Under the Urban Drainage and Flood Control District’s
Master Planning Program, stormwater planning studies are
periodically conducted to assess detention, water quality,
and drainageway needs in watersheds across the Denver metro
area. A Major Drainageway Plan (MDP) is currently underway
for the Newlin Gulch watershed. The area was previously
studied in an Outfall Systems Plan, published in 1993 by
Kiowa Engineering Corp.Newlin Gulch originates in
unincorporated Douglas County, located along I-25 about 3
1/2-miles north of Castle Rock. The creek and its
tributaries flow northeast through areas of Castle Pines,
unincorporated Douglas County, and the Town of Parker before
joining Cherry Creek near Challenger Park in the Town of
Parker. The Newlin Gulch watershed area is approximately 15
square miles (see
study area map).
West of I-25, the upper third of the watershed was
recently annexed by the City of Castle Pines and is slated
for residential and commercial development. East of I-25,
the watershed includes the majority of the planned Canyons
development, also in Castle Pines. The middle third of the
watershed starts upstream of the new Rueter-Hess Reservoir,
operated by Parker Water and Sanitation District, and ends
at Mainstreet in the Town of Parker. A portion of the Parker
Homestead development is located in the watershed just north
of Rueter-Hess. The lower third of the watershed, located
north of Mainstreet, is nearly fully developed by the
Stonegate Village and Challenger Park Estates developments,
among others.
A key goal of the study will be to update hydrology based
on the most current land use information for existing and
future conditions and to assess impacts associated with
Rueter-Hess Reservoir. Flood hazard issues along Newlin
Gulch will be identified and recommendations developed to
address problem areas. Newlin Gulch is a sandy, ephemeral
channel that is highly susceptible to instability and
erosion. With the scattered development and large
undeveloped areas in the watershed, the study will place an
emphasis on minimizing the impacts of future development as
they relate to channel stability. Measures will be
considered to protect the channel from degradation and
preserve natural stream functions.
The primary project deliverable will be a Major
Drainageway Plan. The Major Drainageway Plan will include
conceptual design of recommended improvements in the
watershed, including estimated costs. The completed study
will serve as a guide for implementing drainage improvements
within the watershed. Intermediate deliverables will include
updated Baseline Hydrology and an Alternatives Analysis.
The project is funded by the Urban Drainage and Flood
Control District (UDFCD), Douglas County, and the Town of
Parker. Other stakeholders that will be invited to
participate in the process include the City of Castle Pines,
Parker Water and Sanitation District, the Colorado
Department of Transportation, and the Cherry Creek Basin
Water Quality Authority.