Taylor County Geotrail: Tygart Valley River EarthCache

This Earthcache is part of the Taylor County Geotrail, a series of 11 geocaches launched in the Grafton area during Fall 2015.

Draining portions of five counties, the Tygart Valley River is an important source of water, recreation, and transportation for many West Virginians.

This EarthCache is located at Maple Avenue Playground on Maple Avenue on the western side of the river.

Tygart Valley River
The Tygart Valley River has its start high of Cheat Mountain in Pocahontas County. From there, is heads north through the Tygart Valley to Elkins before swinging west through Belington and Philippi. The river's name comes from the Tygart (originally Tygart's) Valley in Randolph County through which it flows.

Upstream of Grafton and this site, a large dam built by the U.S. Army Corps of Engineers in 1938 impounds the river to form Tygart Lake. The concrete gravity dam is 1,921 feet long and 209 feet thick at its base. While the lake is known for its recreational and flood control benefits, one of the major reasons for its existence was drought. In the 1930s, a severe drought led to problems operating the Monongahela River lock system for lack of water. Tygart Dam stores water that can be released to ensure stable navigation pools.

Below the Tygart Dam, the river flows through Grafton and past Valley Falls State Park. In Fairmont, it meets the West Fork River to form the Monongahela River, which flows north to Pittsburgh. A small section of the Tygart at Fairmont is navigable by virtue of Opekiska Lock and Dam on the Monongahela.

Claiming Credit for the Tygart County Geotrail
On the side of the deck facing the river, how many railing posts are taller than the top railing? Include the corner posts. The keyword is the number of tall railing posts, spelled out as a word.

Claiming Credit for this EarthCache
To complete this EarthCache, you will need to Maple Avenue Playground.

E-mail your answers to the cache owner. Do not post them in your log. You can log the find without waiting for a reply from the CO.

1. Describe the condition of the Tygart Valley River in front of the deck. Is it placid or swiftly flowing? What color was the water?
2. There are lots of large rocks placed below the deck. What is their purpose and what geological process requires their use? Look at the trees immediately across the river for a hint.
3. Looking at the site, how much higher would the water level have of the river have to rise before it would cause a flood?
4. Why, in this location, is there usable land on this side of the river and none on the other side of the river? (Think about your answer to Question #2.)
5. Tygart Dam is less than 2 miles upstream of this site. Out-of-banks flooding is unlikely at GZ, but on the downstream end of Grafton near Fetterman, the risk of flooding is greater. What is different between this site and Fetterman? See this topographic map for details:
   

Complete the whole geotrail!
This geocache is part of a series of geocaches (see them all) in Taylor County. As of June 2025, six of the original eleven caches remain. Find at least five to get a special Taylor County Geotrail wooden nickel! Fill out the codeword puzzle to receive your reward.