HomeMy WebLinkAboutMONTAVA - PHASE D CORE AND IRRIGATION POND - BDR240006 - SUBMITTAL DOCUMENTS - ROUND 2 - Responses (4)
May 31, 2024
Heidi Hansen
City of Fort Collins – Utilities
700 Wood Street
Fort Collins, Colorado 80521
Re: Proposed Drainage Outfall for Montava Phase D
Martin/Martin, Inc. Project No.: 19.1354
Dear Mrs. Hansen,
Thank you for your letter dated May 16th, 2024 in response to the Anheuser-Busch (AB) and Larimer & Weld
Irrigation Company (LWIC) Agreement and the existing Burlington Northern and Sante Fe (BNSF) railroad
stormwater outfall. We concur with the City’s opinion that the 1986 Agreement satisfies the permission to
discharge stormwater into the Larimer & Weld Canal. In response to the City’s concerns relative to the
adequacy of the existing BNSF stormwater outfall, we have the following reply.
Prior to receiving the City’s letter, Montava was successful in locating and cleaning the existing culvert under
the BNSF crossing, which feeds the point source outfall from AB lands west of the railroad Right-Of-Way as
identified in the 1986 Agreement. In accordance with city criterion, the following observations were made.
1.
Proposed Drainage Outfall for Montava Phase D
May 31, 2024
P a g e 2 | 2
Based on these drain times and the fact that Phase D detention Pond 427 will reduce runoff rates to 2-year
historic rates, the proposed development will not have an adverse impact on the volume or depth of the
inadvertent detention that occurs upstream of the BNSF railroad embankment.
Lastly, we concur with the comment that utilization of the existing BNSF outlet may not be consistent with
the Cooper Slough Drainage Master Plan for full buildout conditions of Montava and ultimately the Master
Plan improvements will likely need to get incorporated into the stormwater infrastructure of the
development. Montava is fully committed to implementation of the ultimate stormwater Master Plan
improvements required for buildout of the development, including all improvements needed for any
stormwater in excess of that allowed to be discharged into the L&W Canal by the 1986 Agreement. For now,
Montava would like to request that Phase D be allowed to utilize the existing BNSF crossing culvert pursuant
to the 1986 Agreement while parties work on any necessary updates to the Cooper Slough Master Plan and
Montava seeks a stormwater crossing agreement with LWIC for the future buildout of the development.
Please let us know if this request warrants further discussion or if you have any questions or require further
analysis to document the adequacy of the existing BNSF culvert crossing as a temporary outfall for Phase D
of Montava.
Sincerely,
Ryan D. Byrne, PE, CFM
Associate
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Duration (hours)
Montava - Drain Time at BNSF
(Overall Property w/ Only Phase D Developed)
100-Year 5-Year