
Existing 122.20 190.33 294.00 488.72
Proposed 131.53 200.44 299.59 492.07
Change +9.33 +10.11 +5.59 -55.76
Lighting
Night lighting shall be directed away from the MSHCP Conservation Area to protect
species within the MSHCP Conservation Area from direct night lighting. If night lighting
is required during construction, shielding shall be incorporated to ensure ambient
lighting in the MSHCP Conservation Area is not increased.
The Project will incorporate an onsite lighting design that provides the required lighting
levels for normal operation onsite. Exterior lighting can be designed as downward
facing to prevent unnecessary foot candles outside of the Project boundary. The City of
Lake Elsinore requires public streetlights every 200 feet on both sides of newly
constructed public roadways per Lake Elsinore standards 503 and 508. The Project will
work with the City to design a public roadway lighting design that is sensitive to
neighboring sensitive receptors.
Noise
Proposed noise generating land uses affecting the MSHCP Conservation Area shall
incorporate setbacks, berms, or walls to minimize the effects of noise on MSHCP
Conservation Area resources pursuant to applicable rules, regulations and guidelines
related to land use noise standards. For planning purposes, wildlife within the MSHCP
Conservation Area should not be subject to noise that would exceed residential noise
standards.
The Project is not expected to adversely affect wildlife in the adjacent/proximal
Conservation Area due to noise. The onsite portion of the Project is buffered from the
proposed RCA Conserved Lands by the Baker Street improvements. Additionally, the
proposed Conserved Lands adjacent to the development footprint does not contain
habitat that would support wildlife sensitive to noise effects. The portion of existing
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Nichols Road that crosses Alberhill Creek is adjacent to habitat occupied by least Bell’s
vireo and other riparian birds. The proposed re-surfacing will either be performed
outside of the vireo season, or if work is performed during the vireo season, then noise
attenuation measures will be implemented, if needed.
4.0 NARROW ENDEMIC PLANT SPECIES MITIGATION (SECTION 6.1.3)
4.1 Methods
Volume I, Section 6.1.3 of the MSHCP requires that within identified Narrow Endemic
Plant Species Survey Areas (NEPSSA), site-specific focused surveys for Narrow
Endemic Plants Species will be required for all public and private projects where
appropriate soils and habitat are present. The Project site occurs within the NEPSSA for
the following target species:
· Munz’s onion (Allium munzii)
· San Diego ambrosia (Ambrosia pumila)
· Slender-horned spineflower (Dodecahema leptoceras)
· Many-stemmed dudleya (Dudleya multicaulis)
· Spreading navarretia (Navarretia fossalis)
· California Orcutt grass (Orcuttia californica)
· San Miguel savory (Clinopodium chandleri)
· Hammitt’s clay-cress (Sibaropsis hammittii)
· Wright’s trichocoronis (Trichocoronis wrightii var. wrightii).
GLA biologists performed general and focused plant surveys for the Project site in both
2020 and 2022. GLA biologists Jillian Stephens and David Moskovitz performed plant
surveys for most of the onsite part of the Project on April 13, and 23, and May 5 and 20,
2020, as well as for the proposed RCA Conserved Land. In 2022, GLA biologists Jillian
Stephens and Wanisa Jaikwang repeated surveys for the onsite portion, including
expanded areas that were not surveyed in 2020, as well as the offsite components. The
2022 surveys were conducted on March 14, April 4 and 6, and May 3, 2022. Surveys
were conducted in accordance with accepted botanical survey guidelines (CDFW 2018,
CNPS 2001, Nelson 1984, USFWS 2000). As applicable, surveys were conducted at
appropriate times based on precipitation and flowering periods. An aerial photograph, a
soil map, and/or a topographic map were used to determine the community types and
other physical features that may support sensitive and uncommon taxa or communities
within the Project site. Surveys were conducted by following meandering transects
within target areas of suitable habitat. All plant species encountered during the field
surveys were identified and recorded following the above-referenced guidelines. A
complete list of the plant species observed is provided in Appendix A. Scientific
nomenclature and common names used in this report follow Baldwin et al. (2012), and
Munz (1974).
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4.2 Results/Impacts
One Narrow Endemic Plant species (San Diego ambrosia) was detected at the Project
site. The majority of plants within the Project site were at two locations in the southern
end of the site. Additional locations with fewer numbers of plants included one location
in the central portion of the site, three locations adjacent to Pierce Street, and one
location adjacent to Nichols Road [Exhibit 7 – Rare Plants Map]. GLA biologists
estimated 9,000 plants over 0.44 acre of habitat with long-term conservation value for
the species. These locations of San Diego ambrosia within the Project site have been
previously documented in the public record by other botanists, including by Steve Boyd
(1997) and A.C. Sanders (2014 and 2015). Other locations within the Project site
(within the RCA Conserved Lands) were documented by F.M. Roberts (1997), D.E.
Bramlet (1997), and Mitch Provance (2005).
The Project will impact San Diego ambrosia in several locations, including in the
southern portion of the Industrial footprint (onsite) and within the proposed offsite road
improvements along Pierce Street and Nichols Road. Because the Project site is within
the NEPSSA for San Diego ambrosia, the Project is required by the MSHCP to identify
habitat with long-term conservation value for the species and to avoid at least 90
percent of the habitat. GLA has identified 0.44 acre of habitat with long-term
conservation value for the ambrosia within the Project footprint, all of which will be
impacted by the Project. As such, a DBESP must be approved to authorize impacts to
San Diego ambrosia.
4.3 Mitigation and Equivalency
4.3.1 Direct Effects
All impacts to plant habitat with long-term conservation value will be mitigated within the
proposed RCA Conserved Lands. To mitigate the loss of 0.44 acre of habitat with long-
term conservation value for San Diego ambrosia, the Project will restore approximately
1.25 acres of degraded habitat in the Alberhill Creek floodplain with San Diego
ambrosia [Exhibit 10 – Plant Restoration Map]. The proposed restoration area consists
of an area dominated by non-native grasses and forbs where San Diego ambrosia was
detected in the past (per public records), but where due to overgrowth by invasive
vegetation, San Diego ambrosia was not detected during plant surveys for the Project.
The Project will develop a HMMP that will identify site preparation methods, the
proposed plant palette, proposed success criteria, and maintenance/long-term
monitoring procedures. The HMMP will be submitted to the City, RCA, USFWS, CDFW
and the Regional Board for review and approval prior to implantation of the proposed
mitigation.
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4.3.2 Indirect Effects
The Project will not indirectly affect Narrow Endemic Plants. Besides the San Diego
ambrosia that will be directly impacted by the Project, there is no adjacent ambrosia or
other NEPSSA species that would be impacted. As noted above, the Project proposes
to mitigate the direct impacts to ambrosia in the Alberhill Creek floodplain. The
proposed mitigation area is far enough removed from the development footprint that
indirect impacts are not expected. As discussed above in Section 3.3.2, the Project is
designed such that the proposed hydrologic condition will mimic the existing condition
such that indirect effects are not anticipated.
5.0 ADDITIONAL SURVEY NEEDS (SECTION 6.3.2)
5.1 Criteria Area Species Survey Area - Plants
Note that there are no survey areas for these designated plant species outside of the
MSHCP Criteria Area.
5.1.1 Methods
The Project site occurs within the CAPSSA for the following target species:
· Thread-leaved brodiaea (Brodiaea filifolia)
· Davidson’s saltscale (Atriplex serenana var. davidsonii)
· Parish’s brittlescale (Atriplex parishii)
· Smooth tarplant (Centromadia pungens spp. laevis)
· Round-leaved filaree (California macrophylla)
· Coulter’s goldfields (Lasthenia glabrata ssp. coulteri)
· Little mousetail (Myosurus minimus ssp. apus)
GLA biologists performed general and focused plant surveys for the Project site in both
2020 and 2022. GLA biologists Jillian Stephens and David Moskovitz performed plant
surveys for most of the onsite part of the Project on April 13, and 23, and May 5 and 20,
2020, as well as for the proposed RCA Conserved Land. In 2022, GLA biologists Jillian
Stephens and Wanisa Jaikwang repeated surveys for the onsite portion, including
expanded areas that were not surveyed in 2020, as well as the offsite components. The
2022 surveys were conducted on March 14, April 4 and 6, and May 3, 2022. Surveys
were conducted in accordance with accepted botanical survey guidelines (CDFW 2018,
CNPS 2001, Nelson 1984, USFWS 2000). As applicable, surveys were conducted at
appropriate times based on precipitation and flowering periods. An aerial photograph, a
soil map, and/or a topographic map were used to determine the community types and
other physical features that may support sensitive and uncommon taxa or communities
within the Project site. Surveys were conducted by following meandering transects
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within target areas of suitable habitat. All plant species encountered during the field
surveys were identified and recorded following the above-referenced guidelines. A
complete list of the plant species observed is provided in Appendix A. Scientific
nomenclature and common names used in this report follow Baldwin et al. (2012), and
Munz (1974).
5.1.2 Results/Impacts
GLA biologists detected two Criteria Area Plant species at the Project site, including
Coulter’s goldfields and San Jacinto Valley crownscale. However, the crownscale is not
a target species for the CAPSSA that the Project site is located in. Therefore, the
Project is not required to address potential impacts to the crownscale.
Coulter’s goldfields was detected in several locations within the Project site, including
the three vernal pools as well as locations within the proposed RCA Conserved Lands
near Alberhill Creek. The majority of Coulter’s goldfields were associated with Vernal
Pool 1 and 3 [Exhibit 9 – Rare Plants Map]. GLA biologists estimated 9,000 plants over
2.51 acres of total habitat with long-term conservation value. The locations of Coulter’s
goldfields within the Project site have been previously documented in the public record
by other botanists, including by A.C. Sanders (2008), D.E. Bramlet, R.L. Allen and F.M.
Roberts (2011), and Mitch Provance (2005 and 2017)3.
In addition to Coulter’s goldfields, Mitch Provance also documented little mousetail in
2017. The UCR record describes mousetail occurring with other vernal pool indicator
plants in a pool adjacent to Baker Street. GLA did not observed a pool at the location
noted by the mousetail record. However, as GLA noted Coulter’s goldfields in Vernal
Pool 3, which is near the location shown for the mousetail record, then it is possible that
mousetail is present in that pool but was not detected by GLA during focused surveys.
The Project will impact Coulter’s goldfields associated with the one of the vernal pools
adjacent to the proposed Baker Street improvements due to the proposed storm drain
outlets and proposed maintenance area. Because the Project site is within the
CAPSSA for Coulter’s goldfields, the Project is required by the MSHCP to identify
habitat with long-term conservation value for the species and to avoid at least 90-
percent of the habitat. GLA has identified 2.61 acres of habitat with long-term
conservation value for Coulter’s goldfields associated with the three vernal pools. The
proposed Project will directly impact 0.50 acre of the habitat (20 percent) of the habitat
at the edge of one of the vernal pools. As such, a DBESP must be approved to
authorize impacts to Coulter’s goldfields.
3 CCH2 Portal. 2023. https://cch2.org/portal/index.php. Accessed on 12/11/23. University of California,
Riverside Herbarium Record.
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It is assumed that the Project might impact little mousetail based on the prior public
record of detection. Impacts are assumed up to 0.07 acre of habitat with long-term
conservation value based on proposed impacts to Vernal Pool 3. As such, a DBESP
must be approved to authorize impacts to little mousetail.
5.1.3 Mitigation and Equivalency
To mitigate the loss of 0.50 acre of habitat with long-term conservation value for
Coulter’s goldfields, the Project will restore/expand Coulter’s goldfields habitat in two
areas. The first area consists of the expansion of Vernal Pool 3 by approximately 0.75
acre [Exhibit 10 – Plant Restoration Map]. The expansion of Vernal Pool 3 would also
mitigate assumed impacts to little mousetail. The second area consists of the
expansion of another 0.75-acre area in the Alberhill Creek floodplain adjacent to an
existing population of Coulter’s goldfields and vernal barley. The Project will develop a
HMMP that will identify site preparation methods, the proposed plant palette, proposed
success criteria, and maintenance/long-term monitoring procedures. The HMMP will be
submitted to the City, RCA, USFWS, CDFW and the Regional Board for review and
approval prior to implantation of the proposed mitigation.
5.2 Burrowing Owl
5.2.1 Methods
The Project site is within the survey area for the burrowing owl (Athene cunicularia).
As such, the MSHCP requires that the Project evaluate impacts to the burrowing owl
through habitat assessments/focused surveys.
Focused surveys are required to be conducted pursuant to the 2006 MSHCP Burrowing
Owl Survey Instructions. The Burrowing Owl Survey Instructions are divided into three
components, including Step I (habitat assessment), Step II-A (focused burrow survey),
and Step II-B (focused burrowing owl survey). The guidelines stipulate four focused
survey visits (Step II-B) be conducted on separate dates between March 1 and August
31.
GLA initially evaluated most of the proposed development footprint for burrowing owls in
2020, including the Step I habitat assessment and preliminary burrow mapping (Step II-
A). GLA biologist David Smith performed visits on April 16 and 28, 2020. The entire
Project site was evaluated for burrowing owls in 2022, including approximately 75 acres
of potentially suitable habitat that was subject to focused burrowing owl surveys (Step II-
B). Step II-B of the Survey Instructions requires a minimum of four survey visits,
indicating that a single biologist should not survey more than 100 acres per day. As the
survey area for the Project consisted of 75 acres, the area could be covered by a single
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biologist in one day. GLA biologist Stephanie Cashin performed the focused owl
surveys on March 9, April 4, May 2, and June 3, 2022.
The burrowing owl survey visits are to be conducted during a period from one hour prior
to sunrise to two hours after sunrise or two hours before sunset to one hour after
sunset. All survey visits were conducted in the morning within the allotted timeframe.
The surveys were conducted during weather that was conducive to observing owls
outside their burrows and detecting burrowing owl sign, and not during rain, high winds
(> 20 mph), dense fog, or temperatures over 90 °F. Table 5-1 summarizes the focused
burrowing owl surveys conducted for the Project.
Table 5-1. Summary of Burrowing Owl Surveys
Survey Date Biologist(s) Survey
Period
Time
Start/End
Temperature
(°F)
Start/End
Wind Speed
(mph)
Cloud
Cover
(%)
3/9/2022 SC 0600/0815 40/54 0-2 0
4/4/2022 SC 0600/0805 51/58 0-3 0
5/2/2022 SC 0600/0830 57/63 0-1 0
6/3/2022 SC 0600/0810 55/60 0-1 50
SC = Stephanie Cashin
Surveys were conducted by walking meandering transects throughout areas of suitable
habitat. Exhibit 11 identifies the burrowing owl survey areas at the Project site,
including a 500-foot visual survey area around the Project site. Transects were spaced
at a maximum of 30 meters (100 feet) apart from each other, adjusting for vegetation
height and density, to provide adequate visual coverage of the survey areas. At the
start of each transect, and at least every 100 meters along the transects, the survey
area was scanned for burrowing owls using binoculars. All suitable burrows were
inspected for diagnostic owl sign (e.g., pellets, prey remains, whitewash, feathers,
bones, and/or decoration) to identify potentially occupied burrows. The 500-foot visual
survey area was at least inspected with binoculars but was also accessed on foot where
feasible. The results of the burrowing owl surveys are documented in Section 4.0 of this
report.
5.2.2 Results/Impacts
No burrowing owls were detected within the Project site during focused surveys. Exhibit
11 provides the locations of areas surveyed, including approximate transect locations as
well as the locations of suitable burrows that were mapped. Burrows were scattered
throughout the onsite portion of the Project, with many concentrated along a fence line
within the proposed RCA Conserved Land. No burrowing owl sign was observed at any
of the burrows within the disturbance limits, but a single owl pellet was observed at a
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burrow within the RCA Conserved Land along the fence line. It was not clear how old
the pellet was but given the lack of other sign and that no owls were observed during
the surveys, the pellet likely indicates a transient owl that was not occupying the site
during the focused surveys.
Based on the absence of burrowing owls within the disturbance limits, the Project will
not impact habitat with long-term conservation value.
5.2.3 Mitigation and Equivalency
Although burrowing owls were not detected during focused surveys, because the site
has the potential to support burrowing owls, pre-construction surveys will be required to
prevent harm to burrowing owls, should individuals occupy the site in the future. The
following burrowing owl measure will apply to the Project:
· Pre-construction burrowing owl surveys will be conducted in areas of suitable
habitat not more than 30 days prior to the initiation of ground disturbance (e.g.,
vegetation clearing, clearing and grubbing, tree removal, site watering, equipment
staging, grading, etc.) to ensure that no owls have colonized the site in the days or
weeks preceding the ground-disturbing activities. If burrowing owls have colonized
the project site prior to the initiation of ground-disturbing activities, the project
proponent will immediately inform the Regional Conservation Authority (RCA) and
the Wildlife Agencies and will need to coordinate further with RCA and the Wildlife
Agencies, including the possibility of preparing a Burrowing Owl Protection and
Relocation Plan, prior to initiating ground disturbance. If ground-disturbing
activities occur, but the site is left undisturbed for more than 30 days, a pre-
construction survey will again be necessary to ensure burrowing owl has not
colonized the site since it was last disturbed. If burrowing owl is found, the same
coordination described above will be necessary.
5.3 Mammals
The Project site is not located within a mammal survey area. As such, focused surveys
are not required for designated mammal species and there are no other requirements
applicable to the Project for mammals.
5.4 Amphibians
The Project site is not located within an amphibian survey area. As such, focused
surveys are not required for designated amphibian species and there are no other
requirements applicable to the Project for amphibians.
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6.0 DELHI SANDS FLOWER-LOVING FLY
The Project site is not located within Delhi soils mapped within the MSHCP baseline
data, and therefore habitat assessments/focused surveys are not required for the Delhi
Sands flower-loving fly (Rhaphiomidas terminatus abdominalis).
7.0 REFERENCES
Sogge, M.K, Ahlers, D., and Sferra, S.J. 2010. A Natural History Summary and Survey
Protocol for the Southwestern Willow Flycatcher: U.S Geological Survey
Techniques and Methods 2A-10, 39p.
https://www.fws.gov/ventura/endangered/species/surveys-protocol.html
USFWS. 2001. Least Bell’s Vireo Survey Guidelines. January 19, 2001. Sacramento,
California: USFWS.
https://www.fws.gov/cno/es/Recovery_Permitting/birds/least_bells_vireo/
LeastBellsVireo_SurveyGuidelines_20010119.pdf
USFWS. 2016. A Natural History Summary and Survey Protocol for the Western
Distinct Population Segment of the Yellow-Billed Cuckoo. Prepared by M.
Halterman, M.J. Johnson, J.A. Holmes, and S.A. Laymon. Sacramento,
California: USFWS. May 2016.
https://www.fws.gov/southwest/es/arizona/Documents/SpeciesDocs/YellowBilled
Cuckoo/YBCU%20Survey%20Protocol_%20DRAFT_2016.pdf