National Speleological Society Cave Diving Section

Guides

Name	NSS No.	Phone	E-Mail
Rob Anderson	22022	(386) 454-3143	randerson007(at)windstream.net
Doug Chappell	25394	(904) 614-1257	dleechappell(at)aol.com
Rick Crawford	26637	(386) 935-0079	odincrawford(at)windstream.net
Wayne Kinard	51952	(386) 497-3876	wayne(at)amigosdivecenter.com
Bill Main	20191	(386) 454-7132 (h) (352) 339-0361 (c)	hogarth(at)gru.net
Mark Messersmith	51952	(352) 870-3000	mm(at)gue.com
Jerry Murphy	33786	(386) 454-0349 (h) (386) 365-8569 (c)
Frank Ohidy	44570	(508) 740-7663	fno(at)windstream.net
Jeff Petersen	41820	(813) 431-4060	Jeff.petersen(at)us.pwc.com

Science Report for Wayne’s World Cave System
Hydro-Geo Environmental Research, Inc.

Wayne’s World Sink is located in Hudson, Pasco County, Florida, on approximately 15 acres of undeveloped land. The Sink is approximately 1500 feet east of the head of Cow Creek (a saltwater, tidally influenced creek) and approximately 3000 feet east of the Gulf of Mexico. The land that includes the sink is dotted by numerous water filled sinks and depressions and one small spring run typical of a karst setting. The water in the sinks and depressions is tannic from the degradation of organic material that is typical in a wetland environment.

The immediate area surrounding the property containing the Sink is residential and has numerous saltwater and brackish canals connecting the residences to the Gulf. The canals probably have also served to dewater many wetland and marshy areas so that they could be developed. As has been typical for many coastal areas of Florida that were developed prior to environmental concerns, the dewatering has over time lowered the hydraulic head of the Floridan aquifer; thereby, increasing salt water intrusion into the aquifer.

Hydrogeology

Wayne’s World Sink has formed in the Suwannee Limestone, which is at or near land surface in the vicinity of the Sink. The water in the sink and the cave system is brackish with saltwater intruding into the system through a deep saltwater tunnel. The sink is tidally influenced with a direct connection to the Gulf as the high and low tides are of approximately the same magnitude and at approximately the same time as corresponding tides in the Gulf.

• Typical passage is approximately 90 to 110 feet deep with thick reddish brown silt on the floor. Visibility is usually 2 to 5 feet due to tannic conditions. On occasion visibility may reach 20 to 30 feet. At depths shallower than 90 feet, the system is characterized as a spongework cave with porous walls that look like Swiss cheese. Below 90 feet, the limestone becomes dense and the system is an anastomatic cave, consisting of arrays of curvilinear tubes that commonly intersect forming closed loops.

• Part of the system is a siphon feeding Spring #822-241A behind Hudson Bowl. Flow to this Spring appears to be constant with discharge occurring at high tide. The survey of the cave shows that one passage that ends at a pile of breakdown is directly beneath some of the Spring vents. No accessible passage through the breakdown has been found. Thus no entry or exit is possible through the Spring. The discharge of this Spring has been estimated at 30 cubic feet per second at low tide (Florida Geological Survey, Report of Investigations No. 39). The land in the vicinity of the Sink can not supply recharge for this much flow, indicating some recharge from wetland areas to the east of U.S. Highway 19.

• The Deep (140 to 150 feet deep) Salt Tunnel separates two brackish water tunnels that appear to have different water sources. The Deep Salt Tunnel has a variable temperature from 73a! Fahrenheit (F) in the winter to 79a! F in the summer but it is always warmer than the surrounding brackish water tunnels. The Deep Salt Tunnel often has a milky appearance limiting visibility to 1 to 2 feet. The milky appearance is believed to be due to the presence of hydrogen sulfide. The brackish water tunnels separated by the Deep Salt Tunnel have had temperatures that frequently vary by 1a! F, which may indicate separate water sources.

• he Beyond (the brackish water tunnel beyond the Deep Salt Tunnel) is usually a spring (a diver swims into flow when entering this tunnel). Flow has been observed mixing with saltwater from the Deep Salt Tunnel but no siphon lead carrying the brackish water beyond the intersection with the Deep Salt Tunnel has been discovered. The survey shows that the Beyond has been pushed to the vicinity of an office building at the corner of US 19 and Hudson Ave. Residents have informed the dive team that in the past a sinkhole opened in the vicinity of the office and was filled in by the County. When the sink was filled, flow at Hudson Spring at the west end of Hudson Avenue decreased dramatically. It is possible that the Beyond is pirating flow that once discharged to Hudson Spring. There are undoubtedly numerous unexplored leads in the Beyond. This estimation is based on the fact that most of the exploration in this area was performed in tannic water with 2 to 3 feet visibility.

• Tornado Alley is an area of high flow and rock breakdown, which survey data have shown to be located directly beneath Spring #822-241A. No passage through the breakdown or access to the surface have been discovered at this time. On top of the breakdown pile there are two impassable vents carrying water to the surface while some of the water flows passed the breakdown pile into a narrow bedding plane that remains impassable in spite of numerous attempts to negotiate it.

• Even though it was discovered in the Spring of 1996 over a year after exploration began, the Main Street Tunnel is believed to be the primary passage. Main Street has considerably less silt than other brackish water tunnels in the cave. It is a strong siphon toward the Gulf at low tide and a strong spring inland at high tide. Swimming toward the entrance to the Main Street Tunnel, the direction of flow can abruptly change from spring to siphon. This may be a groundwater divide created at low tide with some water flowing toward the Main Street Tunnel and some water flowing toward Spring #822-241A.

• The Main Street G Tunnel is one of numerous leads off the Main Street Tunnel. While the Main Street Tunnel generally trends to the southwest, the G Tunnel trends to the northeast. The G Tunnel is a spring and the water is less tannic and cooler than the rest of the system. The G Tunnel is heading under a section of canal northeast of the Sink that is usually clear and is fed by seven small spring vents. It is possible that continued exploration will lead to cave passage with clearer water.

The hydraulic complexities of the system are only beginning to be understood. Additional exploration and survey combined with water sampling for key components such as chloride, sulfide, and total dissolved solids may provide some clues to the sources of water in the system.

Biology

The Sink, which is not connected to any other water body except through the cave system, contains an odd collection of saltwater and freshwater fauna including mullet, blue crabs, and freshwater bream, minnows, crayfish, and grass shrimp. Occasionally, catfish, mullet, and blue crabs have been observed within the cave system.

The cave system fauna include

• A troglobitic crayfish, Procambarus leitheuseri;

• A troglobitic isopod, Caecidotea sp. Isopods have been observed carrying offspring. One parent was observed carrying 40 offspring.

• Two troglobitic amphipods, Crangonyx. hobbsi and Crangonyx grandimanus.

• Small (0.5-inch tall tube sticking out of floor) feather duster worms, Family Sabellidae, have been observed at depths greater than 100 feet in areas with salinities that range from 15 to 25 parts per thousand (ppt). Vouchers of the feather duster worms are currently being studied. The majority are a small species in the subfamily Fabriciinae.

• Small white anemones (approximately 1-inch tall) have been observed in areas of the Main Street tunnel where the salinity is greater than 20 ppt. The anemones are found at penetrations greater than 2,000 feet from the entrance.

• Orange bacterial “jellyballs” are common throughout the system. They are most often observed near the halocline as they are denser than fresh water and lighter than salt water. At the entrance to the Deep Salt Tunnel just below the average halocline depth of 100 feet, the rocks in the cave are coated with a layer of this bacteria.

Summary of Hydrolab Data

January 1, 1997: The dive began with the water level in the sink near the low tide level. Conditions in the Sink at the surface were: temperature 21.12a! C; pH 7.43 standard units (s.u.); salinity 4.1 ppt; dissolved oxygen (DO) 2.18 milligrams per liter (mg/L); and oxidation/reduction potential 200 millivolts (mV). Salinity was the only parameter that changed significantly during the two dives. The salinity in the system is highly variable, changing with depth and with horizontal location (closer to or farther from the Gulf). The lowest salinity value was 4.1 ppt from the surface of the Sink. The shallow part of the cave system (depth less than 90 feet) had salinity readings ranging from 7 to 13 ppt. Salinity readings between 25 and 28 ppt were recorded in the deeper parts (110 to 113 feet deep) of Garyas tunnel, which leads to the Main Street tunnel. The highest salinity readings were 31 ppt from the Deep Salt tunnel.

The other parameters measured showed very little change in the cave system with the exception being the Deep Salt tunnel. Typically the pH in the system, including the Deep Salt tunnel, was between 7.4 and 7.6 standard units (su). Locations with a higher salinity typically had a slightly lower pH compared to adjacent locations with a lower salinity. The temperature in the system was generally 23.5a! C and the temperature in the Deep Salt tunnel was 23.9a! C. Dissolved oxygen concentrations were typically 0.6 to 1.0 mg/L in the system and 0.4 to 0.6 mg/L in the Deep Salt tunnel. The oxidation/reduction potential in the cave system was 200 to 260 mV. No distinct trend in oxidation/reduction potential variability was observed. This may be partly because this sensor takes longer to equilibrate as values in the environment change compared to the sensors for the other parameters that were measured.

January 5, 1997: The dive began with the water level in the sink near the high tide level. Conditions in the Sink at the surface were: temperature 21.10a! C; pH 7.15 su; salinity 4.1 ppt; dissolved oxygen (DO) 2.10 milligrams per liter (mg/L); and oxidation/reduction potential 276 millivolts (mV). Salinity was the only parameter that changed significantly during the dive. The lowest salinity value was 4.1 ppt from the surface of the Sink. The shallow part of the cave system (depth less than 90 feet) had salinity readings ranging from 9 to 16 ppt. Salinity readings between 16 and 19 ppt were recorded in the deeper parts (110 to 113 feet deep) of Garyas tunnel, which leads to the Main Street tunnel. Salinity readings were 18 to 20 ppt at the start of the Main Street Tunnel with readings as low as 6.9 ppt in shallow areas (depths less than 85 feet). Salinities were greater than 17 ppt in areas of Main Street where feather duster worms are found and were greater than 20 ppt in areas where anemones were present. The highest salinity readings were 25.9 ppt near a penetration of 2,000 feet in the Main Street Tunnel.

The other parameters measured showed very little change in the cave system. Typically the pH in the system was between 7.2 and 7.4 su. In the Main Street Tunnel, locations with a lower salinity typically had a slightly higher pH (7.41 su) compared to adjacent locations with a higher salinity (7.31 su). The temperature in the system was generally 23.5 to 23.6a! C and the temperature decreased to 23.1a! C at the maximum penetration in the Main Street Tunnel. Dissolved oxygen concentrations were typically 0.5 to 0.8 mg/L in the system. The oxidation/reduction potential in the cave system was 250 to 275 mV. No distinct trend in oxidation/reduction potential variability was observed. This may be partly because this sensor takes longer to equilibrate as values in the environment change compared to the sensors for the other parameters that were measured.

The differences between the pH readings, 7.4 to 7.6 su on January 1 and 7.2 to 7.4 su on January 5, are probably the result of drift in the instrument’s calibration and do not represent changes in the water quality.

Other Salinity Data

In February and April 1996, water samples were collected from various locations within the cave system and brought to the surface for analysis with a conductivity meter (please note that the Main Street tunnel had not been discovered in early 1996). The data collected during these events showed the water in the system to be generally 5 ppt fresher compared to the Hydrolab data collected in January 1997. This probably a reflection of rainfall amounts in the Hudson area as 1995 was generally a year of normal rainfall and 1996 generally had lower than normal rainfall. This is interesting as the crustaceans that inhabit the system (crayfish, amphipods, and isopods) are considered freshwater organisms and are living in areas with an average salinity of 15 ppt. The crayfish population appears relatively unaffected by the increase in salinity. Isopods, however, were numerous in early 1996 and are now scarce. Amphipods are observed infrequently; therefore, no determination on changes in their population can be made.

Special Thanks

Hydro Geo Environmental Research would like to thank the following people, agencies, and groups for their support of this project: Mr. Ken Romie and Mr. Quincy Wylupek of the SWFWMD for providing access to the Hydrolab; the National Association for Cave Diving (NACD) for providing funding for diving expenses; Arnold Jackson of American Underwater Lighting for providing materials to repair lights and equipment, which are frequently damaged on this demanding dive; Mr. Tom Perkins of the Florida Marine Research Institute and Mr. Kirk Fitzhugh of the Natural History Museum of Los Angeles County who are studying the feather duster worms; and Dr. Richard Franz of the Florida Museum of Natural History who is identifying crustaceans from the system.