Experiment Title: Water Unit-Runoff

Purpose/Objectives:

Objective 3- to recognize that different types of soil have different saturation capacities.

Objective 5- to recognize the relationship between soil capacity to retain rainwater and flooding problems.

Materials and Equipment:

·      1 Standard metal paint tray 

·      3 Standard metal paint tray liners 

·      1 Piece of ~8”x15” fine door mesh 

·      2 Pieces of sod 3”x5” each one

·      1 (250 ml =~1cups) beaker

·      Measuring tape

·      Turkey baster

·      1 tile

·      Calculator

·      Lab coat

Method:

1.     Use the scissors to cut a piece of mesh that covers the inside area of the tray liners (~8”x15”) 

2.     Bend approximately 3 inches of one side of the mesh.

3.     Place the liner on the metal paint tray.

4.     Place the mesh piece on the liner with the bend end towards the bottom part of the tray (the part that is not raised- where the paint would collect). 

5.     Fold the surrounding upper part of the mesh around the raised part of the set up.

I.               H₂O RETENTION

Rainwater retention of pavement:

1.     Place the ceramic floor tile upside down on the mesh.  

2.     Apply 250mls of tap water to the tile using a beaker.

3.     Use the turkey baster to collect the water from the bottom of the tray.

4.     Transfer it to the beaker and compare this quantity to the initial quantity (250 mls).

Data collection

Equation #1:

                        (250 mls) – (the  amount you obtained from collection) = the amount of water absorbed by concrete

Use the form in the results section below to type in your data. 

Rainwater retention of grass:

1.     Turn the sod so that the soil and roots are facing upwards. Use the measuring tape to measure a 6”x10” piece. Safely use the exacto knife to cut the piece; this process might require you to run the knife several times through the same cut before the piece of sod is released. (** This step requires help to cut the sod pieces—it might have to be done outside since it can get messy). 

2.     Cut the 6”x10” piece in half (3”x5”) for both experiments. 

3.     Place a 3”x5” piece of sod on the mesh, making sure that one of the pad’s sides rests against the bent side of the mesh.

4.     Measure 250 mls of tap water and pour it SLOWLY on the piece of sod making sure to COVER THE WHOLE AREA. Small pieces of soil will come out with the water; the mesh will trap bigger pieces.

5.     Use the turkey baster to collect the water from the bottom of the tray. Try avoiding large amounts of soil that filtered through the mesh. Transfer it to a beaker and compare this quantity to the initial quantity (250 mls).

Data collection:

Equation#2:

                    (250mls) – (the amount you obtained from collection) = (the amount of water absorbed by the grass)

Use the form in the results section below to type in your data

                 II.             H₂O RETENTION OF OTHER SOIL TYPES:

Materials and Equipment:

Use the same materials as I. H₂O RETENTION AND the following additional materials:

·      Coffee filters depending on the soil type chosen for the optional exercise

·      Thoroughly rinse the mesh piece used on I. H₂O RETENTION

·      Standard metal paint tray liner

·      Soil of choice close to the size of the piece of sod used in I. H₂O RETENTION –grass-(for comparison purposes)

**This step might require extra filtration depending on the soil type. For example, sand might require a coffee filter placed between the mesh and the sample**

1.     Use the scissors to cut a piece of mesh that covers the inside area of the tray liners (~8”x15”) (**This step requires help to distribute mesh to groups).

2.     Bend approximately 3 inches of one side of the mesh.

3.     Place the liner on the metal paint tray.

4.     Place the mesh piece on the liner with the bend end towards the bottom part of the tray (the part that is not raised- where the paint would collect). 

5.     Fold the surrounding upper part of the mesh around the raised part of the set up.

6.     Measure 250mls of tap water and pour it SLOWLY on the piece of soil making sure to COVER THE WHOLE AREA

7.     Small pieces of soil will come out with the water; the mesh will trap bigger pieces.

8.     Use the turkey baster to collect the water from the bottom of the tray. Try avoiding large amounts of soil that filtered through the mesh. Transfer it to a beaker and compare this quantity to the initial quantity (250 mls). The difference between these two quantities is the amount of water that was absorbed by the soil piece. 

Equation #3:

                     (250 mls of water) – (the amount you obtained from collection) = (the amount of water absorbed by soil type)

Use the form in the results section below to type in your data

The difference between the water absorbed and the initial quantity of water applied (250 cups) will vary depending on the soil characteristics. 

RESULTS FOR I AND II:

2. Use Excel to create a bar graph showing the different amounts of water absorbed by all the soil types you used and the concrete sample.  Place concrete/soil types on the x-axis and volume on the y-axis.

3. Input the results you obtained in question 1 into the Google form below

III.           NUTRIENTS:

Materials and Equipment:

Use the same materials as I. H₂O RETENTION PLUS the following additional materials

• New piece of ~8”x15” fine door mesh
  

• Osmocote fertilizer 

• Nutrient testing equipment
  

Method:

PHOSPHOROUS

Phosphorous-Interpreting your results:

The Kansas Department of Health and Environment (KDHE) has determined that levels of phosphorus greater than 0.1 ppm can have a negative effect on aquatic life. Most large detections of phosphorus occur right after an addition of phosphorus from some source (for example, just after heavy rain or just after a wastewater treatment plant has discharged treated water). If you find a concentration of phosphorus larger than 0.1 ppm, you should note on your field sheet that there was most likely a recent addition of phosphorus. Perhaps from your observation notes, you can even figure out where it is coming from! If you are testing a river at flood stage, there could be phosphorus from many different sources combining to make the concentration larger. If you see agricultural fields all around, you may guess that the phosphorus is coming from fertilizers and manures. Use your observations to guess the most likely source(s) of phosphorus for your testing site. Once the source is isolated, people can begin figuring out how to reduce the amount of phosphorus going into the water.

NITRATE

( Click Here for Nitrate, Nitrite, Ammonia Usage of Test Strips and Interpretation of results)

NITRITE

AMMONIA

pH

1. Dip a strip into the water that collected at the bottom of the tray and remove immediately.  
2. Do not shake off the excess water
3. Wait 15 seconds
4. Compare the result with the color chart provided with the bottle and record the pH
   

pH allows you to compare a water sample’s pH to the neutral standard pH 7. According to the Kansas Department of Health and Environment (KDHE), the pH levels in a water sample should be between 6.5 and 8.5. 

Minerals present in soil, streambeds, or the bottom of a lake dictates the starting pH and the buffer capacity.

Acid rain, decaying plant matter, and mining sites close to the target body of water can greatly decrease the pH level of runoff.  Making the water more acidic.

Limed fields, driveways, and roadways with limestone rock decrease the pH levels making the water body more basic highly toxic to fish.

Now see what happens after the grass has time to absorb the fertilizer before it "rains"

NOTE: Use the piece of sod that has had the fertilizer overnight, a thoroughly rinsed mesh and a new liner.

6.     Measure 250 mls of tap water and pour it SLOWLY on the piece of sod making sure to COVER THE WHOLE AREA.

7.     Conduct the phosphorous/nitrogen/ pH tests again (Depends on what tests are available)

PHOSPHOROUS

NITRATE

NITRITE

AMMONIA

For the complete runoff experiment visit:

https://KansasRiverScience.org/whats-water/nutrients/runoff-lesson

** Some materials have been taken from the Friends of the Kaw Websites:

Nitrogen, Phosphorous , Runoff Experiment **

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