HomeMy WebLinkAbout011g Wetland Response to CommentsSundog Ecological Inc., Response to Naiad Comments
Document 011d – Wetland Delineation Report from 11/26/2023 letter
• Precipitation data updated and changes made on data forms
• Wetland setbacks are not applied to this irrigation ditch, the City has determined that
these wetlands are related to irrigation and under Sec 38.610.010 “The provisions contained in these regulations do not apply to wetlands created by a wholly manmade
water source used for irrigation purposes or stormwater control.” This is consistent with
previously approved projects located immediately upstream of the same irrigation ditch
(Gran Cielo Subdivision and Buffalo Run Site Plan). 011c-Wetland Regulation Analysis
• Section 38.610.090A. 1&5 Wetland buffer o Wetland setbacks are not applied to this irrigation ditch, the City has determined
that these wetlands are related to an irrigation facility and under Sec 38.610.010
“The provisions contained in these regulations do not apply to wetlands created by a wholly manmade water source used for irrigation purposes or stormwater
control.” This is consistent with previously approved projects located
immediately upstream of the same irrigation ditch (Gran Cielo Subdivision and Buffalo Run Site Plan).
o Gallatin Conservation District does not take jurisdiction over the waterway, as it
is an irrigation facility and does not convey groundwater when irrigation is off.
• Section 38.610.090A.6 Erosion and stormwater. The stormwater design report is included as item #009 in the application. There are no stormwater discharges to the
wetlands (all stormwater is captured and infiltrated in surface ponds or underground
chambers). There are no fill slopes steeper than 4H:1V designed across the entire development so no erosion into the wetlands is anticipated. Slopes adjacent to
wetlands will be seeded with erosion control matting directly after construction to
prevent erosion. A Stormwater Pollution Prevention Plan will be in place prior to any construction on site. Stormwater best management practices will be established and
maintained to prevent any impacts to wetlands. The City Stormwater Division and
Engineering Department have reviewed these plans and the applicant will continue to coordinate with these departments throughout the development.
• Section 610.090.A.13 Limit direct impact - The site was designed to minimize impacts to
the wetlands by protecting a majority of the existing wetland area within a City Park that
will be dedicated to the City. This irrigation ditch will not be altered with the exception of the new culvert crossings required to maintain the City’s transportation network. The
quantity and quality of water from this ditch will not be impacted by this project. There
are no improvements proposed within the wetlands so they are protected within City
property for perpetuity.
• Section 610.090.A.14 Local mitigation required
o Jurisdictional Determination was submitted to ACOE in 09/2023 and the
response is still pending; we have received an indication that it will be
Jurisdictional. A 404 permit application has been compiled and is pending
submission to ACOE.
Sheet 006 Existing Conditions
• The wetlands are included on Sheet 006 Existing Conditions. There is no applicable
watercourse setback. Sheet 009 NE Site Plan and 010 SE Site Plan
• The wetlands and the irrigation ditch linework are included on Sheet 009 and Sheet 010.
There is no applicable watercourse setback. Communication 011a email to Brian Heaston regarding watercourse buffer
• Yes, there is no applicable watercourse setback. Communication 011b Wetland Checklist
• Please see the Wetland Impact Exhibit (item #011f in the documents folder) for the summary of wetland impacts. An additional table is attached to this response below.
• “Assessment to changes in hydroperiod”? A perforated culvert will be used at road crossings to ensure hydrologic connectivity downstream. The proposed project will not
impact the quantity or quality of water within the irrigation ditch. 017 C5.2 NE Grading Drainage Plan, 018 C5.3 Drainage and 019 C5.4 Storm Sewer
• There are no applicable watercourse setbacks.
• There is no outfall of Stormtech System #6 – this is an infiltration system.
• It appears that NE storm system is within buffer zone 1- There are no applicable
watercourse setbacks.
• There is no outfall of Stormtech System #6 – this is an infiltration system.
• The stormwater design report is included as item #009 in the application. The City of
Bozeman Stormwater Department reviews this document and they have approved this
plan.
• It appears that grading will occur to the wetland edge. I have not seen a sediment and erosion control document to prevent additional fill to the wetland. The stormwater design report is included as item #009 in the application. There are no stormwater discharges
to the wetlands (all stormwater is captured and infiltrated in surface ponds or
underground chambers). There are no fill slopes steeper than 4H:1V designed across the entire development so no erosion into the wetlands is anticipated. Slopes adjacent
to wetlands will be seeded with erosion control matting directly after construction to
prevent erosion. A Stormwater Pollution Prevention Plan will be in place prior to any construction on site. Stormwater best management practices will be established and
maintained to prevent any impacts to wetlands. The City Stormwater Division and
Engineering Department have reviewed these plans and the applicant will continue to coordinate with these departments throughout the development. 031 L101 Overall Landscape, 031 L102 Plant Schedule, and 033 L103 Park PlanSheet 009 NE Site Plan and 010 SE Site Plan
• There are no buffers on these figures – There are no applicable watercourse setbacks.
• It appears that trails in the park are within Zone 1 of the buffer and are not allowed –
There are no applicable watercourse setbacks.
• A separate plant schedule is required for buffers that state species that are native to
Montana. For instance, it appears that they plan to use Acer platanoides (Norway Maple)
within the buffer. However, this is a non-native tree. There are no applicable watercourse
setbacks. Non-native species can comprise up to 20% of species.
• It also appears that the plan has additional unnecessary fill in the NW portion of the park
There is no unnecessary fill in the NW portion of the park. The public roads are designed
to City local street standards and grade back to existing elevations.
• It is VERY clear in L103 that the trail and additional fill are placed in the wetland in the
NE portion of the wetland. I STRONGLY recommend that this path terminates on the
sidewalk to the west Agreed, the park improvement plans have been updated to remove
the trail from the NW portion of the wetland. The fill placed along the south side of Apex
Drive is necessary due to the required elevation of the street. The impacts from this fill
are accounted for (see item 011f Wetland Impact Exhibit).
Additional Comments
• I do not see details for Apex drive for culverts for the irrigation ditch. Nor do I see details
for the fill within the wetland crossing that will minimize impacts on the hydrological
connectivity to the downgradient portions of the wetland. I recommend the pervious
structural fill that was specified for the Arnold St. Extension. I also do not see an
assessment of cumulative impacts resulting from this project. The full construction plan
set for public improvements (Apex Drive) is provided after conditional site plan approval
is received (City Engineering and DEQ must approve public improvements plans prior to
construction). Pervious structural fill will be used for the culvert crossings. A perforated
culvert will be used at road crossings to ensure hydrologic connectivity downstream of
them.
Direct Impacts:
Right of Way Impacts*
Location Acres Square Feet Reason
Apex Drive/Gabriel Avenue 0.61 3,100 Required by City - Apex Drive/Gabriel Avenue
*ROW Impacts are those impacts required by City of Bozeman Zoning
Overall Project Impacts
Location Acres Square Feet Reason
Phase 2 Construction 0.36 2,445 site development
Indirect Impacts:
Apex Drive Crossing Install perforated culvert to convey water
Bennet Boulevard Crossing Install perforated culvert to convey water
Range 5 Apartments Wetland Impacts