watershed

1. --- major watershed --- smaller watershed watershed • what is a watershed? The land area that water moves across or under, while flowing to a stream, spring, pond, lake or river The area of land where all of the water that is under it or drains off of it goes into the same place

2. medium importance of watershed understanding watershed human body

3. importance of watershed understanding watershed human body pollution/ catastrophe diseases/injury health problems

4. field study examination investigation importance of watershed understanding watershed human body

5. chemical, biological,… tests medical analysis tests importance of watershed understanding watershed human body

6. importance of watershed understanding watershed human body remediation, law enforcement, better management, … medication/surgery diagnostic and action

7. water input input increases the amount of water in the watershed rain groundwater output decreases the amount of water in the watershed watershed water output watershed outlet, domestic, agriculture, and industrial use transpiration, evaporation… importance of watershed understanding amount of water available today = amount of water available yesterday + water input between today and yesterday - water output between today a yesterday WATER BALANCE WATER BALANCE: make sure that the mount of water available tomorrow will not be too low allows a good management of the watershed and long term water supply equilibrium means OUTPUT=INPUT

8. Why? Where is the pollution source? watershed importance of watershed understanding • Understanding the watershed also means: • understanding where the water is, • how the different water bodies are inter-connected, • in which direction water flows in the watershed • Important to help identify pollution sources

9. wateshed • what is a river? a river is surface water, it is where the water table is higher than the ground. It then follows gravity source tributary runoff runoff main river infiltration water table groundwater recharge discharge

10. watershed • what is a lake? a lake is surface water that accumulates in a low point

11. distance duration (hours) surface velocity of water = distance / duration mean velocity of water ~ 0.8 x velocity measuring discharge river

12. cross-section area = number of x area of measuring discharge accurate discharge measure is tricky also, discharge changes with… position along the river… why? time… why? discharge = area x mean water velocity

13. L 1-2 L 2-3 L 3-4 L 4-5 1 2 3 4 5 A1 A2 A3 A4 L 4-5 A5 L 3-4 L 1-2 L 2-3 measuring volume

14. find maps and use them • look at mountains, sea • look at the topography • where will you find the maps? watershed • what is a watershed? we all live in a watershed! • where is yours? • what is its size? • where is your water (rivers, streams, lakes) ? • how does it flow? draw a map of your watershed

15. water source team • where are the rivers and streams in your area? • what names do your rivers have? • how large are they? • where do they come from? • how would you measure their stream-discharge? • how much water do they have at any time? complete your map

16. water source team • is there a lake in your area? • what type of water? • what size, how deep? • which rivers are connected to the lake? • how old is it? how has it been created? • how much water does it have? When? name the lake on your map

17. groundwater and runoff • what is groundwater and runoff? permeable underground runoff soil surface ground water=aquifer impervious rock

18. underground structures soil layer 1 layer 2 bedrock impervious rock (granite, clay)

19. groundwater and runoff Permeability measures how fast water flows in the rock. The flow-rate is proportional to the permeability A=pr2 h permeability pressure P = r g h gravity L water density water viscosity

20. groundwater and runoff A=pr2 - - h0 h(t) - P + - - L - 1 Darcy = 10-12 m2

21. porosity= volume of water in the sample volume of the sample water saturates groundwater and runoff water tank Permeability measures how fast water flows in the rock. The flow-rate is proportional to the permeability rock sample

22. K permeability analysis of experimental (falling head) data K is the velocity of water under gravity

23. water-table depth depth of aquifer bottom groundwater soil layer 1 layer 2 bedrock impervious rock (granite, clay) unconfined aquifer

24. water-table depth depth of aquifer bottom groundwater soil layer 1 layer 2 bedrock impervious rock (granite, clay) confined aquifer

25. groundwater and stream soil unsaturated zone water table saturated zone surface water impervious rock grains making up the rock pore space partially saturated water-table pore space saturated

26. aquifer loosing aquifer gaining perched aquifer aquifer-stream connections

27. runoff plants are obstacles: slow down water plants limit water impact plants roots hold soil in position

28. soil erodes sediment transported to nearby stream desertification: plant cannot grow back groundwater and runoff deforestation can trigger soil erosion, sediment pollution and desertification

29. runoff runoff runoff angle angle lower runoff higher runoff the larger the angle, the faster the runoff the fast the runoff, the larger the erosion force velocity is proportional to sin(angle) force is proportional to velocity

30. water source team • what is groundwater and runoff? • what parameters affects surface runoff? • how important is runoff in your area? • where can you measure the water-table? • when should you measure it? • how deep is your aquifer? • how could estimate its volume? complete your map

31. wind precipitation evaporation rain runoff transpiration runoff infiltration runoff discharge infiltration discharge

32. rain March August September it varies with season runoff varies with seasons filtration varies season river level and discharge vary with season

33. intensity = rainfall amount rainfall duration duration (hours) amount (mm) rain • measuring rain ruler

34. water source team • how is rain on your watershed? • rainfall amount • rainfall intensity • rainfall duration • rainfall distribution • rainfall frequency complete your map

35. water source team • what would you measure to perform a water balance? • rain amount? • consumption? • aquifer volumes? • river volumes? • …?

36. point source pollution point source pollution initial extent of pollution transport final extent of pollution dispersion initial extent of pollution final extent of pollution transport dispersion pollution transport and dispersion

37. non-point source pollution runoff pollution transport and dispersion

38. use and pollution • how does your community use your watershed! • where are the houses? • how can they affect water quality? • where are the farms? • how can they affect water quality? • where are the industries? • how can they affect water quality? • where are the embankments? • how can they affect water quality? • where are the wells? complete the map of your watershed

39. Thailand News December 5th 1997 500,000 fishes dead, enormous numbers of dead shellfishes and aquatic fauna Nongboanoi village, Nam Phong river, Khon Kaen province Hg j gj g jg jg kihik ho u kh kg uf jh loh kg kg iy I gbkjgbjgfj tgj gj gj gt hk hg kh kh k hk y kg kjy kh hi yk h ,jh lk h hk hk hk h kj ;l ;p I;p oi; I [ppo ‘;k ;k k; k; k ;l ;k ;ip uipuilkhk h hk hk h hkhkhk kj khkh kjh kj hkjhkh iu gtf re t jlk jp; kuhjyghfdtyd lk kg jyfgj b li lj lj Hg j gj g jg jg kihik ho u kh kg uf jh loh kg kg iy I gbkjgbjgfj tgj gj gj gt hk hg kh kh k hk y kg kjy kh k hi yk h ,jh lk h hk hk hk h kj ;l ;p I;p oi; I I [ppo ‘;k ;k k; k; k ;l ;k hk hk h kj ;l ;p I;p oi; I I [ppo ‘;k ;k k; k; k ;l kg iy I gbkjgbjgfj tgj gj gj gt hk hg kh kh k hk y kg kjy kh hi yk h ,jh lk h hk hk hk h kj ;l ;p I;p oi; I [ppo ‘;k ;k k; k; k ;l ;k ;ip uipuilkhk h hk hk h hkhkhk kj khkh kjh kj hkjhkh iu gtf re t jlk jp; kuhjyghfdtyd lk kg jyfgj b li lj lj Hg j gj g jg jg kihik ho u kh kg uf jh loh kg kg iy I gbkjgbjgfj tgj gj gj gt hk hg kh kh k hk y kg kjy kh k hi yk h ,jh lk h hk hk hk h kj ;l ;p I;p oi; I I [ppo ‘;k ;k k; k; k ;l ;k hk hk h kj ;l ;p I;p oi; I I [ppo ‘;k ;k k; k; k ;l example why?

40. Khon Kaen province Nam Phong river Ubolratana dam Nongboanoi village Chot stream Upper Mae Nam Chin basin 1st step • where is it? find a map, locate village and river

41. Pulp and paper factory! Nam Phong river Ubolratana dam wood, bamboo Nongboanoi village Chot stream pulp, paper, organic wastes 2nd step • ask the locals: what do you think, what do you know?

42. 1 upstream suspected stream Nam Phong river 1 2 downstream suspected stream Ubolratana dam 2 3 downstream suspected source 3 Nongboanoi village 4 upstream suspected source Chot stream 4 3rd step • prepare testing strategy: what to measure and where? choose sampling stations

43. organic material Nam Phong river Ubolratana dam oxidised bacterial activity decay (tannin/lignin) Nongboanoi village Chot stream COD tannin BOD, DO 3rd step • prepare testing strategy: what to measure and where? choose what to measure 1 2 3 4

44. tannin COD DO ? 51 4 Nam Phong river Ubolratana dam 0.57 424 3.55-3.75 O.77-15.95 140-664 ? Nongboanoi village Chot stream 0.19 72 ? 4th step • analysing the result? results (mg/l) 1 1 2 2 3 3 4 4

45. conclusion? Nam Phong river Ubolratana dam Nongboanoi village Chot stream 5th step Where does pollution come from? How to improve the investigation? 1 What could make the investigation more difficult? 2 3 4