About Us - Geyser Observation and Study Association
GOSA Store
Geyser Observation and Study Association - Transactions


Geysers of the World   

Geysers of Yellowstone   



  Riverside Geyser
Feature Type: Geyser
Geyser/Spring Type: Cone geyser

Upper Geyser Basin
Grotto, Riverside, Chain Lakes

Riverside is a cone-type geyser. Its interval is usually 5 1/2 to 7 hours, its height about 75 feet and its duration about 1/2 hour. The water phase of the eruption lasts about 20 minutes and is followed by a steam phase. Situated on the bank of the Firehole river at the base of a wooded hill, Riverside has one of the most picturesque settings of any geyser. Riverside's eruptions are highly bi-modal. Eruptions usually occur either about 1/2 hour before or 1/2 hour after the current average. No one know how to determine which of these two, the short interval or the long interval, will occur. If this could be determined, Riverside would be one of the most predictable geysers in the park.

What to look for:
You watch Riverside from a viewing area across the Firehole river from the geyser. From this position, Riverside's formation looks something like a chair. There is a vent high up on the back and another vent in the seat of the chair. Except for some minor splashing, the geyser erupts from the lower vent in the seat of the chair. About 1 1/2 to 2 hours before the eruption the main vent in the seat of the chair begins to overflow into the river. This overflow is variable. About an hour later, the small vents behind the main vent will begin to bubble and boil. The activity fluctuates but seems to build as time progresses. Finally a splash or two will be seen in the upper vent at the top of the chair back. One of these splashes from the upper vent will be large enough to spill water into the river, this usually starts the eruption.

Electronic Monitor Files
Riverside Geyser eruptions in 2005.TXTRiverside Geyser eruptions in 2006.TXT
Riverside Geyser eruptions in 2007.TXTRiverside Geyser eruptions in 2008.TXT
Riverside Geyser eruptions in 2009.TXTRiverside Geyser eruptions in 2010.TXT
Riverside Geyser eruptions in 2011.TXT 

Some of the temperature data used to derive the eruption times and durations used in this section were collected by Ralph Taylor under a National Park Service research permit, and the remainder was collected by personnel working for the Geology Department of the Yellowstone Center for Resources (including Ralph Taylor). The loggers are a combination of loggers owned by the NPS and Ralph Taylor. Analysis of the raw temperature data to extract the eruption data was performed by Ralph Taylor. The eruption time files on this website may be used provided that Yellowstone National Park is credited for the temperature data and Ralph Taylor is credited for the eruption times.

Activity in 2011
Activity in 2010
Activity in 2009
Activity in 2008
Activity in 2007
Activity in 2006
Activity Recorded by Data Logger - by Ralph Taylor  

Riverside Geyser has been monitored electronically using data loggers since 2000. This geyser is a visitor favorite, with regular eruptions lasting 20 minutes or so and a beautiful setting. We have had mixed success in monitoring the activity, however. The sensor is located so that it picks up the water temperature in the pool that forms around the vent when overflow starts. This gives both overflow duration and eruption start information (the latter inferred by the drop in temperature caused by the cessation of overflow once the eruption starts). Since the geyser is a cone-type geyser with almost all of the eruption water landing in the Firehole River, the sensor is not able to record eruption durations.

Over-winter logging has been problematic because of the difficulty of access to the geyser with snow and ice, and because our original logger location was covered by a thick layer of ice. Another nagging problem has been the displacement of the sensor from the pool which makes the temperature trace difficult or impossible to interpret. The result of all of the difficulties is a fragmentary record, which was still the case in 2006. In the winter of 2006-7 we were successful in obtaining over winter data at last. In 2007-8 we were unable to download the data for one six-week interval due to heavy snow cover. Over the winter of 2009-2010 we were successful with the exception of November, when a logger problem resulted in a month-long gap in data.

Activity in 2005  
The graphs here show the same information as described for the current year but cover all of 2005.

C 01 Riverside 2005 Summary.htm
Click for a larger image

Click for a larger image

Click for a larger image

Click for a larger image

Click for a larger image
Activity since 2000  
Riverside is known for its regularity. It is also known for being "bimodal"; that is, it has two different intervals at which it likes to erupt and switches between the two intervals. This effect is visible in the overall plot of interval vs time, shown at the right.
There has been some variation in the intervals, but they generally lie between 5h30m and 6h50m. Since July of 2003 there has been little change in Riverside's activity and intervals have remained largely between 5h50m and 6h50m.

Click for a larger image

Click for a larger image

Click for a larger image

Click for a larger image

This vintage Detroit Publishing Co. post card of Riverside Geyser, from the early 1900s, shows the geyser from a vantage point no longer accessible to the park tourist. Note the stagecoach on the old bridge just down stream from the geyser. The bridge has since been moved about 150 yards further down stream, so it know crosses the river near Fan and Mortar Geysers.

Please note - this site is currently under constuction. Please visit for more information.  Last update 01-29-2017

Home | Contact GOSA | GOSA Store | About GOSA | Transactions | Geysers of the World | Geysers of Yellowstone

Facebook Page Google+ Page YouTube Channel
Designed and Hosted by: Computer Point

2006 COPYRIGHT© 1997-2017 GOSA
All images © 1999-2017. All rights reserved. No form of reproduction, including copying or saving of digital image files, or the alteration or manipulation of said image files, is authorized without written permission