HomeMy WebLinkAboutMASON STREET INFRASTRUCTURE PROJECT - FDP230016 - SUBMITTAL DOCUMENTS - ROUND 6 - Supporting Documentation (6)
Mason Street Infrastructure
Native Habitat Buffer Zone Restoration and Annual
Monitoring Plan
March 2024
Revised April 2024
PO Box 272150
Fort Collins, CO 80527
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Table of Contents
1.0 Introduction ................................................................................................................................ 1
2.0 Existing Site Conditions ................................................................................................................ 2
3.0 Restoration Plan .......................................................................................................................... 3
3.1 Goals and Objectives .............................................................................................................. 3
3.2 Step-by-Step Approach........................................................................................................... 5
4.0 Annual Monitoring Plan .............................................................................................................. 12
4.1 Schedule ............................................................................................................................. 12
4.2 Permanent Photo-points ....................................................................................................... 12
4.3 Sampling Methodology ......................................................................................................... 13
4.4 Success Criteria ................................................................................................................... 13
5.0 Literature Cited and Data Sources .............................................................................................. 15
1.0 INTRODUCTION
North College 1311, LLC has proposed the Mason Street Infrastructure development project (“site”) within
3 lots totaling approximately 13.13 acres. The City of Fort Collins (City) has also proposed a future detention
basin (“Hickory Pond”) within portions of Lot 1 and 2 within the site. The site is located within parcels
9702100007 and 9702100918 and is situated between Willox Lane and Hickory Street to the north/south,
with Mason Street to the east and railroad to the west.
An Ecological Characterization Study (ECS) was performed in September 2022 as required by Article 3,
Section 3.4.1 of the City Land Use Code (LUC) (Cedar Creek 2023). The ECS informed the City’s
determination that the site contains Dry Creek and will require the implementation of a Natural Habitat
Buffer Zone (NHBZ) to mitigate potential impacts from development on ecological character and quality.
The proposed Project Development Plan presents the NHBZ delineations on site in accordance with LUC
guidelines. Approval of the proposed NHBZ delineation is contingent upon the Applicant completing
additional mitigation requirements prescribed by the City’s Environmental Planning Department.
This NHBZ Restoration and Annual Monitoring Plan (Plan) presents recommended restoration and
monitoring approaches which have been designed to ascertain measurable habitat improvement in the
NHBZ. The objective of this Plan is to describe the methods and procedures that will be used to implement
restoration, assess establishment and progress of restoration, identify potential issues, and gather
information used to inform adaptive management activities. Weed management is discussed within the
broader context of our proposed approach in this document and detailed more specifically in a separate
Weed Management Plan (Cedar Creek 2024).
2.0 EXISTING SITE CONDITIONS
The site primarily consists of upland grassland, containing a mixture of native, invasive, and noxious
species, dominated by smooth brome (Bromus inermis). Other species include leafy spurge (Euphorbia
esula), Canada thistle (Cirsium arvense), Western wheatgrass (Pascopyrum smithii), orchard grass (Dactylis
glomerata), alfalfa (Medicago sativa), and prickly lettuce (Lactuca serriola). Dry Creek traverses the site
from the northwest to the southeast. Dry Creek appears to contain no active surface hydrology and shows
little signs of conveying ephemeral flow.
As such the Dry Creek riparian area is dominated by Siberian elm (Ulmus pumila), crack willow (Salix
fragilis), and white poplar (Populus alba), with a herbaceous layer dominated by smooth brome. Other
species include showy milkweed (Asclepias speciosa), horse tail (Equisetum sp.), rose (Rosa woodsii), wild
licorice (Glycyrrhiza lepidota), and narrowleaf willow (Salix exigua). The southeast portion of Dry Creek
(across Mason Street) is dominated by cottonwood (Populus deltoides) and contains no herbaceous layer.
Dry Creek is listed as requiring a 100-foot NHBZ in Section 3.4.1 of the City LUC.
Given that Dry Creek has not exhibited flowing water for a long time, it is likely that existing vegetation is
dependent on shallow ground water. Therefore, the established trees and shrubs within the riparian zone
likely will not need supplemental irrigation. However, if additional plant materials are installed supplemental
temporary irrigation is warranted.
3.0 RESTORATION PLAN
3.1 Goals and Objectives
In accordance with the City LUC 3.4.1 the NHBZ should be managed to:
1. Preserve or enhance the ecological character or function and wildlife use of the natural habitat or
feature and to minimize or adequately mitigate the foreseeable impacts of development.
2. Preserve or enhance the existence of wildlife movement corridors between natural habitats and
features, both within and adjacent to the site.
3. Enhance the natural ecological characteristics of the site. If existing landscaping within the NHBZ
is determined by the decision maker to be incompatible with the purposes of the buffer zone, then
the applicant shall undertake restoration and mitigation measures such as re -grading and/or the
replanting of native vegetation.
4. Provide appropriate human access to natural habitats and features and their associated NHBZ’S in
order to serve recreation purposes, provided that such access is compatible with the ecological
character or wildlife use of the natural habitat or feature.
More specific goals have been established through meetings with the City. These general goals are:
1. Control weeds prior to construction throughout the site, including the Dry Creek riparian corridor.
2. Focus on the enhancement of the Dry Creek riparian corridor through potential direction of sheet
flow of hydrology on site within Dry Creek and additional herbaceous, shrub, and tree plantings.
3. The future Hickory Pond should resemble a naturalized wetland and shrub plantings around the
fringe of the pond should be included.
4. The remaining mitigation area should be established into a higher quality upland grassland than
the existing habitat.
The restoration approach and monitoring presented in this Plan has been developed to support the meeting
of NHBZ goals through evaluation of revegetation establishment and progression. Monitoring results can
be used to identify problem areas or potential issues early in the restoration process, inform adaptive
management activities (i.e., weed management), and assess progress towards the meeting of success
criteria indicative favorable NHBZ restoration and management.
3.2 Responsiblities
The applicant shall be responsible for:
• Restoration of all upland portions of the NHBZ, including the upland portions of the NHBZ that
occur on City of Fort Collins property. The applicant is expected to meet the upland restoration
requirements prior to the handoff to City of Fort Collins Utilities.
• Preservation and enhancement of the remnant Dry Creek, including establishing site grading to
encourage water infiltration within the remnant Dry creek to the maximum extent possible.
• Restoration of the Hickory Regional Detention Pond to the interim condition, where the established
vegetation will provide soil surface stability until the final design and restoration is completed by
the City of Fort Collins Utilities.
City of Fort Collins Utilities shall be responsible for:
• Ongoing maintenance and weed management of all upland portions of the NHBZ on City of Fort
Collins property, after the applicant has met the establishment requirement on the upland portions
of the NHBZ.
• Final restoration of the Hickory Regional Detention Pond, including installation of naturalized
wetland features within the ordinary high-water mark of the detention pond. Hickory Regional
Detention Pond shall mimic a heterogeneous natural stream/wetland/floodplain complex as much
as site constraints allow. The primary function of the design should attenuate flows and mimic the
former Dry Creek riparian complex of riparian corridor, wetlands, and floodplain of the former Dry
Creek.
o Increase the pervious surface area across the basin’s bottom.
o Slow water flow and dissipate flow concentration.
o Emphasize sinuous edges and an undulating bottom in order to maximize heterogeneity of
edge habitats and provide more resistance to flow through small islands, oxbow channel
mimics, and mini floodplains.
o Minimize Edge Slope: The terrestrial- facultative plant boundary should have a very gradual
slope.
o Persistent Emergent Vegetation: Persistent emergent vegetation has stems which persist
even after the growing season. This provides year-round resistance to water flow.
o Create a heterogeneous moisture regime with hydric, mesic, and upland communities.
The design criteria for the Hickory Regional Detention Pond shall include topography to support a
variety of hydric conditions, which will result in planned water dependent vegetative communities
ranging from emergent / mesic meadow with obligate and facultative wetland species, which will
transition to riparian / mesoriparian / xeroriparian habitats where facultative willows and shrubs
can be planted. Plant materials, in the form of seeding and planting , will be used to restore habitat
features within the detention pond and should target structural and species diversity.
3.3 Step-by-Step Approach
The following is a recommended step-by-step process designed to reduce cost, improve the ecological
function, and enhance the ecological characteristics of the NHBZ while maintaining flexibility for site-specific
conditions.
Step 1. Creating Opportunity and Reducing Competition
Noxious and invasive species are often non-native, aggressive spreaders, that dominate an ecosystem and
outcompete native species. Establishing native species is important for restoration goals and to provide
healthy, diverse, and sustainable ecosystem. If noxious and invasive species are left unmanaged,
opportunities for native species establishment are greatly reduced. It is recomme nded some method of
vegetation control must be utilized to control noxious and invasive species.
Vegetation control is implemented via mechanical or chemical controls. Mechanical control entails scraping
or plowing to increase bare ground exposure which will serve as a seedbed / planting medium. Chemical
control entails the use of herbicide to diminish dominance of undesirable and noxious species . Leafy spurge
and Canada thistle the dominant noxious species on the site (see Weed Management Plan; Cedar Creek
2024). The dominant invasive species within the site is smooth brome, an aggressive, non-native, perennial
and rhizomatous grass, spread by wind-driven cross-fertilization to produce seeds and propagate
vegetatively through tillering and root fragments. While smooth brome can negatively impact biodiversity,
it does provide excellent soil stability and forage potential for wildlife. Therefore, a total eradication of this
species may not be necessary, but a chemical treatment is highly recommended prior to initiating
mechanical manipulation of soil, to reduce competition and encourage the establishment of native
vegetation.
Step 2. Grading
Current development plans propose filling in portions of Dry Creek, though a majority of the channel will
remain intact. Grading will be completed to ensure some surface water flows will continue to contribute to
the remnant portions of Dry Creek. Grading and design of the future Hickory Pond should follow the City’s
standards and guidelines (City of Fort Collins 2009 & 2018).
Prior to the commencement of grading, the contractor shall be required to show proof of equipment
cleaning. The mechanism for showing proof should be agreed upon between the contractor and the City
of Fort Collins Environmental Planning before implementation of the grading.
Step 3. Soil Preparation
The soil surface should be optimized for seeding or planting. An agronomic assessment is recommended
to evaluate the chemical and physical properties of the soil throughout the site, and a required design
standard in the location of the proposed Hickory Pond. This information can be used to determine whether
soil amendments (i.e. compost) would benefit the establishing plant communities and allow for optimization
of the seed mix to soil conditions.
Planted areas in Hickory Pond will require topsoil with appropriate levels of organic matter and should
receive imported or stockpiled topsoil to a minimum depth of four inches. Sub-grade should be loosened
to a depth of 12 inches total (8” existing sub-grade and 4” of new topsoil) in Hickory Pond and 10 inches
throughout the remainder of the site. Stones, clods, sticks, rubbish, and other matter large enough to
impede planting, seeding, or mowing should be collected and removed from the site. Removed material
must be disposed of legally.
Cultivation should be repeated in areas where equipment used for hauling and spreading topsoil has
recompacted the soil. Disturbed areas should be fine graded to a smooth, uniform surface plane. Prior to
seeding, the soil surface should be loose, allowing for good soil/seed contact. Roll and rake, remove ridges,
and fill depressions to meet surface grades based on grading plans.
Prior to seeding an Environmental Planning inspector needs to confirm proper seed bed preparation and
seed mix details are appropriate.
Step 3. Seeding and Planting
Seeding and planting should occur as soon as possible following final construction and final contouring
within a suitable time frame. For seeding, late fall to early spring (October to May) is favorable, with late
fall being priority for non-irrigated areas. Woody plantings should occur in late fall (prior to frozen ground)
or early spring (October to May) to increase survival success. Woody planting being planted from containers
should have the sides and bottom of the root system scarified. Live stakes sho uld be installed to ensure 70
to 80% of the entire live stake is underground.
The species used should be native and suitable to the soil and moisture conditions of the NHBZ. Seed mixes
should be designed to facilitate growth of appropriate and sustainable species. If changes are to be made
to the proposed seed mix based on site conditions, then approval must be provided by a city Environmental
Planner. The proposed seed mixes are based on the City’s recommended species, site conditions, and the
U.S. Army Corps of Engineers (USACE) Wetland Indicator Status Plant List for the Great Pla ins Region
(USACE 2020). The site contains a high-water table within areas, notably the Dry Creek area. A mixture of
upland, facultative-upland, facultative, facultative-wetland, and obligate species were selected to represent
varying conditions and slopes. Species were also selected to provide pollinator habitat, with emphasis on
milkweed species for the U.S. Fish and Wildlife Service (USFWS) federal listing candidate, the monarch
butterfly (Danaus plexippus). See Table 1 for a Proposed Hickory Pond Seed Mix and Table 2 for Proposed
Upland Grassland Seed Mix.
Seeding can be accomplished using broadcasting and drilling techniques wherever applicable.
• For broadcast seeding: the seeding rate should be doubled, seed-to soil contact should be increased
immediately through manipulation which will also provide some protection from wind or water
erosion and granivores. Manipulation can be accomplished by either a light disc harrowing
perpendicular to the flow of energy (wind and/or water) or hand raking around sensitive areas (i.e.
willow patches).
• For drill seeding, final drilling pass must occur on the contour, to create subtle ridges perpendicular
to the flow of energy. Drill seeding should not be conducted in sensitive areas.
Appropriate native seeding equipment will be used, which does not include standard turf seeding equipment
or agriculture equipment. Drill seed the approved mix in two passes, each at a right angles to the other
and using half the seed in each pass. Seed should be drilled at the specified application rate and to a depth
of no greater than ½ inch. If areas are too wet or steep to drill seed, broadcast seed in opposite directions
at twice the application rate used for drill seeding. Restore fine grade after seeding, and cover seed to a
depth of ¼ of an inch by raking or dragging. Firm seeded areas with a roller weighing a maximum of 100
lbs. per foot of width.
Woody plantings of trees and shrubs along Dry Creek and the fringe of Hickory Pond are also proposed to
provide structural diversity and meet restoration goals. Species to be used should be approved by a City
Environmental Planner. Woody plantings should be planted using industry Best Management Practices.
The following native trees are recommended for planting:
• Cottonwood (Populus deltoides). This species is present within portions of Dry Creek, except in
areas where non-native or noxious species such as Siberian elm and crack willow are present.
Cottonwood should be planted along Dry Creek where possible.
• Peachleaf willow (Salix amygdaloides). This species may be planted along Dry Creek and along the
fringe of Hickory Pond.
The following upland native shrubs are recommended for planting along the fringe of Hickory Pond or other
upland areas:
• Rubber Rabbitbrush (Ericameria nauseosa var. nauseosa)
• Winterfat (Krascheninnikovia lanata)
• Broom snakeweed (Gutierrezia sarothrae)
• Fourwing Saltbush (Atriplex canescens)
• Snowberry (Symphoricarpos occidentalis)
The following mesic to wetland native shrubs are recommended for planting within Hickory Pond or along
Dry Creek, where the water table may be high and surface water may be present after rain events:
• Redosier dogwood (Cornus sericea)
• Coyote willow (Salix exigua)
• Waterbirch (Betula occidentalis)
• Wild black currant (Ribes americanum)
Plantings and/or plugs of wetland species is recommended in Hickory Pond or Dry Creek if inundation or
saturation precludes seeding. If necessary, these plantings should be concentrated in areas with high risk
of erosion to minimize the risk of soil loss. Planting should also be concentrated where favorable moisture
zones are likely to exist. Planting small plugs in the fall is not desirable due to the loss of plants to Canada
geese (Branta canadensis). Subsequent plantings are recommended after initial establishment and when
weeds are controlled (2-5 growing seasons after initial construction). These plantings can be concentrated
in areas needing additional erosion control protection and/or bare areas. Supplemental temporary irrigation
should be used to aid in establishing newly installed plant materials.
Step 4. Maintenance and Management
Maintenance and management activities should be implemented to ensure success of the ecological
restoration project. After seeding, the area shall be covered with crimped straw, jute mesh, or other
appropriate soil surface stabilization methods. Straw mulch should be certified weed-free hay or certified
weed-free straw with no seed heads. In the stormwater drainage area, natural fiber blankets are
recommended, as synthetic blankets can entangle reptiles and amphibians in aquatic habitats. Routine
inspections for erosion should be performed during the time between seeding and vegetation
establishment to assure no excessive erosion features form on the project area.
Restoration goals can be achieved without the use of supplemental water if planting plans correspond to
local climatic patterns for native seeding, late fall or early spring. However, temporary supplemental
irrigation is planned within the upland restoration areas in the NHBZ to ensure more reliable
establishment in a variety of potential climatic conditions. Temporary supplemental irrigation will be used
in a manner to provide no more than 150% of normal precipitation for the area (inclusive of
precipitation) and will be removed at least one growing season prior to measurement of the success
criteria presented in Section 4.4. Monthly normal precipitation and maximum total applied water values
for the growing season are presented on the following table:
Month Normal Precipitation
(inches)
Maximum Applied Water
(inches) *
April 2.06 3.09
May 2.43 3.64
June 2.17 3.25
July 1.71 2.56
August 1.60 2.40
September 1.33 1.99
*These values are inclusive of precipitation.
The Weed Management Plan (Cedar Creek 2024) provided for the site will be implemented to ensure that
weeds are properly managed before, during, and after seeding activities. Overall, the contractor shall
monitor seeded area for erosion control, germination, and reseeding as needed to establish cover.
4.0 ANNUAL MONITORING PLAN
The applicant will be responsible for ensuring execution of the monitoring and reporting protocol
described below. Annual monitoring will continue for at least three years following restoration of the
NHBZ.
4.1 Schedule
The NHBZ will be inspected at least three times per year and quantitative survey will occur once per year
on the following schedule:
1. In the spring (April), middle of summer (June), and fall (September) a qualified ecologist will
traverse the entirety of the site to assess overall performance of restoration, including noxious and
invasive weed populations prior to implementation of management strategies. This effort will result
in optimized and targeted weed control efforts and provide sufficient time to manage weeds prior
to seed production.
2. At the peak of growing season, a qualified ecologist will implement the quantitative procedure
described in section 4.2 to measure ground cover within the NHBZ. The ecologist will also traverse
the entirety of the site to identify potential problems or issues with restoration. During these
traverses, the observer will take note of areas of poor seedling emergence, indicators of soil fertility
problems, noxious weeds or invasive plant infestation , expectations for noxious weed
seeding/flowering, excessive erosion, and any other similar revegetation / restoration related issues
(if observed).
The consultant shall notify the City of Fort Collins Environmental Planning prior to each inspection. After
each inspection of the NHBZ, the consultant should email a brief narrative summarizing the findings of
the site visit and corresponding action items to City of Fort Collins Environmental Planning, the developer,
and the landscaping contractor.
A brief report containing survey findings and recommendations will be provided to the City by October
31st of each year. This will give the City of Fort Collins Environmental Planning and the applicant ample
time to discuss and implement adaptive management to address any underperforming areas prior to
when on-the-ground treatment implementation would be needed, if determined necessary.
4.2 Permanent Photo-points
Eight permanent photo-points (marked with GPS coordinates) on the site will be established to visually
catalog vegetation progress, including, 4 along the Dry Creek riparian corridor, 2 within Hickory Pond, and
2 within surrounding upland grassland area. Photo-points should be determined in the field at a location
representative of the NHBZ area, each location marked with GPS coordinates, and each designated with a
number which will remain consistent throughout the 3-year monitoring period. Each photo-point should be
documented during the summer evaluation at the pe ak of the growing season, for each of the annual
monitoring efforts that will follow restoration. At each point, four photos will be collected, one each in a
cardinal compass direction (N-E-S-W), using a photo board that is visible in each frame to indicat e the
photo-point number.
4.3 Sampling Methodology
Cover sampling will be conducted at a minimum of 15 sample points in the reclaimed areas of the NHBZ to
assess progress towards standards. Ground cover at each sampling site is determined utilizing the point-
intercept method (Bonham 1989). Implementation of the technique for the sampling effort occurs as
follows: First, a transect of 10 meters length is extended from the starting point of each sample site toward
the direction of the next site to be sampled. Then, at each one -meter interval along the transect, a laser
point bar is situated vertically above the ground surface, and a set of 10 readings re corded as to hits on
vegetation (by species), litter, rock (greater than 2mm), or bare soil. Hits are determined at each meter
interval by activating a battery of 10 specialized lasers situated along the bar at 10 -centimeter intervals
and recording the variable intercepted by each of the narrow (0.02 inch) focused beams (see Figure 1). In
this manner, a total of 100 intercepts per transect are recorded resulting in 1 percent cover per intercept.
4.4 Success Criteria
Total vegetative ground cover and diversity standards will be determined using a reference area approach,
where the reference areas are representative of the target vegetative community and are selected by the
City Environmental Planner. The total vegetative ground cover of the applicable reference area(s) will be
measured by the City annually at the end of the growing season (late summer to early fall) to the point of
demonstrating sample adequacy in order to provide an accurate level of vegetative cover r eflective of local
climatic conditions, as described in detail in the link below. The reference areas should account for the
difference between areas of restoration and preservation.
https://www.fcgov.com/developmentreview/environmentalplanningresources
The areas of the Development that are planned to be NHBZ mitigation areas shall be inspected jointly by
the Developer and the Environmental Planner at specified intervals for a minimum of three (3) growing
seasons or until determined by the Planner to be well established in accordance with the coverage
specifications of this paragraph, whichever occurs first. The NHBZ success criteria are as follows:
(1) The total vegetative ground cover contributed by all desirable plant species (excepting mature
trees) is equal to or greater than the desirable vegetative cover of the applicable reference area(s)
from that calendar year,
(2) No more than five percent (5%) of the species noted on the site may be weedy or noxious species
as defined by City Code Section §20-41 and Colorado Department of Agriculture’s Noxious Weed List
as defined by the Colorado Noxious Weed Act §§35-5.5,
(3) The development site shall display no evidence of detrimental erosion due to rills, gullies or
excessive bare spots of ground,
(4) Survival rate of all planted shrubs and trees is equal to or greater than eighty percent (80%), and
(5) Any diversity standards applied according to the City Environmental Planner’s discretion. Diversity
standards should be reflective of the reference area or target habitat conditions provided by the City.
by the City Environmental Planning Department and Utility Services Department.
The City Environmental Planning Department has the authority to deem revegetation established in lieu of
meeting success criteria, as well as withhold approval despite meeting success criteria, if they so choose .
If final stabilization is not achieved to the satisfaction of the agency, the developer and/or landscape
contractor shall be responsible for additional corrective measures to satisfy final vegetative requirements
for closeout.
5.0 LITERATURE CITED AND DATA SOURCES
Cedar Creek Associates, Inc. 2024. Mason Street Development Weed Management Plan. January 2024.
_____. 2023. 1311 North College Ecological Characterization Study. February 2023.
City of Fort Collins. 2021. Land Use Code. March 5, 2021.
_____. 2018. Stormwater Criteria Manual. December 2018.
_____. 2009. Landscape Design Standards and Guidelines for Stormwater and Detention Facilities.
November 2009.
U.S. Army Corps of Engineers. 2020. National Wetland Plant List – Great Plains Region.
http://rsgisias.crrel.usace.army.mil/NWPL/index.html
United States Forest Service (USFS). 1984. Brown, D.; Hallman, R.G. Reclaiming Disturbed Lands.