Various parking options are available around town. A
screened fence surrounds the spring, but cutouts have been
provided to allow viewing of the spring and small
informational signs have been posted at various locations on
the fence.
The city of Paso Robles pretty much owes its existence to hot
springs. Throughout history and prehistory, people have come to the
area to make use of the various hot springs around town. For a
while in 1860s the area was one of California’s premier health
resorts. Currently there are still a couple of hotels that are
located at hot springs and another property allows inexpensive
public access to their hot springs.
Apparently, a geothermal source some 400 feet below the surface
is the source that heats the ground water. The exact nature of that
heat source has not been fully described in the references I
have.
The faults in the area are thought to play a significant part in
the movement of the ground water in the area, creating the area’s
hot springs. The springs and wells found in downtown Paso Robles
may be controlled by an inferred fault that runs through the south
end of town from the Rinconada Fault. This fault likely allows
artesian (water under pressure) to flow up to the surface as
springs.
The hot springs in the area also have a significant amount of
hydrogen sulfide, the rotten egg smell noted around the spring.
This compound is considered a contaminant should it reach the
sewage treatment plant or the Salinas River. This is one of the
challenges still facing the city in developing a final solution for
the restoring the parking lot.
In addition to hydrogen sulfide, the hot springs
are generally more saline that nearby cold springs and wells.
While a cause of the added salinity is not proposed in the
references, it could be from the ability for hot water to
dissolve more salts than colder water.
Prior to December 2003, this spring did not exist. The epicenter
of that earthquake was miles away on the coast, but shook up the
area enough to alter the ground water flow along the subsurface
faults forming this spring.
Unfortunatley, the paper signs that were attached to the fence
appear to have been removed so you can't find the answers to
questions 3 and 4. Logging requirements:
Send me a note with :
- The text "GC1FDYE Paso Robles Sulfur Hot Springs at City Hall"
on the first line
- The number of people in your group.
- Find out what caused the large hole in the parking lot.(sign
currently missing)
- How has the flow of the water from the spring changed since the
earthquake? (sign currently missing)
- Estimate the depth down to the level of the spring
water.
The above information was compiled from the
following sources:
- Chapman, Chase, Youngs; Geophysical Survery,
Paso Robles Geothermal Area, California, Part of the Resource
Assessment of Low- and Moderate-Temperature Geothermal Resource
Areas in California, Part of the Second Year Report, 1979-80 of the
U.S. Department of Energy – California State – Coupled Program,
November 10, 1980
- Informational Signs Posted at
Paso Robles City Hall Parking Lot.