(5) http://en.wikipedia.org/wiki/File:Obvious_water_pollution.jpeg. CC-BY
2.5.(6) USACE.http://en.wikipedia.org/wiki/File:Atchafalaya_Basin.jpg. Public
Domain.(7) http://commons.wikimedia.org/wiki/File:Macquarie_perch.jpg. GNU-FDL.(8) http://en.wikipedia.org/wiki/Image:Poland_Solina_dam.jpg. GNU-FDL.(9) USACE.http://commons.wikimedia.org/wiki/File:Great_Lakes_1.PNG. Public
Domain.(10) http://en.wikipedia.org/wiki/Image:Bragan%C3%A7a43.jpg. CC-BY-SA 2.5.
(11) http://en.wikipedia.org/wiki/Image:
Iceberg_with_hole_near_sanderson_hope_2007-07-28_2.jpg. GNU FDL.
(12) Lollie-Pop.
http://en.wikipedia.org/wiki/File:Sheep_and_cow_in_South_Africa.jpg.
CC-BY 2.0.
(13) Dan Swenson.[pathsoflight.us/musing/?m=200710 ]. GNU-FDL.
(14) USACE.http://en.wikipedia.org/wiki/File:Atchafalaya_Basin.jpg. Public
Domain.
(15) EPA. Municipal and agricultural pollution.. Public Domain.
(16) USCG.http://en.wikipedia.org/wiki/File:Ship_pumping_ballast_water.jpg.
Public Domain.
(17) http://en.wikipedia.org/wiki/File:
Nrborderborderentrythreecolorsmay05-1-.JPG. Public Domain.
(18) Emily Hayflick.. CC-BY-SA.
(19) http://en.wikipedia.org/wiki/File:
Research-_water_sampling_equipment.jpg. GNU-FDL.
(20) USAF.http://en.wikipedia.org/wiki/File:
Humanitarian_aid_OCPA-2005-10-28-090517a.jpg. Public Domain.
(21) http://en.wikipedia.org/wiki/File:Drought.jpg. GNU-FDL.
(22) http://en.wikipedia.org/wiki/Image:Crystal_Lake.jpg. GNU-FDL.
(23) [www.who.int/water_sanitation_health/dwq/gdwq05061.pdf ]. Public Domain.