Monday, October 28, 2013

Compass Directions, Scavenger Hunts, and the pH Scale

On 10/22/13, the Kinder River Spies and the 1st/2nd Grade River Spies participated in a water feature scavenger hunt. Our detectives used clues and compass directions to find water features in close proximity to Edison Elementary. I also wanted to gauge the River Spies endurance levels for a possible field outing - by foot - to Amazon Creek. We may have to wait on that one! 

The Kinder River Spies did a mini scavenger hunt, so we also had time to explore the pH scale with some common household items. We tested the following substances of varying pH: lemon juice (2), milk (6.5), water (7), baking soda (8.5), and soap (10.0).

pH stands for "the power of hydrogen". On a scale from 1-14, one represents the most acidic and fourteen represents the most alkaline. Pure water has a pH of 7.0. Most aquatic animals live in water with a pH range of 6.5-8.2.

Water Quality Investigations

On 10/15/13, all of the River Spies sampled for aquatic macroinvertebrates in Amazon Creek. The Kinder River Spies tallied diversity and abundance near the intersection of Amazon & Fox Hollow. The 1st/2nd Grade River Spies identified and counted aquatic macroinvertebrates in the Amazon Creek headwaters near Martin Street. 

Amazon Headwaters along Martin Street Trail
View downstream of the Amazon Headwaters site
Amazon Creek near Fox Hollow.

Macroinvertebrates are animals that lack a backbone and can be seen with the unaided eye. "Aquatic" refers to animals that spend most of their lives associated with bodies of water. These animals are excellent bioindicators - their presence, abundance, and diversity  indicates the health of a stream, river, lake, wetland, or other aquatic environment. Macroinvertebrates are grouped according to their tolerance to pollution. 

Fin discovers an aquatic snail.

Greta and Jayling identify an aquatic macroinvertebrate found under a rock. 

The 1st/2nd Grade River Spies also conducted water quality testing by measuring temperature, dissolved oxygen (DO), pH, and turbidity.

Learning how to sample for temperature, DO, pH, and turbidity

The Kinder River Spies rated the water quality as poor at the Amazon & Fox Hollow site. The 1st/2nd grade River Spies rated the water quality as fair at the Amazon Headwaters site. I loaded our data on to StreamWebs™  - an online water quality data base managed by OSU:

I entered our temperature, DO, pH, and turbidity data on the World Water Monitoring website:

Monday, October 14, 2013

Water Pollution, Surface Tension, and Macroinvertebrate Match Game

On Tuesday 10/8/13 the Kinder River Spies focused on water pollution
We asked and answered several questions: 
Where does pollution originate? Can we see all water contaminants with the unaided eye? How do pollutants affect eggs and nesting animals? 
The kids already knew a fair amount about potential water contaminants. 
They identified fertilizers, pesticides, motor oil, pet waste, litter, and excessive dirt as sources of water pollution.

Examining an oil soaked egg

After the River Spies had mentioned motor oil as a contaminant, we conducted an experiment to test how eggs (hard boiled) faired when immersed in oil (cooking oil). We peeled an egg after 10 minutes and then one after 30 minutes. The oil soaked through the porous shell membrane and coated the inside of the eggs. The shell of the egg that soaked for over 30 minutes was soft and disintegrating! 
The kids could easily relate the results of our experiment with the devastating effect motor oil can have on ground nesting animals.

The River Spies had a rare opportunity to "taste" an experiment in which invisible "pollutants" were dissolved in tap water. I added lemon juice, salt, and sugar to various cups and had the kids sample the mixtures. This simple demonstration introduces the fact that not all pollution can be seen. Clear water is not necessarily clean water!

On Tuesday 10/8/13 the 1st/2nd Grade River Spies practiced identifying aquatic macroinvertebrates and explored surface tension.
Earlier, I had collected some specimens from Amazon Creek so the River Spies could match real invertebrates with a corresponding identification sheet. Our young detectives demonstrated excellent powers of observation! 
Examples of a few invertebrates that we identified:

Blackfly Larva
Mayfly Larva

Caddisfly Larva
 We also guessed how many drops of water one could place on a penny before the water spilled over the edge. Surprisingly, some of the River Spies managed to fit over 100 droplets on the penny's surface. The kids deduced that water is "sticky". The polarity of water molecules causes them to stick together - the hydrogen atoms carry a positive charge and the oxygen atom carries a negative charge.

Drops on a penny

Sunday, October 6, 2013

Field Trips to Amazon Creek and a Rain Garden

On 10/1/13, the 1st/2nd Grade River Spies searched for aquatic macroinvertebrates at Amazon Creek. The recent rains meant deeper water and sloshy boots! 

The River Spies found dragon nymphs (invertebrates) and several juvenile fish. 

Nora & Levi. Nora was our star collector for the day!
The fish were temporarily placed in a holding bin with the dragonfly nymphs so we could better observe them. We soon discovered that a dragonfly nymph was "missing" or had been predated. We will know next time to separate our invertebrates from our vertebrates!

Greta, Jocelyn, and Lena inspect our samples.

 Our first field trip for the Kinder River Spies was to a rain garden at the Willamette Center (27th & Willamette Street). 

This rainscaping project is the first of its kind in Eugene. Commercial property owners, private investors, the City of Eugene, and the Long Tom Watershed Council (LTWC) have collaborated to retrofit an existing building to manage storm water. The building's proximity to Amazon Creek lends to the importance of reducing and treating runoff for healthier and safer urban waterways.

We used our senses of sight, sound, touch, and smell to make observations.

We recorded the water temperature at 12°C and measured the pH at 7.5.
For more information on the Long Tom Watershed Council and projects in our area, 
check out their website: