Summer Prep for the LTRP:
Water Quality | Wild Iris | Bird Populations
Water Quality of Seattle Creeks and Lakes

Researchers

Lorena Calderon, Jennifer Davidson, Megan Foster, Remedios Guerra, Josephine Hendricks, Amber Pickett, Antonia Ramirez, and Mayra Rojas.

Introduction

Rural Girls in Science chose to come together to study water quality at four locations to compare the differences and similarities between two lakes and two creeks in the Seattle area. The lakes we studied were Green Lake and Foster Island. The creeks we studied were Thornton Creek and Ravenna Park.

We measured several water characteristics at these sites. What we measured was: Dissolved Oxygen, pH, Nitrogen, Temperature, Depth, Turbidity and Phosphate.

The purpose of study was designed to collect data, learn about water characteristics at these sites, and land use around the water. Since these bodies of water are such populated with humans to see if they had an effect on the four bodies of water that we have chosen to study for this project and found effects on what humans do to the water.

More or less this project was really interesting and when we thought we knew everything about water but then we had found out that we didn't know that much.

Materials and Methods

Dissolved Oxygen:

To measure oxygen we used a dissolved oxygen kit. The range of this kit is 0.2 to 20 mg/L.

Nitrogen:

To measure nitrogen we used a nitrogen kit. The range of this kit is 0 to 15 mg/L.

pH:

To measure pH we used two different kits. One of the kits was detoured by drops and the other by different strips of paper. The results from each kit were placed in separate categories.

Temperature:

To measured temperature we used a thermometer. There isn't really a range for temperature, but on the thermometer we used ranged from -20 to 110 degrees C.

Velocity:

To measure velocity we used a net, two different balls, stopwatch, & measuring tape to measure distance.

Turbity:

To measure turbidity we used a Secchi disk, with a diameter of 6 inches. The Secchi disk had nails on it and a thick string tied to it.

Smell:

To test smell we used water from the area we are testing, our noses, and a jar to put the sample of water in.

Color:

To test color we used a water sample, our eyes, and a jar to hold the water sample in.

Other:

We also surveyed the number of people, animals, cars, boats, and looked for litter.

RESULTS:
A Comparison of Creek and Lake Data

Legend

N=nitrogen (nitrates) DO=Dissolved Oxygen P=Phosphorus (Phosphates)

Temp.= Temperature V=Velocity Turb.=Turbity (Water transparency)

 

 

Creeks
Lakes
Conclusion
Toxic
Comments

N

2-5 mg/L

2-22 mg/L

Different

Greenlake

Greenlake was high because it was very populated the first time out.

DO

7-10 mg/L

6.5-11 mg/L

Same

No

Lakes are high because they have a lot of algae.

P

1 mg/L

1 mg/L

Same

No

polluted water is <0.1 mg/L

pH

7.5

8

Same

No

They are both in normal range.

Temp.

11C-15C

16.5C-19.5C

Slightly different

No

Lakes are warmer; they don't move as much as the creeks

Turb.

N/A

N/A

Different

No

Greenlake was clear 1/2 the depth and Foster Island 4/5