Originally constructed in 1889, Mariano Dam is an earthen embankment approximately 1,300 feet long.
Mariano Crest and rehabilitated downstream viewed from south dam abutment.
The dam has a jurisdictional height of 23.6 feet and a total storage capacity of 5,570 acre-feet. The reservoir is a storage facility used primarily for irrigation purposes, owned and operated by Consolidated Home Supply Ditch and Reservoir Company. Located between West 1st Street and Southwest 14th Street, approximately one mile south of State Highway 34, in Loveland, Colorado.
The dam exhibited substantial seepage at several locations along the downstream toe of the embankment. A slope instability in the form of a longitudinal crack with displacement was observed.
Rehabilitation work was proposed to safely control seepage and strengthen the dam against potentially destabilizing movements. Geotechnical investigations conducted for this work indicated that severe seepage also occurred through the bedded limestone bedrock, which occurs beneath approximately the northern one-third of the dam.
Deere & Ault’s staff designed the necessary improvements for the dam. These included the modification of the downstream slope, including a stability toe berm and toe drain, extension of the outlet works to accommodate the toe berm construction, and pressure grouting of the limestone foundation.
Deere & Ault’s staff then provided the QA/QC for these improvements.
Client: Consolidated Home Supply Ditch and Reservoir Company