The Hidden River of High Park
When you are standing at the posted coordinates you will be on a bridge over a small pond in High Park. Would you believe me if I told you there was a massive ancient river that stretches all the way to Georgian Bay underneath your feet?
The Laurentian River
The Laurentian River is a once hypothetical water source that flows through Southern Ontario. This river predates ice ages and stretched from Lake Michigan and Lake Huron, up through Georgian bay and into Lake Ontario before heading out to the Atlantic Ocean via the Saint Lawrence River.
Through the various ice ages rocks, till and other glacial debris covered up the great valley and it's river. However with no obvious mouths the river was purely a theory for over a hundred years. The map from 1890 below shows an estimation of where the river would have run.
Discovery
It was only in July 2003 that the great river was discovered by complete accident!
While doing construction in High Park, crews had to drain out the Ridout and Howard Ponds. This area was once used for a mineral spa and had two deep wells for the baths. While digging the ponds out they found these two artesian wells which they capped. They then proceeded to dig an observation well and then BOOM! A massive gusher of water shoots up like a geyser!
The water shot 15 metres into the air! The drenched construction workers re-cap the well and all was quiet... until the capped artesian wells blew up too! They recapped those again. Then water started running through the ground itself! Hydrogeologists and engineers finally realized what they'd discovered, the Laurentian River System ran right under High Park. The water springing up like a geyser meant the water was being blocked some how and caused pressure to build up.
The image below shows the depth of the trench that this ancient river takes through the bedrock. 
Questions:
Please e-mail or message the answers to the following questions to me, which can be found at the posted coordinates. Do not post answers in your log.
- According to nearby information how deep is the river below you? What buried the river so deep?
- Take a look at the overflow pipe nearby, what colour are the rocks around the pipe? What causes the change in colour?
- Estimate how fast you think the water is flowing out of the pipe. Do you think the water flows faster now than when the river was first discovered in 2003? Why?
- (Optional) Take a picture at the pond, please do not post photos of the outflow pipe.
Sources - Highparknature.org, Lost Rivers.ca