Mountainside RV Park

AESI provided engineering services for Mountainside RV Park located west of West Yellowstone at the northwest corner of the intersection of Targhee Pass Highway and Circle Right Road. The property is accessed from Targhee Pass Highway via two (2) approaches. The project site is currently used for a Super 8 Motel as well as for an RV park, served by on-site water and wastewater facilities that are considered obsolete and in need of replacement.

As part of the requirements for upgrading the existing wastewater facilities (wastewater collection, treatment, and disposal), the project would involve significant disturbance of the existing RV Park, which according to USGS Aerial photos, dates back to the 1950’s and 1960’s. RVs have drastically changed since the original RV Park layout, a new RV park layout is being designed to accommodate today’s RVs. As part of the overall planning, redesign, and phasing of the overall site, the owner has planned to maintain the 225 licensed units (175 RV Spaces, 50 Tent Spaces), and will not exceed this number of spaces as part of the redesign. Discussions with the Montana Department of Environmental Quality confirmed that any proposal for additional RV sites would trigger Sanitation Act Review. However, the wastewater generation for proposed cabin sites would be consistent with an RV site, so the proposed new site layout incorporates a combination of RV sites, cabin sites, and tent spaces.

Field work performed includes site topographic surveying, records and site research of existing permitted and unpermitted water and wastewater systems, soils evaluations, test wells, groundwater monitoring, aquifer testing, and hydraulic gradient calculations. This project has involved careful planning and management in terms of evaluating wastewater replacement options, yet maintaining operations of the existing Super 8 Motel and keeping options available for modification of the existing RV Park layout. Several hundred acres adjacent to the RV Park are being purchased by the client which has caused a reevaluation of nearby wastewater collection, treatment, and disposal methods for the region, in an eff ort to allow the facility to maintain operations and income without shutting down the RV Park for the necessary proposed improvements.

Earlier work at Mountainside RV Park included stream crossing design and environmental permitting for the proposed bridge replacements along Denny Creek. The work proposed replacing two bridges and adding a new stream crossing.