FLOOD02077

• County: Larimer
• Community: Larimer County
• Stream Name: Lawn Lake Dam
• Title: Hydrology, Geomorphology, and Dam-Break Modelling of the July 15, 1982 Lawn Lake Dam and Cascade Lake Dam Failures
• Date: 1/1/1983
• Prepared For: State of Colorado
• Prepared By: USGS
• Floodplain - Doc Type: Flood Documentation Report

The Fall River flows into Cascade Lake at the east end of Horseshoe Park,
Cascade Lake, located about 5,3 mi west of Estes Park, was an artificial lake
privately built in 1908 and obtained by Estes Park for power generation in
1945, Downstream from Cascade Lake, the Fall River gradient steepens again to
9 percent as it flows through a series of Pleistocene terminal moraines and
into Aspenglen Campground (fig. 2).

Downstream from the Estes Park powerplant, at an elevation of about
8,000 ft and about 1 mi downstream from Cascade Lake, the Fall River valley
narrows noticeably, marking the probable maximum extent of Pleistocene glacial
advances (Richmond, 1960; Jones and Quam, 1944), Below 8,000 ft, the Fall
River flows down a relatively steep and narrow valley bordered by numerous
bedrock outcrops and thin, small, discontinuous flood plains, The Fall River
joins the Big Thompson River in Estes Park and then flows 0.7 mi before
entering the west end of Lake Estes. Lake Estes is a large reservoir, formed
behind Olympus dam, completed as part of the Colorado-Big Thompson project by
the U.S, Bureau of Reclamation in 1948.

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Fall River

J,. ~Bi9 Thompson RilJer

4 5 6 7 B 9 11 12
DISTANCE DOWNSTREAM FROM LAWN LAKE DAM, IN MILES

13

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Figure 2.--Long profile of flood path of the water from Lawn
Lake dam and Cascade Lake dam failures. Vertical exaggeration
10,5 times.

7