HomeMy WebLinkAboutRIDGEWOOD HILLS - FDP230019 - SUBMITTAL DOCUMENTS - ROUND 3 - Supporting Documentation (4)
April 1, 2024
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP 200024
SW Corner of Triangle Dr and College Ave
Fort Collins, CO 80525
Prepared for:
Russell + Mills Studios
506 S College Ave, Unit A
Fort Collins, CO
Pinyon Project No.:
124128707
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page i
Table of Contents
1. Overview ............................................................................................................................................................................ 1
1.1 Mitigation Requirements ..................................................................................................................................... 2
1.1.1 Wetland Mitigation Requirements .................................................................................................... 2
1.1.2 Wildlife Mitigation Requirements ..................................................................................................... 3
2. Adaptive Management Plan ............................................................................................................................................ 4
2.1 Monitoring .............................................................................................................................................................. 4
2.1.1 Monitoring Goals .................................................................................................................................. 4
2.1.2 Monitoring Criteria & Methods ......................................................................................................... 5
2.1.3 Reporting ................................................................................................................................................ 7
2.1.4 Communication ..................................................................................................................................... 7
2.2 Management Recommendations and Strategies ............................................................................................ 7
2.2.1 Vegetation .............................................................................................................................................. 8
2.2.2 Soil Recommendations ........................................................................................................................ 9
2.2.3 Hydrology ............................................................................................................................................. 12
2.2.4 Weeds ................................................................................................................................................... 15
2.2.5 Wildlife .................................................................................................................................................. 16
3. References ....................................................................................................................................................................... 18
Tables
Table 2-1. Vegetative Performance Standards and Monitoring ................................................................................... 5
Table 2-2. Wetland Performance Standards and Monitoring ...................................................................................... 6
Figures
Figure 1 Project Location
Figure 2 Existing Wetlands
Figure 3 Proposed Wetland and Natural Habitat Buffer Zones (NHBZs) Improvements
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 1
1. Overview
The intent of the Ridgewood Hills Fifth Filing Adaptive Management Plan (AMP) is to outline specific strategies,
approaches, and protocols related to pre-construction, construction, and post-construction care of wetlands
and Natural Habitat Buffer Zones (NHBZs) on site. Russell + Mills Studios (RMS) has finalized Wetland
Mitigation Plans as of April 2, 2024 that are a part of their Final Development Plan submission to the City of
Fort Collins (COFC) for the Ridgewood Hills Fifth Filing. The Wetland Mitigation Plans detail the mitigation
actions proposed to offset impacts to wetlands that are anticipated to result from construction of Ridgewood
Hills Fifth Filing as required by COFC. Once constructed, the wetland mitigation areas will provide 1.92 acres
of wetlands and 1.82 acres of NHBZ.
The proposed project is located at the southwest corner of College Avenue and Triangle Drive. It is bounded
on the west side by the existing Ridgewood Hills neighborhood and undeveloped open space to the south, with
the roads bounding it on the north and east sides (Figure 1). The project site is approximately 35 acres and is
undeveloped with no existing structures on site. The North Louden Ditch generally meanders north to south
through the site before leaving the site in the far southwest corner.
The design intent of the Ridgewood Hills Fifth Filing is to provide additional housing within this area of Fort
Collins and is located within the Medium Density Mixed-Use (MMN) zone district. While the plan is dictated
by the applicable zoning requirements regarding density and other requirements - there has been careful
planning and design to create a suitable transition towards the existing Low Density Mixed-Use (LMN) areas
to the north and west of the site. The most dense product (multi-family apartments) is located along College
Avenue - furthest away from the existing single-family area. The other product types (duplex and townhome
units) are planned to be adjacent to the existing single-family area.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 2
1.1 Mitigation Requirements
Below describes the mitigation requirements of COFC for Ridgewood Hills Fifth Filing for wetland mitigation
and wildlife mitigation.
1.1.1 Wetland Mitigation Requirements
Ridgewood Hills Fifth Filing includes ten wetland areas. See Wetland + Buffer Impacts Exhibit, dated March 29,
2024 for details of existing wetlands on the project site. “The [United States Army Core of Engineers (USACE)]
determined that all of the wetlands on the site are non-jurisdictional. Wetland mitigation is being proposed on
the site to meet City of Fort Collins requirements not [USACE] requirements.” (WCI, 2020).
Project construction is proposed to fill a total of 0.34 acres of non-jurisdictional wetlands on site. This will
include impacting the northeast corner wetland, the wetland on the north side of the property and various
parts of the ditch, with the far south side wetland to remain. The existing wetlands are associated with the
North Louden Ditch, described above. Per COFC regulations impacts to wetlands must be mitigated, regardless
of jurisdictional status. For this project the COFC requires mitigation of impacts to wetlands at a one to two
ratio. Proposed creation of wetlands for the project site is 1.92 acres (not including wetlands created in
detention ponds).
Per the “Wetland Monitoring Plan – Ridgewood Hills Project” (WCI, 2020) the following are included in the
wetland mitigation requirements:
Ø “At least 1 acre of new wetland area will be created on the site (adjacent to Wetland [Area 10]) to mitigate
for the 0.49 acres of wetland loss. In addition 0.71 acres adjacent to Wetland [Area 10] will be enhanced with
plantings of riparian vegetation (shrubs and trees) to create structural diversity and to enhance wetland
functions for wildlife. Note: additional wetlands (beyond the 1 acre) will be created in detention areas. Weed
control (Canada thistle: Cirsium arvense) will be completed on and adjacent to Wetland [Area10]. Wetland
functions of mitigated wetlands will be equal to wetland functions of lost wetlands.
Ø Wetland Mitigation will determined to be successful when:
o At least 80% (determined by ocular estimate of herbaceous and shrub foliar cover) of the mitigation
site(s) is vegetated, at least 50% of the total number of dominant species present will consist of species
rated as facultative or wetter.
o Riparian shrub and tree survival will be at least 80%.
o Those species shown on the Colorado Noxious Weed Inventory list-A shall be 100% eradicated. Those
species shown on list-B shall be no more than 10% or less of the total cover in the mitigation area.
Weed control will follow the Weed Management Plan prepared for the project.
o Wetland hydrology and wetland soils are present (as defined by [USACE] delineation standards).
Ø Annual Mitigation Monitoring Reports will be submitted to the City of Fort Collins.”
See Wetland + Buffer Impacts Exhibit, dated March 29, 2024 for a detailed breakdown of proposed wetland
and NHBZs improvements.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 3
1.1.2 Wildlife Mitigation Requirements
The Migratory Bird Treaty Act (MBTA) protects birds and their active nests (except for Rock Doves [Columbia
livia], European Starlings [Sturnus vulgaris], and some other non-native birds). In Colorado, most nesting and
rearing activities occur between April 1 and August 31; however, raptors may nest as early as December. These
timeframes are guidelines and nesting birds are protected under the MBTA year-round. To comply with the
MBTA, the following actions should be taken:
Ø If construction is to occur between December and August, pre-construction surveys are
recommended to determine whether nesting birds are present with the potential to be impacted by
the project. If nesting raptors are noted within 0.5 mile of the study area, then the recommendations
outlined in the Colorado Parks and Wildlife (CPW) Recommended Buffer Zones and Seasonal Restrictions
for Colorado Raptors should be followed (CPW, 2020). Bald and Golden Eagles are also protected under
the Bald and Golden Eagle Protection Act (BGEPA); if eagles develop nests in the area, additional
coordination with the U.S. Fish and Wildlife Service (USFWS) may be required.
Ø If feasible, ground-disturbance activities should occur prior to April or after August to avoid impacts
to ground-nesting birds. If this timeframe is not feasible, “clear and grub” nesting surveys are
recommended within planned work areas within ten days prior to vegetation clearing. If active nests
are noted, they should be flagged for avoidance until the young have left the nest. Inactive (unoccupied)
nests may be removed anytime.
Additionally, per comments received from the COFC (COFC, 2021) the following is required for the existing
American Kestrel nest found on site:
“Hazard Tree #55 which houses the American Kestrel nest is to be relocated on the ground via controlled
removal methods and retained at its current location. Ensure the cavity is facing SE and perched (if possible)
like a tripod using large branches to slightly prop the trunk. Tree to be controllably removed in final stages of
construction phasing, with nest boxes installed at the beginning to allow the Kestrel an opportunity to relocate
if desired. Please coordinate with City Environmental Planner and City Forestry before placing the tree. Ensure
the tree is not altered during the nesting season (Feb 1 through July 31). Tree work to be done by a City of
Fort Collins Licensed Arborist. A list of licensed companies can be found on the Forestry website:
fcgov.com/forestry.
Developer (or general contractor) shall provide selected arborist contractor information with City Forestry and
Environmental Planning prior to on-site coordination. Field coordination meeting to occur prior to tree placement
to ensure proper practices are used to protect Kestrel nest and cavity.”
As requested by COFC, the above notes are also reflected in the plan set for Ridgewood Hills Fifth Filing.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 4
2. Adaptive Management Plan
The intent of the AMP is to outline specific strategies, approaches, and protocols related to pre-construction,
construction, and post-construction care of existing and mitigated wetlands and NHBZs on site. Monitoring
described in this AMP will inform management and maintenance activities necessary to reach the project’s
mitigation goals.
Following construction, the Developer will monitor and maintain Ridgewood Hills Fifth Filing wetlands and
NHBZs for a minimum of three growing seasons or until determined by the COFC that success criteria has
been achieved. Two Monitoring Memorandums and one Annual Report per year will be submitted to COFC
and will be the key method for identifying and communicating maintenance needs. Maintenance items will also
be noted incidentally during other activities taking place at the site, such as required monthly stormwater
inspections. This and other activities will require frequent site visits following project construction, and
personnel will be trained to recognize conditions that could compromise the wetland mitigation area and
NHBZs.
2.1 Monitoring
Monitoring is a tool to help establish baseline conditions, trends towards success, and the early identification
of obstacles to meeting mitigation goals. By tracking and adapting management strategies to site conditions
during the project, the Developer can better protect existing wetlands and NHBZs, as well as support and
establish newly created mitigation areas and NHBZs so they can meet performance standards.
Monitoring of Ridgewood Hills Fifth Filing will occur during the following timeframes:
• Pre-construction: establish baseline conditions of existing wetland and NHBZs; monitoring and protection
of existing wetlands and NHBZs to remain.
• Construction: monitoring and protection of existing wetlands and NHBZs to remain; creation of new
wetlands and NHBZs; monitoring and protection of new wetlands and NHBZs.
• Post-construction: monitoring and protection of both existing and new wetlands and NHBZs for a
minimum of three growing seasons post-construction, until performance standards have been met and
monitoring requirements have been fulfilled.
2.1.1 Monitoring Goals
The following are monitoring goals for Ridgewood Hills Fifth Filing:
• Maintain and protect existing wetlands and NHBZs during and after construction.
• Create and establish new wetlands and NHBZs during pre-construction, maintain and protect the site
during construction and post-construction.
• Minimize disturbance to migratory birds, state or federally listed species, and the American Kestrel
documented on-site during nesting season. The wetlands and HNBZs will also provide nesting habitat for
the American Kestrel and other migratory birds.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 5
2.1.2 Monitoring Criteria & Methods
Included in this section are performance standards per the Development Agreement, monitoring methods, and
monitoring frequency for vegetation, wetlands, and wildlife.
2.1.2.1 Vegetation Performance Standards & Monitoring Methods
Per the Development Agreement for Ridgewood Hills Fifth Filing, the following is required by COFC for
establishment coverage:
Table 2-1. Vegetative Performance Standards and Monitoring
Performance Standards Monitoring Methods Monitoring Frequency
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.
No more than five 5% of the
species noted on the site may be
invasive and noxious weed
species
Line-intercept procedure
(Herrick et. al., 2021) Once per year
Vegetative cover will be assessed
at permanent sampling points in
order to evaluate the progress of
revegetation
A minimum of twice per year
with additional visits as needed
Invasive and noxious weed
species assessment (categorical
observation-based protocol)
A minimum of twice per year
with additional visits as needed
The development site shall
display no evidence of
detrimental erosion due to rills,
gullies or excessive bare spots of
ground
General site condition
assessment (categorical
observation-based protocol)
A minimum of twice per year
with additional visits as needed
The survival rate of all planted
shrubs and trees is equal to or
greater than eighty percent (80%).
Plant survivorship counts
(objective assessment)
A minimum of twice per year
with additional visits as needed
General monitoring requirements from COFC for this AMP include the following:
• Vegetative cover assessments are required to be performed during the growing season.
o Cover should ideally be measured during the peak of the growing season (i.e., mid-summer to
early fall).
In addition to the above, the Development Agreement specifies the following:
Total vegetative ground cover and diversity standards (if applicable) will be determined using a reference area
approach, where the reference areas are representative of the target vegetative community(ies) and are
selected by the City Environmental Planner. The total vegetative ground cover of the applicable reference
area(s) will be measured annually at the end of the growing season (late summer to early fall) to the point of
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 6
demonstrating sample adequacy in order to provide an accurate level of vegetative cover reflective of local
climatic conditions. Acceptable desirable total vegetative cover of the NHBZ cannot be less than 40%.
Determination of required coverage of the NHBZ will be measured using a line point intercept method with a
number of transects approved by the Environmental Planner across the target habitat type(s) present,
distributed either randomly or on a grid-based pattern, to gain an adequate representation of the seeded areas.
2.1.2.2 Performance Standards for Wetlands
Performance standards are included to assess overall wetland functioning for the existing and proposed
wetlands, as well as to assess specific wetland indicators of vegetation, soils, and hydrology as follows:
Table 2-2. Wetland Performance Standards and Monitoring
Performance Standards Monitoring Methods Monitoring Frequency
FACWet Assessment Score of
0.7 or greater than existing
FACWet assessment conditions
(“functioning” condition)
FACWet assessment Once per year
Vegetation cover success will be
defined depending on the results
of COFC applicable reference
area(s).
Line-intercept procedure
(Herrick et. al., 2021)
Once per year
The mitigation area will have no
more than 5% invasive and
noxious weed species in all
stratigraphic levels (forbs, shrubs,
and trees).
Line-intercept procedure
(Herrick et. al., 2021) Once per year
Invasive and noxious weed
species assessment (categorical
observation-based protocol)
A minimum of twice per year
with additional visits as needed
Soils: one or more hydric soil
indicators present in sampled
wetland soil pits.
Hydric soil indicators will be
assessed following the Regional
Supplement to the Corps of
Engineers Wetland Delineation
Manual: Great Plains Region
(Version 2.0) (USACE, 2010).
Once per year
Hydrology: one or more primary
hydrology indicators or two or
more secondary indicators are
present in sampled wetland soil
pits.
Hydrology indicators will be
assessed following the Regional
Supplement to the Corps of
Engineers Wetland Delineation
Manual: Great Plains Region
(Version 2.0) (USACE, 2010).
Once per year
General monitoring requirements from COFC for this AMP include the following:
• Water level monitoring should occur over the course of the growing season (April 1 to October 31).
2.1.2.3 Performance Standards for Wildlife Mitigation
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 7
If MBTA is triggered due to the presence of migratory birds and monitoring is required, appropriate timing of
monitoring is dependent on the species. The Developer will consult with appropriate CPW guidance and COFC
Environmental Planner.
2.1.3 Reporting
The Developer will provide two Maintenance Memorandums and one Annual Report per growing season.
Maintenance Memorandums are intended to occur earlier in the growing season and provide status updates,
with the Annual Report summarizing the entire growing season.
Maintenance Memorandum: will include high level updates showing observations and data from monitoring,
inspection, and management efforts throughout the growing season.
Annual Report: Data to be summarized as part of the annual monitoring reports shall contain, at a minimum,
the following:
• Monitoring methods
• Performance standards
• Annual monitoring data
• Quantitative comparison of current year results with past years’ results
• Assessment of observed trends or trajectory of measure parameters
• Site photos, including permanent photo monitoring points
• A discussion of the success or failure of achieving performance standards
• Recommendations for remedial actions, if necessary
2.1.4 Communication
Compliance with the AMP will be the responsibility of the AMP Manager, Kirk Johnston of Goodwin Knight.
The AMP Manager will be responsible for coordinating with consultants and/or contractors throughout pre-
construction, construction, and post-construction actions to implement the AMP. This includes on-going
coordination to communicate deficiencies and implement appropriate management strategies in a timely
manner. Monitoring for the AMP will be completed by a qualified biologist and will meet standards per the
COFC and the Developer.
2.2 Management Recommendations and Strategies
The following are recommendations that cover vegetation, soil, hydrology, weeds, and wildlife.
Recommendations cover pre-construction, construction, and the post-construction establishment phases. It is
recommended that a long-term management plan be developed once establishment and success criteria are
met to be utilized by the property owners.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 8
The following recommendations for revegetation, soil preparation, soil amendments, erosion control, and weed
management should be incorporated into the plan notes or project specifications.
2.2.1 Vegetation
2.2.1.1 Indicators
• Species diversity: Monitor changes in species richness and evenness over time. Declines or increases can
indicate shifts in ecosystem health.
• Vegetation cover: Changes in vegetation cover can indicate alterations in land use, disturbance, or invasive
and noxious weed species encroachment.
• Plant health: Monitor for signs of disease, pest infestation, or nutrient deficiencies in key plant species.
• Community Composition: Monitor shifts in plant community, such as if wetland vegetation is shifting into
upland species.
2.2.1.2 Pre-construction
• It is recommended that baseline conditions be recorded of existing wetlands and NHBZs. This should
include a functional assessment of wetlands to determine current wetland conditions on site. The objective
of the baseline conditions is to document existing vegetation and undesirable species. Vegetation that is
desirable and already successful on site can help to inform later recommendations, such as modifications
to proposed seed mixes.
• Weed management is recommended and critical for the establishment of seed, including active weed
management prior to seed placement. Refer to Section 2.2.4 Weeds for specific recommendations for
pre-construction.
• Soil conditions can affect seed success, whether due to nutrients or compaction. For specific soil
recommendations see Section 2.2.2 Soil Recommendations.
2.2.1.3 Construction
• Seeds require consistent moisture, but not overly wet soils, to germinate. Soils over saturated with water
may prevent oxygen (O2) exchange which in turn will limit or prevent germination. Exchange of gases is
essential for rapid and uniform germination. The following is recommended for seed establishment:
o Ensure seed has direct contact with soil when seeding the area.
o Water regularly (in the coolest part of the day) for two weeks or until seedlings emerge.
o Continue to water after seedlings emerge during the first growing season (generally once a
week, but depending on weather patterns).
o Follow up with mechanical weed control in this area as seedlings are developing, expect weed
seeds to germinate and flourish due to increased irrigation.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 9
• Weed control during establishment will also be critical. For more detailed information see Section 2.2.4
Weeds. The following is recommended:
o Do not apply herbicides during germination and establishment for the first growing season.
• The following is recommended for seeding with warm season grasses (June—October)
o When the soil is approximately 70° Fahrenheit (F) and above, warm season grasses will
germinate. Sow seeds in June through early October and follow germination and establishment
guidelines.
o It is feasible to sow warm season grasses in fall, however they will only germinate with warm
(soil) temperatures. Do not water after seeding in fall when sowing warm season grasses in
fall. Allow natural precipitation to germinate seeds or apply irrigation in June—October to
encourage germination.
• The following is recommended for seeding with cold season grasses and wildflowers (fall)
o Sow seeds in fall. Winter months will naturally provide moisture (in the form of snow and
early spring melt), cold stratification and seed scarification (via birds and animals). An excellent
time to sow seeds is around freeze-thaw events. The soil will often crack during these times.
Thereafter, precipitation events will allow seeds subject to freeze-thaw to fall into cracks,
covering them gently with soil and positioning them to receive additional precipitation
throughout the winter months and into spring, encouraging germination.
o Alternatively, irrigate fall seed species in spring (May) — follow germination and establishment
guidelines.
• Overseeding is recommended after seed germination as a spot treatment for any areas that have not been
established. Hand broadcasting is recommended for spot treatment to avoid disturbance to established
seeds. Hand-broadcasted areas should be harrowed and raked to cover the seed. Ongoing spot treatment
is recommended on an as needed basis.
2.2.1.4 Post-construction
• It is recommended to adapt seed mix based on results and reseed as needed to address areas of inadequate
establishment. Seed mix adaptation should be informed by existing baseline conditions previously
documented during pre-construction.
• It is recommended whenever possible to opt for mechanical weeding for a minimum of one growing season,
and two seasons when feasible to minimize impacts to seeding.
2.2.2 Soil Recommendations
Soil plays a large role both as a filtration device and a growing media. Soil significantly influences the system’s
performance and can impact key factors such as infiltration, water quality, planting strategy, costs, and long-
term maintenance. Soil is not static; sediment builds, nutrients deposit, and seasons change all impact soil’s
characteristics over time. Starting with a healthy and balanced soil composition can increase the longevity of
the system, reduce maintenance costs, and better support system functions in extreme environments.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 10
2.2.2.1 Indicators
• Plant health: yellowing or chlorosis of leaves, stunted growth, wilting or drooping foliage, leaf curling,
increased susceptibility to pests and diseases, browning or necrosis of leaf margins, and overall decline in
vigor and vitality.
• Soil compaction: reduced water infiltration rate, increased surface runoff, surface crusting, hard soil surface,
water pooling or ponding, reduced soil porosity, bare ground, or sparse vegetation.
• Soil erosion: Exposed roots, rill and gully formation, loss of topsoil, sediment deposits, surface crusting,
bare soil patches, slope failure, loss of soil structure, changes in soil color, and the presence of eroded
material.
• Hydric Soils: Refer to Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Great
Plains Region (Version 2.0) (USACE, 2010) for hydric soils indicators.
2.2.2.2 Pre-construction
• Soil Function
o Determine the desired roles of the soil media and whether you will be using existing topsoil,
amending existing topsoil, or using certified topsoil with a consistent composition.
• Soil Nutrient and Structure Testing
o It is recommended to test soil structure and composition, to assess features such as particle
sizes based on the U.S. Department of Agriculture (USDA) soil classification system:
§ Water Permeability, Maximum Media Water Retention, Total Pore Space, and
Particle Size Evaluation.
o Soil nutrient testing to include:
§ Complete: pH, soluble salts (EC), organic matter (OM), lime, cation exchange capacity
(CEC), % base saturation, nitrate nitrogen (NO3-N), phosphorus (P), potassium (K),
calcium (Ca), magnesium (Mg), sodium (Na), SO4-S (sulfate -sulfur), zinc (Zn), iron
(Fe), manganese (Mn), copper (Cu), and boron (B), sodium absorption ratio (SAR),
and soil texture
o It is recommended that a landscape architect, ecologist, biologist, or soil scientist analyze soil
testing results to provide recommendations for use and/or amendments.
• Hydric Soils Baseline Assessment for Existing Wetlands
o Assess for hydric soil indicators by following the Regional Supplement to the Corps of
Engineers Wetland Delineation Manual: Great Plains Region (Version 2.0) (USACE, 2010).
2.2.2.3 Construction
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 11
• Site Protection and Stabilization
o It is recommended that protection fencing, stormwater control best management practices
(BMPs), and erosion control BMPs be used to protect all areas that are to remain undisturbed,
including existing wetlands and NHBZs, to minimize soil impacts such as compaction, erosion,
and contamination.
• Proper topsoil stockpiling
o Wetland topsoil should be stockpiled separately. It is recommended to place wetland topsoil
within 24 hours from excavation. Wetland topsoil should not be stockpiled for more than six
months.
o Existing topsoil that is stockpiled should be treated with herbicide prior to placement reduce
weed seed bank. Wetland stockpiles shall not be treated with herbicide and should prioritize
hand pulling. Refer to section 2.2.4 Weeds for more information.
o All Stockpiles of topsoil which are scheduled to remain in place for 14 days or more shall
receive interim stabilization.
• Soil Nutrient Testing
o Soil nutrient testing is recommended during construction to help adapt soil amendment
recommendations as needed. Soil nutrient testing should apply to both imported and salvaged
soils.
o It is recommended that a landscape architect, ecologist, biologist, or soil scientist analyze soil
testing results to provide recommendations for use and/or amendments.
• Subgrade and Topsoil Preparation
o Proper subgrade and topsoil preparation and placement during construction to avoid
compacted soils.
o Subgrade is recommended to be ripped to a minimum depth of 14 inches. Subgrade depths
of penetration shall confirm that a minimum of 12 inches can be achieved without reaching
300 psi on the rod penetrometer pressure gage (approximately 30 pounds of pressure on the
T-handle).
o Topsoil is recommended to be placed with a minimum thickness of 6 inches and should only
be handled when it is dry enough to work without damaging soil structure. Placement methods
should not re-compact subgrade material. It is recommended to use low ground-contact
pressure equipment, excavators and/or backhoes to avoid recompaction.
o Any construction activities beyond topsoil and seeding activities that occur could potentially
cause compacted soils and should be tested for compaction and addressed as appropriate.
2.2.2.4 Post-construction
• Stabilization
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 12
o It is recommended that basic stormwater management and erosion control BMPs be followed
until vegetation is established and soil is stabilized.
o On-going stormwater management and erosion control BMPs are recommended to address
erosion and ground disturbances as needed caused by storm events, land use, etc.
• Compacted Soils
o Areas of compacted topsoil with bare, sparse, stunted, anemic, or weedy vegetation are
recommended to be scarified and decompacted to prepare the soil for seeding operations. A
soil penetrometer rod test is recommended to test soil compaction to help determine depth
of soil compaction. Below is a list of soil preparation recommendations to prepare topsoil for
decompaction:
§ Areas where soil compaction is greater than 6 inches in depth, rip soils to a minimum
depth of 12 inches by disking, ripping, plowing, and or rototilling in two directions
perpendicular to each other.
§ Till the top 6 inches of topsoil, leaving no clods over 3 inches in diameter.
§ Firm soil bed for seeding, so a footprint will imprint between a 1/4-inch to 1/3-inch
• Soil Nutrient Testing
o Soil nutrient testing is recommended during establishment to help monitor soil health and
adapt soil amendment recommendations as needed.
o It is recommended that a landscape architect, ecologist, biologist, or soil scientist analyze soil
testing results to provide recommendations for use and/or amendments.
• Soil Amendments
o Consider topical soil amendments that increase nutrient uptake and reduce plants’ water
needs to support vegetation during extreme climate conditions.
• Hydric Soils Assessment for Existing and Created Wetlands
o Assess for hydric soil indicators by following the Regional Supplement to the Corps of
Engineers Wetland Delineation Manual: Great Plains Region (Version 2.0) (USACE, 2010).
o Adaptive management strategies for wetlands must recognize the inherent limitations in
controlling soil development processes. Hydric soil indicators may take several years to
develop in created wetlands. It is recommended to prioritize vegetation indicators discussed
in 2.2.1. Determine if vegetation is trending towards successful wetland establishment in the
first three to five years post construction.
2.2.3 Hydrology
2.2.3.1 Indicators
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 13
• Hydrological changes: change in streamflow patterns, groundwater levels, flooding event frequency, or
shifts in peak flow timing.
• Vegetation composition: Changes in the composition of wetland vegetation can indicate shifts hydrology
regimes.
• Hydrology indicators: Refer to Corps of Engineers Wetland Delineation Manual: Great Plains Region
(Version 2.0) (USACE, 2010) for hydrology indicators.
2.2.3.2 Pre-construction
• Baseline Groundwater Monitoring
o It is recommended to collect pre-construction groundwater data at existing and proposed
wetland locations. Groundwater data should capture water levels, seasonal fluctuations, and
interactions with surface water sources. This data is critical to understand fluctuations during
and after construction, as well as potential changes in artificial irrigation sources.
o Documentation and recognition of preconstruction drainage flows and patterns that support
wetlands should be considered and incorporated into site design.
• Irrigation Sources Considerations
o The North Louden Ditch that runs through the site in its current configuration could be a
source of water for the existing wetlands. It is important to note the potential to water supply
changes via the ditch could impact groundwater supply to wetlands and is inherently out of
the Developer’s control.
• Wetland Hydrology Baseline Assessment for Existing Wetlands
o Assess for wetland hydrology indicators by following the Regional Supplement to the Corps
of Engineers Wetland Delineation Manual: Great Plains Region (Version 2.0) (USACE, 2015).
2.2.3.3 Construction
• Site Protection and Stabilization
o When possible, it is recommended to maintain site drainage patterns that support the existing
wetlands.
o It is recommended that basic stormwater management and erosion control BMPs be followed
during construction.
• Groundwater Monitoring
o It is recommended to continue groundwater monitoring at existing and proposed wetland
locations. Groundwater data should capture water levels, seasonal fluctuations, and
interactions with surface water sources. This data is critical to understand fluctuations during
construction, as well as potential changes in artificial irrigation sources.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 14
• Irrigation Source Considerations
o Irrigation: When using temporary and/or permanent irrigation for vegetation and/or wetland
establishment during construction, optimize irrigation practices to minimize water wastage
and maximize efficiency. Adjust irrigation schedules, water delivery methods, and application
rates based on post-construction soil moisture data and plant water requirements.
o Louden Ditch: It is important to note the potential water supply changes via the ditch could
impact groundwater supply to wetlands and is inherently out of the Developer’s control.
2.2.3.4 Post-construction
• Site Protection and Stabilization
o It is recommended that basic stormwater management and erosion control BMPs be followed
until vegetation is established and soil is stabilized.
o On-going stormwater management and erosion control BMPs are recommended to address
erosion and ground disturbances as needed caused by storm events.
• Groundwater monitoring
o It is recommended to continue groundwater monitoring at existing and propose wetland
locations. Groundwater data should capture water levels, seasonal fluctuations, and
interactions with surface water sources. This data is critical to understand fluctuations during
construction, as well as potential changes in artificial irrigation sources.
• Irrigation Source Considerations
o Irrigation: When using temporary and/or permanent irrigation for vegetation and/or wetland
establishment post-construction, optimize irrigation practices to minimize water wastage and
maximize efficiency. Adjust irrigation schedules, water delivery methods, and application rates
based on post-construction soil moisture data and plant water requirements.
o Louden Ditch: It is important to note the potential water supply changes via the ditch could
potentially impact groundwater supply to wetlands and is inherently out of the Developer’s
control.
• Wetland Hydrology Assessment for Existing and Created Wetlands
o Assess wetland hydrology indicators by following the Regional Supplement to the Corps of
Engineers Wetland Delineation Manual: Great Plains Region (Version 2.0) (USACE, 2010).
o Adaptive management strategies for wetlands must recognize the inherent limitations in
controlling groundwater dynamics. Hydrology indicators may take several years to develop in
created wetlands. It is recommended to prioritize vegetation indicators discussed in 2.2.1.
Determine if vegetation is trending towards successful wetland establishment in the first three
to five years post construction.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 15
2.2.4 Weeds
2.2.4.1 Indicators
• Weed presence and abundance: Look for the presence and abundance of invasive and noxious weed
species, particularly in wetlands and NHBZs.
• Weed distribution: Track changes in the spatial distribution of weed populations to identify areas of
infestation and prioritize management efforts.
• Weed impacts on native species: Assess the impacts of invasive and noxious weed species on native
vegetation and ecosystem processes.
• Weed management effectiveness: Evaluate the effectiveness of weed control measures implemented as
part of the management plan.
2.2.4.2 Pre-construction
• It is recommended to conduct a site visit to assess existing conditions within and adjacent to the site to
identify and survey invasive and noxious weed species and annual weeds that may impact the site.
• It is recommended to treat existing topsoil, if it is going to be utilized on site, to remove weeds from the
existing seed bank that could impact seed establishment.
• After conducting a site visit to assess existing conditions, it is recommended that pre-construction weed
management be identified based on onsite conditions and should be species specific which may have varied
appropriate treatments. Species such as Kochia (Bassia scoparia) take a minimum of two to three years of
consistent management to succeed and diminish the seed bank. Pre-construction management allows for
a larger variety of control methods.
• It is recommended to use a temporary seed mix to overseed with during preconstruction weed
management.
• Prior to tilling and soil preparation, site should be cleared and grubbed. This removes previous year’s weed
above and below ground biomass (Mechanical Control). See section 1.1.2 about required MBTA regulations
during clearing and grubbing.
• It is recommended to broadcast herbicide treatment prior to seeding application. Broadcasted herbicide
treatment must be completed at a minimum of 16 weeks prior to seeding. All herbicides must be applied
by a licensed Certified Herbicide Operator. (Herbicide Treatment)
2.2.4.3 Construction
• At a minimum, it is recommended that noxious weed species are managed per Colorado Department of
Agriculture (CDA) requirements. Additional considerations should focus on invasive and noxious weed
species that may overtake and out-compete desired species.
• After seeding any area, it is recommended that mowing should be delayed until native grasses are
established and have undergone a full growing season. Pulling or hoeing (Mechanical Control) during the
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 16
early growth stages of undesirable species and continuing this management throughout the season can be
effective at controlling undesirable species in all seeded areas. It is important to remove and dispose of
plant material to prevent the spreading of weeds after mechanical removal.
• Spot treatment application of herbicides (Herbicide Treatment) may be used in seeded areas. All herbicides
must be applied by a licensed Certified Herbicide Operator.
2.2.4.4 Post-construction
• Refer to the CDA fact sheets for species dependent recommendations based on installation timeline, life
cycle, weed species, noxious weed herbicide use, and mechanical removal.
• It is recommended to educate maintenance to accurately identify weed species and apply appropriate
control methods.
• It is recommended to continue weed control for multiple seasons after construction.
• It is recommended to closely observe non-irrigated areas, as they are more likely to have weed invasion
and establishment than irrigated areas due to native plants needing more water than weeds to germinate,
establish, and be dominant (out compete weeds).
• During establishment, recommend mechanical removal of weeds on a minimum monthly basis (weekly is
preferred) throughout growing season (May — October).
• At a minimum, it is recommended that noxious weed species are managed per CDA requirements.
Additional considerations should focus on weed species that may overtake and out-compete desired
species.
2.2.5 Wildlife
2.2.5.1 General
• Vegetation removal is recommended to be timed to avoid the migratory bird breeding season which begins
on April 1 and runs to August 31 and earlier for some raptors All areas scheduled for vegetation removal
between April 1 and August 31 are recommended to be surveyed for active migratory bird nests seven
days before ground disturbance within the project limits by a qualified biologist.
• The Developer is required to avoid the area of an active migratory bird nests by the distance recommended
by CPW’s Recommended Buffer Zones and Seasonal Restrictions for Colorado Raptors until all nests
within that area have become inactive (CPW, 2020).
• Per comments received from the COFC (COFC, 2021) the following is required for the existing American
kestrel nest found on site:
“Hazard Tree #55 which houses the American Kestrel nest is to be relocated on the ground via controlled
removal methods and retained at its current location. Ensure the cavity is facing SE and perched (if possible)
like a tripod using large branches to slightly prop the trunk. Tree to be controllably removed in final stages
of construction phasing, with nest boxes installed at the beginning to allow the Kestrel an opportunity to
relocate if desired. Please coordinate with City Environmental Planner and City Forestry before placing the
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 17
tree. Ensure the tree is not altered during the nesting season (Feb 1 through July 31). Tree work to be
done by a City of Fort Collins Licensed Arborist. A list of licensed companies can be found on the Forestry
website: fcgov.com/forestry.
The Developer (or general contractor) shall provide selected arborist contractor information with City
Forestry and Environmental Planning prior to on-site coordination. Field coordination meeting to occur
prior to tree placement to ensure proper practices are used to protect Kestrel nest and cavity.”
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525 Page 18
3. References
City of Fort Collins (COFC), “RE: Ridgewood Hills Fifth Filing, FDP200024, Round Number 3”, Summary of
Comments, John Beggs (Russell + Mills), May 21, 2021.
Colorado Parks and Wildlife (CPW), 2020. “Recommended Buffer Zones and Seasonal Restrictions for
Colorado Raptors.” Available at:
https://cpw.state.co.us/Documents/WildlifeSpecies/LivingWithWildlife/Raptor-Buffer-Guidelines.pdf.
Jeffery E. Herrick, et. al., “Monitoring Manual for Grassland, Shrubland, and Savanna Ecosystems”, 2nd ed.,
USDA-ARS Jornada Experimental Range, Las Cruces, New Mexico, June 2021.
United States Army Core of Engineers (USACE), 2008. Minimum Monitoring Requirements for Compensatory
Mitigation Projects Involving the Restoration, Establishment and/or Enhancement of Aquatic Resources,
Regulatory Guidance Letter. No 08-0. U.S. Army Corps of Engineers. October 10, 2008.
USACE, 2010. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Great Plains
Region (Version 2.0), ed. J. S. Wakeley, R. W. Lichvar, and C. V. Noble. ERDC/EL TR-10-1. Vicksburg, MS: U.S.
Army Engineer Research and Development Center.
Wildland Consultants, Inc. (WCI), 2020, “Wetland Monitoring Plan – Ridgewood Hills Project,” Wildland
Consultants, Inc., Berthoud, CO, August 2020.
WCI, 2021, “Wetland Monitoring Report, 2020 – Ridgewood Hills Project,” Wildland Consultants, Inc.,
Berthoud, CO, February 2021.
Ridgewood Hills Fifth Filing Adaptive Management Plan
Ridgewood Hills Fifth Filing, FDP200024
SW Corner of Triangle Rd and College Ave, Fort Collins, CO 80525
Figures