Kalamalka Lake has many unique features and the Kalamalka Lake interpretation site is well worth a visit. Plus the beauty of the lake walk can be quite awe inspiring. Getting to the lookout is a bit of a walk but it is flat all the way. The only reason it isn't a difficulty 1 is the distance involved. No motorized vehicles are allowed so you must access it by your own power. The shortest route is along the Okanagan rail trail starting at the parking area on Westkal road in Coldstream.
Kalamalka is often called the lake of many colours which is certainly true. Although it is often quoted as a translation of the native name for the lake, that part is not true. The Indigenous name for the lake was Chilutsus which means long lake cut in the middle.
One of the reasons Kalamalka lake stands out is because it changes colour with the season. Some days it is turquoise, others a dark blue and others every hue in between. Kalamalka lake is a marl lake which is quite rare . Marl is formed when calcium carbonate which is dissolved in the water, crystalizes into tiny white crystals. (The calcium carbonate came from a limestone deposit left when the Fraser Glacier receeded 10,000 years ago). These crystals reflect the sunlight and the colour of the lake depends upon how much marl is near the lake surface. Marl forms fastest in warm temperatures and once the marl forms it sinks and stops reflecting light. A series of chemical interactions trigger the formation of the marl and in Kalamalka lake this process starts in mid summer when phytoplankton in the lake raise the pH as they photosynthesize. Interestingly water quality improves during this time, as nutrients suspended in the water bind with the calcium carbonate to form the marl. This in turn results in a decline in algae.
Kalamalka is interesting for another reason too. Kalamalka is a very deep lake with a very thick sediment layer below it. Many people know that the Okanagan valley has a major fault zone running through it. Here the fault runs up the middle of Kalamalka lake. This is a very minor fault compared to the famous, major fault zone off Vancouver island, where the Pacific ocean tectonic plate is slipping under the North American one. Still, each year there are several small earthquakes along this fault zone. They are all minor but over the last 40 million years, the rock on the east side of the lake has moved upwards 10-15km relative to the west side. There is also evidence of 50 to 100km of horizontal movement
Source: https://okanaganrailtrail.ca/kalamalka-lake-learn-more
http://historynstuff.blogspot.com/2019/08/note-dr.html
In order to log this cache you must visit the Kalamalka Lake interpretation site and send the answers to these questions to the cache owner. Do not put the answers in the log of it will be deleted.
1. Looking at the colour grid on the sign. What colour(s) is the lake the day you visit. The day I visited it was mostly an E5 (where the E refers to the horizontal block and the 5 the vertical). Is the lake the same colour all the way across and why is this?
2. Where is the deepest part of the lake? How deep is the bedrock there?
3. How thick is the sediment layer (at its deepest) below the water and above bedrock?
4. Take a picture of the You are here sign located at GZ (send it with answers NOT with the log). What is the “you are here sign” depicting?
5. Is Kalamalka lake in a U shaped or V shaped valley? What caused this shape?