HomeMy WebLinkAboutMASON STREET INFRASTRUCTURE PROJECT - FDP230016 - SUBMITTAL DOCUMENTS - ROUND 3 - SUPPORTING DOCUMENTATION (7)
Technical Memo
PO Box 272150
Fort Collins, CO 80527
Date: December 19, 2023
To: City of Fort Collins, Planning, Development, and Transportation, Environmental Department
From: Cedar Creek Associates, Inc.
Subject: 1311 North College Natural Habitat Buffer Zone Preliminary Proposed Seed Mixes
Introduction
This document presents preliminary proposed seed mixes for the Natural Habitat Buffer Zone
(NHBZ) (per City of Fort Collins Land Use Code 3.4.1) located at the Mason Street Development
Project (project). Project design, particularly of the regional detention pond, is not finalized, and a
complete restoration plan will be completed once more design details and site layout are final. The
project 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.
Existing Conditions
An Ecological Characterization Survey (per City of Fort Collins) was completed in February 2023,
following a field review in September 2022. The project mostly includes upland grasslands,
dominated by non-native species, including smooth brome (Bromus inermis), orchard grass
(Dactylis glomerata), alfalfa (Medicago sative), and prickly lettuce (Lactuca serriola). Dry Creek
exists within the project area but exhibits no bed and bank or wetland characteristic. Forested
riparian exists along Dry Creek and is also dominated by non-native species, including crack willow
(Salix fragilis), Siberian elm (Ulmus pumila) and white popular (Populus alba) while smooth brome
is dominant in the herbaceous layer. In general, native vegetation is limited throughout the project
area, with a few small patches of Western wheatgrass (Pascopyrum smithii) in the upland pastures
and horse tail (Equisetum sp.) and showy milkweed (Asclepias speciosa) in Dry Creek. Native woody
species are limited and include rose (Rosa woodsii), wild licorice (Glycyrrhiza lepidota), narrowleaf
willow (Salix exigua), and a linear stand cottonwood (Populus deltoides) along the southeastern
boundary of the project area.
Although Dry Creek does meet the definition of stream or wetland, this resource is considered a
Natural Habitat Feature per the City of Fort Collins Land Use Code 3.4.1 and therefore requires a
100-foot buffer zone (NHBZ).
Proposed Impacts
The project plans currently propose impacts to a total of 76,484 square feet (approximately 1.76
acres) of NHBZ, including proposed piping of Dry Creek, to facilitate the construction of required
infrastructure.
Preliminary Proposed Seed Mixes
To mitigate the proposed 76,484 square feet of NHBZ impacts, an approximate 77,013 square foot
(approximately 1.77 acres) NHBZ Mitigation Area has been established. It is anticipated that a
regional detention basin will be installed within the NHBZ Mitigation Area. Therefore, the proposed
seed mix in Table 1 below focuses on mesic species that will be conducive to successful growth
given the edaphic conditions within this environment. Table 2 presents an upland seed mix that is
anticipated to surround the detention basin. This mix is focused on increasing the upland grassland
habitat value and providing additional diversity, while mitigating for any milkweed species that may
be eliminated during construction.
Note that modifications and improvements to these seed mixes are expected, as more design
information becomes available.
Note that a future restoration plan will be completed, which will include proposed existing invasive
species treatment, site and soil assessment and preparation, seeding techniques, mulching, time
frames, irrigation, and other details.