1. Team Members Siow Zi Hao (Group Leader) 1A2 Regan Tan 1A2 Ravn Teo 1A2 Richie Chua 1A2 Group ID: 1004

4.  A rain garden is a shallow depression that is usually positioned near ad own slope of a runoff source like a downspout, driveway, sump pump or roof.  This areas can encounter pollutants like oil, soil fertilisers, soap, pipe waste and sediments along its way to drains.  So a rain garden is need to protect water quality

5.  A rain garden protects water quality by collecting runoff from these impervious areas.  Rain gardens are a cause effect of way to manage rainwater as it prevent pollutants and excessive amount of runoff water from reaching streams, lakes and other water way  It also reduces downstream flooding, increase ground water recharge, help sustain base water flow of streams

6.  A rain gardens can also add beauty to landscape and provide wildlife habitat.  Due to its shallow depression, a rain garden can absorb rainwater runoff.  This also prevents rainwater from encountering pollutants and at the same time, filter pollutants which are in the water

7.  A rain garden have level bottom to allow rain water to spread across entire surface,  This also allows rainwater to slow down and soak in so that it can be filter by the plants and soil within the rain gardens.

10. Gravel Soil made of manly sandy soil Filtration layer Water recharge zone

12. The Objective of our experiment To find out which soil is retains the least amount of water Hypothesis of our experiment Sandy soil retains the least amount of water.

13. 3 Soils: clay, humus, sandy 16 – 1.5 litres coke bottles 1 measuring cylinder 1 stopwatch 3 beakers 1 laboratory thermometer 10 filter cloth (tap filters) 1 retort stand 1 tripod stand

14. Level at which soil is filled up to Soil Coke bottle Mouth of bottle covered with filter cloth \ Retort stand to hold coke bottle Beaker where water will be poured from Filter funnel Beaker for collection of water 28 degrees Celsius (Air-conditioner on)

15. Level at which soil is filled up to Soil Coke bottle Mouth of bottle covered with filter cloth \ Retort stand to hold coke bottle Beaker where water will be poured from Filter funnel Beaker for collection of water 28 degrees celcius (Air-conditioner on)

17. Independent variable: Type of soil Dependent variable: Amount of water that will pass through soil Controlled variables: Size of hole in the container containing soil Amount of water poured Amount of soil Size of containers Duration of experiment

18. 1.Firstly, label 3 - 1.5 Coke bottles with A, B and C. 2.Next, fill A, B and C with sandy soil, clayey soil and humus soil respectively 3.Pour 200 ml of water through the bottom of the A 4.Start the stopwatch at the same time. 5.Stop after 2 minutes and record the amount of water in the beaker 6.Repeat steps 3-5 two more times for A and 3 times each for B and C.

19. Sandy Clayey Humus Control 150 ml ( all the water flowed through before 2 minutes) Reading 1Reading 2Reading 3 Average 80.0ml 79.0ml 81.0ml 80.0ml 62.0ml 60.0ml 59.0ml 60.5ml 38.0ml 33.0ml 35.0ml 35.5ml Std deviation 1.00 1.53 2.52 std error 0.58 0.88 1.46

20. 1 st attempt 3 rd attempt 30 ml 40ml 50ml 60ml 70ml 80ml 90ml LEGEND - Humus - Clayey soil - Sandy soil average 38ml 33ml35ml 35.5ml 62ml 79ml 59ml 60.5ml 80ml 60ml 81ml 80ml 20 ml 10 ml 0 100ml 140ml 120ml 130ml 150ml 110ml 2 nd attempt - Control 150ml

21. Sandy Clayey Humus Control 150 ml ( all the water flowed through before 2 minutes) Reading 1Reading 2Reading 3 Average 80.0ml 79.0ml 81.0ml 80.0ml 62.0ml 60.0ml 59.0ml 60.5ml 38.0ml 33.0ml 35.0ml 35.5ml Std deviation 1.00 1.53 2.52 std error 0.58 0.88 1.46

22. 1 st attempt 3 rd attempt 30 ml 40ml 50ml 60ml 70ml 80ml 90ml LEGEND - Humus - Clayey soil - Sandy soil average 38ml 33ml35ml 35.5ml 62ml 79ml 59ml 60.5ml 80ml 60ml 81ml 80ml 20 ml 10 ml 0 100ml 140ml 120ml 130ml 150ml 110ml 2 nd attempt - Control 150ml

23. The temperature of the surroundings (Science Lab) The humidity of the room Angle at which the water is being poured Temperature of soil Exact same rate at which water is poured

26. From our experiment, we found out that water flows through Sandy soil at the highest rate as compared to the other soil types. Therefore, Sandy soil should be used at a greatest amount than humus and clayey soil for the building of a rain garden. Sandy soil is not used used only as there is hardly any water and nutrients in the soil, thus plants will not grow well.

27. A little clayey soil is needed so the plants would not behave as if they were in a clay-bottomed pot and stay at the top layer soil and as a result, water would not move through the soil as fast as it should be. A bit of humus is needed to provide some nutrients for the plants as sandy soil hardly contain any nutrients. Although this 2 soils retain a lot of water, the rate of infiltration will not be greatly affected.

31. http://nricd.org/Lesson_7_Experiment.pdf http://www.wisegeek.com/what-is-soil-drainage.htm http://www.for-wild.org/download/rainclay/rainclay.html http://organicgardening.about.com/od/soil/a/improveclaysoil.h tm http://www.rain.org/global-garden/soil-types-and-testing.htm http://ag.arizona.edu/turf/tips1095.html http://www.funsci.com/fun3_en/exper1/exper1.htm http://school.discoveryeducation.com/schooladventures/soil/n ame_soil.html http://school.discoveryeducation.com/schooladventures/soil/n ame_soil.html