Water - Lakes, Reservoirs and Ponds

1. A lake is a landlocked body of naturally-occurring water that is quite large and deep.

2. The main sources of lake water are melting ice and snow, springs, rivers and rain

3. Natural lakes are usually found in mountainous or glacial areas.

4. Most lakes are freshwater and can be found in the northern hemisphere.

5. Lakes support a wide variety of flora and fauna.

6. Lakes in hot, dry regions tend to be salt lakes because of a high rate of evaporation.

7. Many of the lakes we see in the landscape today are man-made.

8. They have been created to provide water for homes and industry, for irrigation and for hydro-electric power.

9. Some of the lakes provide leisure facilities such as sailing, canoeing etc.

10. Man-made lakes are often made by diverting and damming rivers in locations where there are natural valleys.

11. A reservoir is a lake-like area where water is stored until it is needed and can be natural or man-made.

12. Man-made reservoirs are usually created by building a large dam out of earth, cement or rock and flooding the land behind it.

13. Reservoirs are used to provide drinking water to the surrounding area.

14. They can also be used for power generation and flood control.

15. Some reservoirs are turned into major tourist attractions, offering walking opportunities, fishing and water sports.

16. Dams are walls of earth, concrete or rock.

17. Dams are built to retain water and provide irrigation, control floods, supply water, improve navigation and provide electric power.

18. Dams can be made by humans, by natural causes, or by animals such as beavers.

19. They can be very high; some are over one hundred and fifty metres.

20. Dams can affect wildlife in the rivers.

21. They hold back debris such as leaves, branches and animal remains that organisms downstream depend upon.

22. Village ponds are common in Britain.

23. Many villages grew up around natural ponds because they provided a source of water.

24. Where there was neither a natural pond, nor a river, ponds were often dug and streams diverted to fill them.

25. Village ponds were used to provide drinking water for animals.

26. They were often stocked with fish to provide food for the villagers.

27. The water from the ponds was also used for fire-fighting.

28. Willows grew at the side of the ponds which were used for basket-making and thatching roofs .

29. Stagnant ponds and disused canals are great places for wildlife.

30. Certain types of fish and some frogs can be found in stagnant water.

31. It is the favourite breeding ground for a number of insects, including mosquitoes and dragonflies.

32. Stagnant water occurs when water stops flowing.

33. It can be a major environmental hazard.

34. It is especially dangerous for drinking since it contains many kinds of bacteria and other parasites.

35. Stagnant water may be identified by of its foul smell, and by the green algae that can be seen on its surface.