Location

Cow Crap Sink is a karst window with a spring vent and a siphon vent at each end of the round pond. It is located just off Manson Pike at the Diary Farm owned and operated by Middle Tennessee State University, in Rutherford County, in Murfreesboro, Tennessee.

Description

Cow Crap Sink is a drinking pond for the dairy cows. It is also used to irrigate the nearby soybean field. The pond is approximately 100 feet below the surrounding uplands with a small stand of trees on the east side. The pond is nearly round and the diameter changes with changes in water level, from about 100 feet in diameter, down to less than 50 feet in diameter. An old partial fence of wood and wire bisects the middle of the pond, underwater at higher levels, exposed at lower levels. Limestone outcroppings rim the south and east side, with mud banks elsewhere. Grasses and tilled farmland surround the local area, but only for a short distance (a mile or less). Cow Crap Sink is nestled a few thousand feet from the junction of I-24 and Highway 840. The cave has been explored to about 1500 feet and continues on towards 840. The depth is a steady 60 feet. The cave is a solution tube about 10 feet in diameter although the entrance is a narrow crack barely wide enough for backmounted cylinders. This entrance to the spring is near the middle of the pond. The siphon entrance is equally narrow and lies at the east end of the pond. There is little or no breakdown and few places to tie off a line. The water is a murkey brown, with low viz (30 feet on the best days), contains floating cow feces, and sometimes the stench is eye-watering.

Discharge

October 20, 2007: Too slight to determine. No boil.

Analysis

Temperature is in Celcius (22C = 72F), TDS is Total Dissolved Solids, DO is Dissolved Oxygen, Nitrate is NO3+NO2 as Nitrogen, Nitrite is NO2 as Nitrogen, Phosphate is PO4, E. Coli (number of colonies per 100 mL) measured using Easy Coliscan method. All values are reported in parts per million (mg/L), except Turbidity (JTU's or meters). Turbidity measured in NTU in 2002 and in JTU or meters in later years, NTU of 10 is crystal clear, at 50 there is haze or "see-through milky." JTU is essentially centimeters of clarity, so 60+ or 100+ indicates crystal clear water. Secchi Disk is depth in meters (m). WQI is the water quality index, a summary figure (100 is best possible). Critter counts are subjective categories of Excellent, Good, Fair, and Poor, and are based on the number of individuals and variety of species.

Summary

Nitrates and Phosphate is a bit high, but there are no plants or algae in or on the water. Dissolved Oxygen is very high, typical of Middle Tennessee spring water in which the water does not spend much time underground. Rainfall fills local caves and causes dramatic boils. The major concern here is the high E. Coli count. EPA puts the limit at 500 colonies per 100mL for swimming (1,000 for boating) and we counted over 1,000 colonies. Additionally, we found over 2500 colonies of non-fecal coliform, and over 500 colonies of "other bacteria," indicating that Cow Crap Sink is just that, a cow's toilet bowl. Water samples taken from well inside the cave would be better. Past dives have indicated a very healthy crayfish population, and many southern cavefish.

National Association for Cave Diving, PO Box 14492, Gainesville, FL 32604, Telephone and Fax: 1-888-565-NACD (6223)