Lake Texoma a large lake that straddles the Texas and Oklahoma border and teaches you about how the Army Corp of Engineers used this site to help mitigate flooding, shoreline erosion, and manage water runoff should the lake swell in the flood season. The earth cache area is only accessible off the rural road 91 off the 75 highway coming from Texas or Oklahoma, but parking is available nearby at the way point. Please note and comply with the park rules posted at the location if you park in the boat ramp you may need to pay a fee however there is free parking atop the hill closest to the waypoint.
There is no physical cache container to find; to log this earthcache, you will need to message or email us the answers to the questions below.
ORIGINS OF LAKE TEXOMA
It's clear how Lake Texoma got its name as it acts as part of the Texas Oklahoma border, but most agree that this area got its origins when the dam on the Red River was built in 1944 making Lake Texoma, the largest lake in capacity in the Tulsa District and the twelfth largest in the United State. The purpose of the dam is flood control, water supply, hydroelectric power production, river regulation, navigation and recreation. It is also one of the most popular Federal recreation facilities in the country, with more than 6 million visitors annually. Lake Texoma’s two main sources of water are the Red River from the west and Washita River from the north. Other notable sources include Big Mineral Creek, Little Mineral Creek, Buncombe Creek, Rock Creek, and Glasses Creek. Lake Texoma drains into the Red River at the Denison Dam either by controlled release or the spill way. Either way a lot of wind and river flow comes to the dam shore every year.
SALT BEDS IN THE RED RIVER
The Red River that formed Lake Texoma is a saltwater river due to salt deposits left over from a 250-million-year-old former sea that was in the current Texas-Oklahoma border region. As time passed, that sea evaporated, leaving salts deposits — mostly sodium chloride. Rock and silt eventually buried the deposits, but the salts continue to leach through natural seeps in tributaries above Lake Texoma, sending as much as 3,450 tons of salt per day flowing down the Red River. The problem with the water in the Red River is much of it is too salty and requires costly treatment, if it is usable at all. Due to this phenomenon, striped bass, a saltwater fish species, thrives in Lake Texoma. Lake Texoma is home to the only self-sustaining population of striped bass in Texas.
LAKE SHORE EROSION
It is somewhat inevitable that land on a lake shore eventually erodes into the lake, and that natural forces reshape shorelines. Rain loosens soils, gravity washes the soil and water down to rivers and creeks. Waves, boat wake, storm surges, and river currents can work to continually shift shore lines that surround a lake. Human development can amplify the natural process such as when a dam is placed in the path of a river. Saltwater from the Red River creates an interesting environment
SHORELINE MANAGEMENT PLAN
Shoreline Management Plans help to ensure that the water area, shoreline and adjacent public land of Corps of Engineers projects are managed to protect the environment and scenic beauty of our lakes for future generations.
One of the most common steps to preserve existing dams from erosion imitating nature, the second stone & vegetation rip rap. These two examples are visible from the coordinates.
Imitate Nature. In its natural state, the shoreline is able to perfectly protect itself against erosion. Imitating nature is the perfect way to help prevent erosion. Use native vegetation around the shoreline to help build structural integrity and prevent the land from breaking apart. The deep roots of these plants help protect the land from heavy rainfall and winds that may cause erosion.
Stone & vegetation rip rap. This particular method of shoreline stabilization should only be used if other, more natural methods have not worked or it is common knowledge from past projects an area will need hardening. This technique needs a stable underlying soil base and can be difficult to put in place. The basic idea is to lay the rip rap (hard quarry stones, or a combination of live vegetation and stones) in two layers. This technique allows for the shoreline to be stabilized while still providing some habitat for wildlife such as the fish that the lake holds in abundance.
A final thing you may notice if you are in the boat ramp area is that this lakes dam has a spill water to protect the dam and allow the Red River to rejoin its natural course in time of high wat. The flood control pool extends to elevation 645 ft (197 m). The lake has crested the dam's spillway at a height of 640 ft (200 m) five times - once in 1957, 1990, and 2007, and on May 24 and June 18, 2015. (USACE 2003a) The lake's previously highest elevation was recorded on May 6, 1990, at 644.76 feet. This record was broken on May 29, 2015, and the lake crested on June 1, 2015, at a new record elevation of 645.72 feet. The top of Denison Dam is at 670 feet.
LOGGING THIS EARTHCACHE: This earthcache was designed so it could be answered without referencing outside research.
To log this earthcache, message or email us and copy and paste these questions, along with your answers. Please do not post the answers in your log, even if encrypted. There's no need to wait for confirmation from us before you log, but we will email you back if you include your email address in the message. Group answers are fine; just let us know who was with you.
1. The name of this earthcache: Lake Texoma – Denison Dam ABEC #1
2. Observe: Look at the immediate sides of the dam and the nearby lake shore lines. Do you see erosion? Do you see the use of the two techniques the natural vegetation and the use of hard rip rap?
3. Observe: Look behind the boat ramp to the area that would act as the plain to the concrete spillway area. What is important about this area as a flood goes through?
4. What is the height difference between the top of the dam and the spill way?
Why not simply have the lake spill over the dam?
5. At the GZ there are plaques that talk about the history and engineering parts of the dam. The Spillway is one, what is one other and its role? SEND A PICTURE OF THAT SECTION FROM THE PLAQUE ONLY IN THE ANSWERS RESPONSE
Note if flooded this would look dramatic but be very dangerous and the spillway when even dry is dangerous due to the slope.
In the Log area
Send a picture of the Dam or your favorite part of the area. You are not required but you may be in the photos also to log this cache.
SOURCES
US Army Corps of Engineers, Tulsa-District-Lakes Oklahoma Lake-Texoma
Aqua Barrier Shoreline Stabilization Techniques
Lake Texoma Finally Over Spillway Posted: July 15, 2007 12:39 PM KTEN News
Lake Texoma Info". Towm-Mall.net. Town-Mall.net