Agenda Date: 07/21/2026
Subject:
Title
Resolution 52-2026: Approving the first amendment to an Intergovernmental Agreement with Mile High Flood District regarding design and construction of drainage and flood control improvements for Rangeview Gulch from South Platte River to Prince Street
Body
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From: |
James L. Becklenberg, City Manager |
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Prepared by: |
Brent Soderlin, Director of Public Works & Utilities |
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Sarah White, Water Resources Manager |
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Presentations: |
N/A |
PURPOSE:
Approval of the First Amendment to an IGA with Mile High Flood District (MHFD) for design and construction of drainage and flood control improvements for Rangeview Gulch from South Platte River to Prince Street.
LONG-TERM OUTCOME(S) SERVED:
Safe Community; High-Quality Governance; Sustainable Community with Natural Beauty
DISCUSSION:
Rangeview Gulch is a local floodplain within the City of Littleton. The floodplain forms north of the High Line Canal until its outfall at South Platte River. Rangeview Gulch passes through Ridgeview Park and is intercepted by the Englewood City Ditch. Rangeview Gulch then either overtops into Lee Gulch or over South Santa Fe Drive through the Meadowood Village Mobile Home Park.
The City of Littleton, in partnership with South Suburban Parks and Recreation District (SSPRD) and MHFD, are working on design alternatives for park improvements at Ridgeview Park, as per the 2023 Integrated Water Resources Plan. The Ridgeview Park Pond reconfiguration includes conversion of the existing retention pond to help mitigate odor and provide water quality. Interim construction is planned for 2026.
The City of Englewood is currently in process of piping City Ditch which alters the existing conveyance of Rangeview Gulch.
The City of Littleton, SSPRD, and MHFD, in conjunction with many grant funding partners, are constructing the Reynolds Landing Project near South Platte River. Reynolds Landing will have a floodplain terrace constructed for the eventual outfall of Rangeview Gulch.
With multiple projects occurring on the same floodplain within 1 mile of each other, it is prudent to look at these all as a complete project, to ensure one project does not create adverse impact on any other future projects and to ensure fiscal responsibility in completing overlapping projects with other funding partners.
The City of Littleton and MHFD have begun working on hydraulic analysis and interim design plans. Funds for design were encumbered with the original IGA. Full project design and construction costs are not known at this time. Preliminary cost estimates for the entire project range from $10-15 million. The City of Littleton is further exploring the State Revolving Funds as an additional funding source.
MHFD provides a Capital Improvement Program in partnership with the local jurisdiction to provide design and construction of drainage and flood control infrastructure. The local jurisdiction must provide a minimum of 50% funding contribution. Capital funds are provided on a yearly basis from an available funding pool. MHFD has available capital funds for the Rangeview Gulch Project.
The City of Littleton therefore desires to amend the IGA with MHFD as a financial partner for the design and construction of stormwater improvements from approximately Prince Street to the South Platte River.
BACKGROUND:
Ridgeview Park consists of the 0.7-acre Ridgeview Pond and a large area of turfgrass that is irrigated with potable water supplied by Denver Water. The park has historically been fed by seepage from the High Line Canal, overflow from private ponds upstream on the same drainage, and stormwater runoff. Declines in the volume of water run through the High Line Canal have decreased seepage into the pond. In 2023, the City of Littleton completed the Integrated Water Resources Plan which recommended 4 alternatives for the conversion of the pond at Ridgeview Park.
The city and MHFD are working on a design alternative to reshape Ridgeview Pond and create a floodplain channel similar to the other section of channel in the park. The reconfiguration of the pond will require significant grading, muck removal and installation of larger storm infrastructure into South Curtice Street. Pond/channel reconfiguration is anticipated for construction 2026 (permit dependent), as to benefit from the soil export from the Lee Gulch at Broadway Culvert Repair and Underpass Project (Littleton project #24-72), saving import and export expenses on both projects. This first phase of the Rangeview Gulch project is limited to pond and outfall reconfiguration only. Additional infrastructure needs downstream South Curtice Street are still being analyzed.
The City of Littleton and SSPRD have been working on conceptual design alternatives for Ridgeview Park improvements. An open house and community outreach survey was conducted in August 2024. Conceptual designs were presented along with an engagement board to help determine what park amenities are desired by the community. Design plans for the park are still ongoing.
Rangeview Gulch is a combination of street conveyance and storm sewer from the outfall at Ridgeview Park down South Curtice Street to Turtle Lake (Linhart Reservoir No. 2). Rangeview Gulch then conveys over swales along the railroad until its eventual outfall to Lee Gulch. Small flows are routed to Lee Gulch, large storms would overtop Railroad and Santa Fe, engulfing Meadowood Mobile Home Park as it outfalls to Lee Gulch Pond and the South Platte River. A portion of Rangeview Gulch from Turtle Lake to Lee Gulch has overland flows in the City of Englewood water supply ditch (“City Ditch”).
The City of Englewood is currently designing plans for the piping of City Ditch. Due to railroad conflicts, Englewood is unable to install the new water line in the railroad property and is proposing to use the existing easement alignment. As noted in the 1990 floodplain study “Flood Hazard Area Delineation Lower Dad Clark Gulch and DFA 0068” flows discharged from Turtle Lake historically went directly to South Platte River. However, due to the construction of the AT&SF Railroad embankment, these flows now go north along the east side of the railroad and discharge into Lee Gulch. The 1990 floodplain study “Outfall Systems Planning Lower Dad Clark Gulch and DFA 0068” provided recommendation for improvements to this crossing to get Rangeview Gulch to outfall at its historic location near Turtle Lake. Culverts have been installed under the railroad property and Santa Fe Drive This infrastructure was installed in 1997 but capped until a later date when financing was available. If capacity of the City Ditch is altered such that it no longer has capacity to convey low flows to Lee Gulch, it can cause adverse impacts to those homes adjacent to Turtle Lake and damage to the railroad embankment. It is proposed to work in conjunction with the Englewood piping project to connect the Rangeview Gulch flows to the installed culvert beneath the railroad west of Turtle Lake.
In 2014, the Breckenridge Brewery development granted a 40-foot drainage easement through the property for the future connection of the Railroad/Santa Fe culvert to the future planned outfall of Rangeview Gulch to the South Platte River at Reynolds Landing. Two additional 10 foot temporary construction easements were also granted for the construction of the drainage improvements (to be activated prior to construction).
Reynolds Landing Park is a 13-acre parcel along the South Platte River that currently includes an existing open space, the Superchi property (an abandoned house that the city acquired) and a stretch of ecologically degraded river. Littleton has partnered with Mile High Flood District, South Suburban Parks and Recreation and Arapahoe County since 2016 to begin transforming the space. In 2020, planning efforts began to restore the river. Through public engagement and expansion of partnerships, the project grew to incorporate the surrounding parkland and create a strong access to nature and serve as a gateway to the river. Phase I construction began January 2025. Later phase construction includes construction of a floodplain terrace for the eventual outfall of Rangeview Gulch.
The City of Littleton desires to amend the Intergovernmental Agreement with MHFD as a joint funding partner for the design and construction of the drainage improvements of Rangeview Gulch from Prince Street (Ridgeview Park) to South Platte River. The initial IGA was utilized for design; this amendment will provide capital funding for the interim pond reconfiguration and funding needed for improvements resulting from the piping of City Ditch. Capital Improvement Projects with MHFD require a minimum of 50% contribution from the local jurisdiction.
Prior Actions or Discussions
June 3, 2025: Council approved, per Resolution 59-2025, an IGA with MHFD for the Design and Construction of Drainage and Flood Control Improvements for Rangeview Gulch from South Platte River to Prince Street.
FISCAL IMPACTS:
Approval of this IGA amendment authorizes $750,000 contributed by the city and $750,000 contributed by MHFD for design and construction of the project. The total project cost has not been finalized, and it is anticipated that funds for construction will be added to this agreement through future amendments. Staff will continue to search for additional funding sources as final design continues. $750,000 will be funded from the Storm Drainage Enterprise Fund.
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Funding Source |
Funding Amount |
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City of Littleton Account 4200-313-78220 |
$750,000.00 |
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MHFD CIP Match Funding |
$750,000.00 |
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Total |
$1,500,000.00 |
STAFF RECOMMENDATION:
Staff recommends approval of the IGA.
ALTERNATIVES:
If not approved, the city would need to fund the project without the contribution from MHFD, and the project would be delayed until sufficient funds can be identified.
PROPOSED MOTION:
Proposed Motion
I move to approve Resolution 52-2026 approving the first amendment to an Intergovernmental Agreement with Mile High Flood District regarding design and construction of drainage and flood control improvements for Rangeview Gulch from South Platte River to Prince Street.