Yahkōhtēwin Storm Pond EarthCache

NOTE at earthcaches there is no physical cache, container or box to find ... instead there are earth cache logging tasks to answer and a photo to take for the log.  What is an earthcache? 

Earthcache tasks or questions:

1. One drainage swale contains a storm drain partway along the channel. Question: Why would engineers place a drain there? 

2. Slowing Water Flow.  The sign explains that water slowly drains toward the river.  Question: Why is slowing water important?

3. Choose one rock in either of the two rock swales at the storm pond that you find particularly interesting. Comparing it to the rock chart provided in the description, please describe the rock's colour, texture, mineral composition, and any special features. Did you know that is how Geologists determine the geological history of that rock?  

4. Please take a photo of yourself, your geocaching dog, or a personal item such as your GPSr &c to show that you were visiting  this "Yahkōhtēwin Storm Pond area"  (face not required)  This photo can be inserted into the log after sending answers into the CO.

DO NOT POST ANSWERS IN YOUR LOG.   Please don’t provide the answers when logging the cache online except for the photo, for the rest of the queries use the “Send answers” feature OR geocache mail the cache owner including the earth cache GC number,  title and the answers.    Please answer to the best of your ability. As long as you give it your best effort, we'll be happy to accept your responses so you can log your EarthCache!  You will probably find the answers you are looking for in this description page confirming what you are seeing at this Yahkōhtēwin Storm Pond EarthCache!   Please do not disturb the vegetation or remove any soil, rocks, plants, or wildlife from the area.

Exploring Stormwater, Wetlands, and Urban Geology

Welcome to Yahkōhtēwin Storm Pond! This EarthCache explores how engineered storm ponds help protect cities from flooding while also creating habitat for wildlife and wetland plants.

Yahkōhtēwin Storm Pond is a human-made landform designed to collect extra rainwater and melting snow so nearby streets, parks, and homes do not flood during heavy storms. Engineers created the pond by excavating a large bowl-shaped basin in a low-lying area of the city. The deep pond acts like a temporary storage area where runoff from surrounding neighbourhoods can safely collect after rainfall.

When rain falls onto rooftops, roads, sidewalks, and parking lots, the water flows along streets into catch basins and underground pipes. These storm drains carry runoff directly into the pond. During large storms, water enters the pond faster than it leaves, causing the water level to rise and cover more shoreline and grassy areas around the basin.

Two important engineered drainage swales help move stormwater toward Yahkōhtēwin Storm Pond (marked as waypoint 1 and 2) ( may also be called drainage swales, rock-lined swales, stormwater channels, or engineered drainage channels.) These rock-lined drainage channels were carefully designed to safely guide water downhill from higher areas of land into the pond. One drainage swale flows west to east from near Saskatchewan Highway 7. A storm drain was installed partway along this swale to help collect extra water and move it underground during very large storms or rapid snowmelt. The second drainage swale carries runoff from the southwest neighbourhood (Parkridge Park) toward the pond in a northeast direction.

These features are carefully designed parts of the stormwater management system. The downhill slopes of the swales help rainwater flow safely into the storm pond instead of flooding nearby streets or homes.

The large boulders and rocks serve several important engineering and geological purposes:

• They slow fast-moving stormwater flowing downhill after rainstorms or snowmelt.
• They reduce soil erosion by protecting the ground from being washed away.
• They help trap sediment, dirt, and debris before water reaches the pond.
• They direct water into storm drains, culverts, or the pond basin in a controlled way.
• They help stabilize slopes and prevent gullies from forming.

These drainage swales work similarly to natural creeks because both move water downhill, but the swales were carefully built by people using engineering designs and rock stabilization. By slowing the water flow, the swales also help dirt and sediment settle before runoff eventually reaches the South Saskatchewan River.

Google Satellite view of the Yahkōhtēwin Storm Pond 

The pond itself was carefully engineered with gentle slopes and clay-rich soils. Clay helps slow the movement of water underground because clay particles are very tiny and tightly packed together. This helps the pond hold water longer rather than allowing it to quickly soak away into the ground. The deep basin, clay-rich soils, and slow outlet pipes work together to reduce flooding and protect nearby homes, roads, and city infrastructure.

The interpretive sign explains:
“During major rainfalls, the water level in this storm pond will rise. Storm ponds protect property and homes from flooding. When it rains, the water drains into catch basins in the street that release into this storm pond. Water stored in the pond slowly drains back into the South Saskatchewan River through the city's storm-water sewer system.”

Slowing water down is very important. Slow-moving water helps prevent flooding and also allows dirt, sand, and sediment to settle out before the water reaches the South Saskatchewan River. If stormwater rushed quickly into the river, it could cause erosion and carry pollution downstream.

As you walk around the pond, you may notice wet mud, water marks, flattened grasses, or wetland plants growing near the shoreline. These clues show that the water level changes regularly after storms or spring snowmelt. The shoreline soils are often muddy, silty, or clay-rich, which tells us the water usually moves slowly enough for fine sediments to settle at the pond bottom.

Although Yahkōhtēwin Storm Pond was built by people, it shares some similarities with natural prairie wetlands or sloughs. Both store water and support wildlife habitat for birds, insects, amphibians, and plants. However, natural wetlands formed over long periods through natural geological and ecological processes, while storm ponds are engineered specifically for stormwater management and flood control.

Over time, older storm ponds can slowly begin developing some wetland characteristics. Wet soils may remain saturated long enough for oxygen levels to become very low. These wet, low-oxygen soils are called hydric soils. Hydric soils are often dark brown or black because of decaying organic matter and may sometimes produce a sulfur or “rotten egg” smell. Wetland plants called hydrophytes, such as cattails, sedges, rushes, or willows, may begin growing along shallow pond edges where soils stay wet for long periods.

Storm ponds do not always meet the scientific definition of a true wetland because their water levels often rise and fall quickly between storms. However, over many years, standing water, decaying vegetation, and accumulated sediments can slowly create darker, low-oxygen soils where wetland plants and microorganisms thrive.

As you explore the pond, look carefully for signs of erosion along the shoreline. Fast-moving water, waves, wind, ice, and loose soils may slowly wear away pond banks and wash sediments into the basin. Engineers use gentle slopes, drainage swales, rocks, and vegetation to help stabilize the shoreline and reduce erosion.

Yahkōhtēwin Storm Pond also provides important habitat for urban biodiversity. Birds, insects, frogs, aquatic invertebrates, and wetland plants may all use the pond for food, shelter, nesting, or breeding habitat. Even though the pond was built for stormwater management, it has gradually become part of Saskatoon’s urban ecosystem. 

To support the city’s ongoing master planning, please use the free iNaturalist app on your smartphone to record and share observations of plants, animals, and other signs of life you encounter. The free Merlin Bird ID app can help you identify bird songs and calls in the area, making it easier to recognize the species living around the pond.  To help identify the rocks in this area, you can use the free smartphone app Rock Identifier (by Next Vision Limited), or Rock Check which allows you to take a photo of a rock and receive likely matches based on its visual features.

This EarthCache demonstrates how geology, engineering, water movement, soils, and ecology all work together in modern cities. Yahkōhtēwin Storm Pond and its engineered drainage swales protect people from flooding while also helping support wildlife and wetland-like habitats within the urban environment.

From Coral Seas to Granite Highlands

Reading the Rocks: A Geological Guide to the Yahkōhtēwin Storm Pond

The rock-lined swales, riprap channels, and boulder features throughout the Yahkōhtēwin Storm Pond are more than just engineering structures. While these rocks help slow stormwater, reduce erosion, and trap sediment, they also serve as a fascinating outdoor geological museum. The stones displayed here tell stories of ancient volcanoes, tropical seas, mountain-building events, glaciers, and the immense forces that have shaped our planet over billions of years.

Visitors can identify three major rock groups: igneous, metamorphic, and sedimentary rocks.

Igneous Rocks: Born from Fire

Igneous rocks formed when molten rock cooled and solidified.

Granite
Look for coarse-grained rocks with a "salt-and-pepper" appearance. Granite commonly displays white, pink, gray, and black mineral crystals that are large enough to see with the naked eye. The pink colour often comes from feldspar, while the glassy gray grains are quartz.

Diorite
Often called the classic "salt-and-pepper" rock, diorite contains contrasting black and white mineral crystals. It is generally darker than granite and lacks the pink feldspar commonly found in granite.

Basalt
Basalt is usually dark gray to black and much finer grained than granite or diorite. It formed from rapidly cooling lava flows and may appear dense, heavy, and uniform in colour.

Metamorphic Rocks: Changed by Heat and Pressure

Metamorphic rocks began as other rock types before being transformed deep within Earth's crust.

Gneiss
One of the most distinctive rocks in the collection, gneiss displays alternating light and dark bands that may resemble ribbons or layers. Colours often include white, pink, gray, black, and sometimes reddish tones. These bands formed under tremendous heat and pressure during mountain-building events.

Quartzite
Quartzite is typically white, light gray, cream-coloured, pink, or tan. It has a sparkling appearance because it consists largely of tightly fused quartz crystals. Quartzite is extremely hard and often breaks across grains rather than around them.

Sedimentary Rocks: Ancient Oceans, Rivers, and Shorelines

Sedimentary rocks form from accumulated sediments, minerals, and biological remains.

Limestone
Usually cream, tan, gray, buff, or light brown, limestone often contains visible fossils, shell fragments, or subtle layering. Much of Saskatchewan was once covered by warm tropical seas where limestone accumulated from marine organisms.

Coral Fossils
Some limestone specimens contain fossilized coral colonies. Look for honeycomb patterns, circular structures, or intricate geometric designs that reveal the remains of ancient reef-building organisms that lived hundreds of millions of years ago.

Sandstone
Typically tan, reddish-brown, yellow, or light gray, sandstone is composed of sand-sized grains cemented together. You may be able to see individual grains on weathered surfaces.

Conglomerate
This rock is easy to identify because it contains rounded pebbles and stones cemented together within a finer matrix. It records ancient rivers, beaches, or high-energy environments where moving water transported larger rock fragments.

Gypsum-Bearing Rocks
Gypsum often appears white, cream-coloured, pale gray, or translucent. It forms when mineral-rich waters evaporate, leaving behind sulfate minerals. Saskatchewan is well known for its extensive gypsum deposits.

Minerals and Special Features

The rocks also contain a variety of beautiful minerals that add colour and texture.

Quartz
Appears as glassy, translucent, white, smoky gray, or clear crystals. Quartz often sparkles in sunlight and is one of the most abundant minerals on Earth.

Biotite
A dark brown to black mica mineral that forms shiny, reflective flakes. Biotite commonly occurs in granite and gneiss.

Fluorite
Often found in shades of purple, green, blue, yellow, or clear crystal masses. Fluorite can be one of the most colourful minerals in the collection.

Red Jasper
A striking deep red to reddish-brown variety of quartz coloured by iron oxides. It often has a smooth appearance and stands out immediately among lighter-coloured rocks.

A Journey Through Deep Time

The boulders surrounding the Yahkōhtēwin Storm Pond represent geological processes spanning more than a billion years. Some originated within the ancient Canadian Shield, while others formed in tropical seas that once covered the Interior Plains of North America. Many were transported and deposited by glaciers during the last Ice Age, eventually becoming part of Saskatchewan's landscape.

Today, these rocks perform an important environmental function by protecting stormwater infrastructure. At the same time, they offer visitors a chance to explore Earth's history through colour, texture, fossils, minerals, and structure. Every boulder has a story, and together they reveal a remarkable geological journey through deep time.

Rocks of the storm pond rock-lined swales

	Consisting of Gneiss, Diorite, Limestone, Basalt, Quartzite
	Limestone, Gypsum, Quartzite, Coral
	Gneiss, Diorite, Limestone, Granite, Basalt
	Granite, Gneiss, Coral, Basalt, Coral
	Gneiss, Granite, Diorite, Sandstone, Quartzite
	Conglomerate, Fluorite, Limestone, Quartzite, Granite
	Limestone, Gypsum, Quartzite, Gneiss, Petrified Wood
	Diorite, Limestone, Gneiss, Granite, Quartzite
	Limestone, Coral, Gypsum, Quartzite, Basalt.    Why Do Limestone Rocks Have Holes? Limestone often contains holes because it formed in ancient oceans. Some holes are the remains of fossils such as shells, corals, or burrows left by marine organisms. Others formed when slightly acidic rainwater dissolved parts of the limestone over time, creating small pits and cavities. These holes provide clues about the rock's history and the ancient environments in which it formed.
	Limestone, Quartz, Gneiss, Quartzite, Sandstone
	Diorite, Gneiss, Granite, Basalt, Limestone
	Gneiss, Biotite, Limestone, Basalt, Quartzite

Image Hydric soil does form into a ball, is extremely sticky, and hard to work.

Engineered storm pond soils, and natural wetlands soils

Clay soils of the engineered storm pond can begin developing into hydric soils when they remain saturated with water long enough for oxygen levels in the soil to become very low or absent. Simply having clay does not automatically create hydric soil, but clay helps because it slows water movement and drainage.

Several important things must happen:

1. Long-Term Saturation
   The soil must stay wet or waterlogged for extended periods during the growing season. In wetland science, the upper soil layers are often saturated for at least 15 consecutive days or longer.
2. Oxygen Becomes Limited
   Normally, air fills spaces between soil particles. When water fills those spaces instead, oxygen cannot move easily into the soil. This creates anaerobic conditions, meaning low-oxygen or no-oxygen conditions.
3. Microbial and Chemical Changes Occur
   Microorganisms living in wet soils begin using up the remaining oxygen. Different chemical reactions then change the soil color, chemistry, and smell.
4. Organic Matter Builds Up
   Dead plants, roots, algae, and other organic materials slowly accumulate because decomposition happens more slowly in low-oxygen environments. This can turn soils dark brown or black.
5. Wetland Plants Become Established
   Hydrophytic plants such as cattails, sedges, rushes, reeds, or willows begin growing in the saturated soils. Their roots further influence the soil environment.
6. Hydric Soil Features Develop
   Over time, the soil may show:
   • Dark organic-rich layers
   • Gray or bluish colors from reduced oxygen
   • Rust-colored mottles from changing iron chemistry
   • Sulfur or “rotten egg” smells
   • Sticky, muddy textures

In places like Yahkōhtēwin Storm Pond, compacted clay soils help retain water. If shallow pond edges remain wet repeatedly over many years, some areas may slowly begin developing hydric soil characteristics even though the pond originally started as an engineered stormwater basin rather than a natural wetland.

For safety reasons, please do not enter the storm water pond for this following soil test, but look at the characteristics of "clay".  

Image Comparing soil to a Munsell Soil Chart

GLOSSARY

Yahkōhtēwin (also Wâhkôhtowin,wahkohtowin).  from Cree/nêhiyawēwin teachings about relationships, kinship, interconnectedness, and responsibilities among people, communities, animals, land, and nature.

The most commonly published English translation of Wâhkôhtowin is:

• “kinship”
• “everything is related”
• “the interconnectedness of relationships, communities, and natural systems”
• respect,
• and reciprocal responsibility with all living things.

In a rough translation, yahkōhtēwin / wâhkôhtowin can be understood as:

“We are all connected and responsible for one another and the natural world.”

This teaching aligns beautifully with the purpose of places like Yahkohtewin Storm Pond, where water systems, wildlife, plants, soils, people, and urban infrastructure are all interconnected within one living system.

Congratulations to Arkanada110 on achieving the First to Find (FTF) on this EarthCache! Thank you for being the first to explore this geological adventure and for helping celebrate the fascinating minerals, rocks, and geological history that make Saskatoon's landscape so remarkable.