The Town of Estes Park was one of many Colorado communities that sustained significant infrastructure damage during the floods of September 2013. The flooding caused extensive damage to roads, bridges, utilities, homes and business in the Estes Valley. The flood along Fish Creek destroyed or damaged signification portions of the sanitary sewer, municipal electric and water lines, bicycle/pedestrian trail, stream channel, access roads to Fish Creek Road and Fish Creek Road itself. The most significant infrastructure damage occurred in the 4.5 mile Fish Creek Road corridor due to flooding conditions in the adjacent Fish Creek. Roughly half of the road was destroyed and utility service lines were severed leaving many homes without water, sewer, gas, and electric.

Larimer County, the Town of Estes Park, Upper Thompson Sanitation District and the Estes Valley Recreation and Park District have partnered to complete flood repair work along the Fish Creek Corridor from SH 7 at Mary’s Lake Road to Lake Estes/US 36. These Fish Creek Project Partners are working with the agencies providing funding: the Federal Emergency Management Agency, Colorado Department of Transportation and Federal Highway Administration to plan, design and build the improvements needed to repair the utilities, trail, Fish Creek Road and cross-streets connection to Fish Creek Road.

Matrix Design Group, as a subcontractor to HDR, is currently working with the Town of Estes Park, CDOT, FHWA, FEMA, and Larimer County to coordinate the final design and construction. Matrix is tasked with hydrology and hydraulics to facilitate restoration of public infrastructure. Matrix’s work includes defining the 15.9 square mile Fish Creek watershed, evaluating the history of flooding on Fish Creek, and obtaining all FEMA flood studies, models and floodplain delineations. Matrix utilized HEC-HMS to model the hydrology of Fish Creek and calibrate it to available gage records to publish an updated 100-year discharge.

Using this new flow rate and post-flood topography, Matrix is defining a new floodplain as a base condition for evaluation of infrastructure restoration and its impact on the floodplain. Floodplain impacts will be evaluated for alternatives to restore utilities, roadway, and trail. Using current codes and standards, the study will propose culvert sizes for all crossing structures. Matrix is responsible to complete a CLOMR application to obtain authorization for work within the floodplain.