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This spring has always been a “childhood memory” of mine, my dad stopped here once and told us about how he came here when he was younger. Image Image

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Ricks Spring Cavern has been a traditional wayside stop for
generations.
Early settlers filled up jugs of spring water, until they
realized
the water was causing stomach and intestinal discomfort.
It was later discovered that what was thought to be a natural
spring was actually an underground diversion of the Logan
River.

Ricks Spring

Karst features in the Logan Canyon area are indicative of a
hydrologic system that is developed within more than 3,000 ft of
Paleozoic limestone and dolomite. Karst features in this alpine
region include large springs that discharge along major rivers,
losing streams in tributary drainages, caves and pits, blind
valleys, sinkholes, dolomite pavement, and surficial karst
(karren). Glaciation occurred above 8,000 ft during the
Pleistocene, resulting in destruction of karst landforms that
developed during interglacial periods (Wilson, 1976). Speleothem
age-dating, fluvioglacial deposits in caves, and deranged
topography indicate that existing karst features, particularly
caves, are largely remnants of former karst landscapes.

Karst systems in alpine terrains are substantially different
from those in relatively flat-lying strata in more temperate
regions. Characteristics of alpine karst systems include a large
component of vertical solution development and a thick unsaturated
(vadose) zone, steep hydraulic gradients, spring discharge that
responds primarily to snowmelt runoff, pit development in
high-altitude meadows, and cold-temperature dissolution of
carbonate rocks. To better characterize the hydrologic system in
this alpine karst, an investigation was begun to (1) determine
variations in discharge of selected large springs; (2) correlate
temperature and specific conductance of spring water with changes
in discharge; (3) determine recharge areas for the springs and
general directions of ground-water flow; (4) delineate ground-water
basin divides; (5) determine ground-water travel times; and (6)
evaluate the effects of geology on ground-water movement.

HYDROGEOLOGY

The Bear River Range consists in large part, of a thick sequence
of carbonate (limestone and dolomite) rocks that range in age from
Cambrian to Mississippian (Dover, 1987). The principal geologic
units in this area and approximate thicknesses are the Garden City
Formation (1,400 to 2,000 ft), Swan Peak Quartzite (200 to 400 ft),
and Fish Haven Dolomite (350 ft) of Ordovician age; the Laketown
Dolomite (1,500 to 2,000 ft) of Silurian age; the Water Canyon
Formation (425 to 600 ft), Hyrum Dolomite (850 ft), and Beirdneau
Formation (1,000 ft) of Devonian age; and the Lodgepole Limestone
(750 ft) of Mississippian age. Karst is more developed in the
Garden City Formation and Laketown Dolomite than in the other
carbonate units. All of the units, however, are capable of
transmitting water along dissolution-enhanced fractures, faults,
and bedding planes. The Swan Peak Quartzite is probably a barrier
to downward movement of water from the Fish Haven Dolomite to the
Garden City Formation in some areas and likely influences the
direction of ground-water movement. All of the formations make up
the upper part of a large regional structure, the Logan Peak
syncline (Williams, 1948) . The syncline plunges to the southwest
at about 15 degrees and rocks on the west limb dip at a
considerably steeper angle than those on the east limb. This
structural feature and associated fractures influence the movement
of ground water in much of the region.

Aquifer Recharge

Recharge to the carbonate aquifer takes place through point
sources (sinkholes and pits), as seepage losses through
fluvioglacial deposits that fill valley drainages, and as
infiltration along ridges and valley slopes. Sinkholes (dolines)
and pits are typically developed in high-altitude meadows where
snow accumulates and may persist throughout much of the year. Water
entering point sources moves vertically downward along
solution-enlarged fractures to principal conduits that channel
water to the springs. Pits range in depth from less than 100 to as
much as 300 ft, but many of these have been occluded by
fluvioglacial materials consisting primarily of quartzite boulders.
Fluvioglacial deposits also form a veneer over carbonate bedrock in
valley drainages. These deposits are very permeable and streams
typically sink into the streambed along distances of several
hundred yards rather than in distinct point sources such as swallow
holes. These losing reaches are probably related to fracture zones
within the underlying bedrock. Most streams in these alpine
drainages are fed by snowmelt runoff and, therefore, tend to be
seasonal. During periods of peak runoff, however, streamflow that
is not lost to the underlying bedrock continues down surface- water
courses to the Logan River. Infiltration of snowmelt along ridges
and valley slopes provides an additional component of recharge to
the aquifer and probably moves along diffuse pathways through the
fractured-rock matrix. Diffuse flow can be a significant component
of long-term storage in the aquifer and maintenance of base flow of
springs.

Discharge from Springs

Discharge from the carbonate aquifer is primarily from large
springs along the Logan River. The Logan River is the principal
base level stream for ground- water discharge in this part of the
Bear River Range. Three second magnitude (average discharge between
10 and 100 cubic feet per second (ft3/s))
and two third magnitude (average discharge between 1 and 10
ft3/s) springs, along with several
smaller springs, discharge along the north and west sides of the
river . These include Dewitt, Wood Camp Hollow, Logan Cave, and
Ricks Springs. Only one large (second magnitude) spring is known to
discharge along the south side of the river . Collective discharge
of the springs provides a substantial component of streamflow in
the Logan River. Wilson (1976) estimated that the combined flow of
Wood Camp Hollow, Logan Cave, and Ricks Springs could be as much as
20 percent of the discharge of the Logan River. Spring discharge
responds primarily to snowmelt runoff, with peak flow from late
spring to early summer and base flow during the winter months .

Figure 2. Hydrograph showing typical seasonal response of an alpine karst spring to snowmelt runoff, Dewitt Spring, Logan Canyon, Utah, January 1995 to January 1998
Figure 2. Hydrograph showing typical seasonal
response of an alpine karst spring to snowmelt runoff, Dewitt
Spring, Logan Canyon, Utah, January 1995 to January 1998 (Data from
City of Logan Water Department, written commun.,
1998).