The Grand Prismatic Spring in Yellowstone

Having just returned from the trip of a lifetime which included a six day visit to both the Grand Teton and Yellowstone National Parks in Wyoming, I came across a wealth of nature's wondrous beauty. This was the perfect place for anyone keen on wildlife, nature, photography, riding and fishing.

Traveling with my camera, I wanted to find out more about the colorful prismatic springs that I had previously seen and read about in a National Geographic magazine, but since forgotten. The colors of this extraordinary pool are hard to believe - how are they made, what makes the colors and what is a prismatic spring?

The Grand Prismatic Spring, which measures 370 feet in diameter and 121 feet deep, is located in the Midway Geyser Basin in Yellowstone National Park, just a short distance from the famous Old Faithful geyser on the southern loop road. It's the largest hot spring in the entire United States, and third largest in the world behind Frying Pan Lake in the North Island of New Zealand and Boiling Lake in Dominica.

Created on 16 Aug 2013 for IMMINENT Orange

All photos © 2013 Rob Hemphill

...is one amazing geyser among so many others.

On our first day of touring the National Park we had only heard about the famous Old Faithful Geyser and Old Faithful Inn, and our general knowledge of what Yellowstone had to offer was so limited. But we were in for a magnificent surprise as around every corner was something different.

One minute the earth seemed to be on fire as steam rose from thousands of outlets covering hundreds of acres of ground; the next, geysers spouted boiling water and steam. The earth really is breathing producing those identifying sulfurous smells and deep sounds, and thank goodness it is. When it stops, perhaps in a million years or so, there will be a catastrophic earthquake causing destruction on a massive scale and threatening the world's existence.

If you're ever at Old Faithful take time to look at the old inn which was completed in 1904. It stands at seven stories high and includes a large stone fireplace and vast lobby area.

Old Faithful Inn - GPS Coordinates: N 44 27.606 W 110 49.823

As we approached the site by road, all we could see was the appearance of steam coming out of the ground all around, but where the prismatic spring was located the steam was in different colors, blue, yellow and orange. We were excited at actually being able to see this extraordinary place for ourselves and not as a picture in a book.

After parking the car and reading an information board about the area, various awesome statistics hit us. Continuing over a bridge, we faced two massive torrents of boiling water pouring over the ground and into the Firehole River. The water, having been heated by the magma of an active volcano deep beneath us, rises through fissures in the rocks to this surface spring at temperatures of 160°F or 70°C.

The information board with the orange bacteria mat in the background.

I said earlier that as we read the information board (pictured above), we were amazed by some of the facts of this pool.

Here they are:

1. Prismatic means brilliantly colored.
2. The vivid blue color in the center of the hot spring is due to sunlight being scattered by fine particles suspended in the water.
3. The yellow, orange and brown colors which encircle the hot spring and line the run-off channels are caused by thermophiles which are heat-loving microorganisms. These microbes contain colorful pigments which allow them to make energy from sunlight and so thrive in the harsh conditions of hot springs prismatic means brilliantly colored.
4. In 1839, a few fur trappers from the American Fur Company crossed over the Midway Geyser Basin and reported sightings of a "boiling lake" of roughly 300 feet in diameter, This was highly likely to have been The Grand Prismatic Spring.
5. The spring discharges approximately 560 gallons of 160°F (70°C) water per minute into the Firehole River nearby. This equates to over 800,000 gallons a day!

   And, not to forget Excelsior Geyser close by also discharging up to 4,500 gallons a minute or nearly 6.5 million gallons a day!!

   That's over 7,000,000 gallons of boiling water entering the river every day !

Next to the Prismatic Spring

This photo shows the run-off into the river, its position is marked on the graphic above.

With so much boiling water running into the river out of the Excelsior Geyser pool, it's no wonder that fish life thrives so well, not to mention the well-being of the animals during the winter months when Yellowstone is covered in snow. During this time the park is closed to visitors and only reopens again in May the following season.

It is known that many animals congregate over the warm areas of ground around the springs, pools and geysers, and unsurprisingly occasionally disappear forever.

In the late 19th century, Excelsior was an active geyser that erupted quite frequently with eruptions averaging about 100 feet high, and some exceeding 300 feet high and and 300 feet wide. It's thought that these powerful eruptions damaged Excelsior's internal plumbing system, so nowadays it boils as a productive hot spring for most of the time.

There are many hot springs in Yellowstone with names like Morning Glory, Abyss, Emerald, Sapphire, and of course Grand Prismatic. They all glisten under the sun in a myriad of colors across the national park's harsh volcanic plain. These springs are the most common of all hydrothermal features within the park area.

The way they work comes down to basic plumbing with no constrictions. The superheated water cools when it reaches the surface, then it sinks back down only to be replaced by much hotter water from below. This circulation process is called convection, and with this continual movement, the water is prevented from reaching the temperature needed for an eruption to occur.

Anatomy of a Hot Spring

Photo: Morning Glory Pool in the Upper Geyser Basin

Yellowstone as a marvel is more renowned for its geysers, grizzly bears and bison rather than its bacteria, but there is something special about the bacteria living in these hot springs.

The unusual species that use photosynthesis is called Chloracidobacterium thermophilum and it lives in the colorful matting of microbes drifting in the warmth of a hot spring. This species has two types of chlorophyll which allow it to thrive in microbial mats and also to compete successfully with the other microbes for light energy. DNA analysis has shown that their closest relatives live around Mammoth Hot Springs in the north of Yellowstone National Park, and also in hot springs, in Thailand and Tibet.

New bacterium found in microbial mats of Yellowstone

Odd Bacteria Found in Yellowstone Turn Light into Energy

Having seen mainly colorful aerial images of the Grand Prismatic Spring, we realized that in order to get that view we were going to have to work for it!

When you visit the spring and walk along the walkways around the area, it's possible to get up close and see the vibrant colors and experience the sulfur smells, but you'll only get a lateral view.

We knew we wanted to capture the spring from the optimal viewpoint, but had no idea of how to get to the hill on the far side. We could see people walking along a track, so knew access was available. So, one evening we spent time on the internet trying to locate the entry to this track. Google Earth came up trumps, and we found our place and planned our return visit two days later when the weather was better.

When we arrived, we set off like soldiers on a route march - we had a definite goal and nothing was going to stop us achieving it. After walking a considerable distance to a spot adjacent to the Prismatic Spring, it was time to start the climb up a well worn hill. Luckily fallen trees on the journey up created useful stopping points to sit and rest on (and break any slips or falls on the way down).

Puffing and panting, we eventually got to the top of the first little hill, the views were getting better, so more photos were taken. Wanting to get to the absolute highest view point, we continued upwards and got to the very top, and were rewarded with the view you see in the photo above. It was worth every step and made us appreciate this marvel all the more.

Looking across the bacteria mat to the orange and blue colors of the steam as it rises out of the spring.

The hill we climbed for the aerial views can be seen in the background.