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(a) Describe how a river capture occurs
(b) Give two reasons as to why Lake Naivasha is a fresh water lake

Answer Text:
a) -Two rivers adjacent to each other share a common divide
-One river is more powerful than the other due to high volume of water from a pirate river.
-The pirate river erodes vertically and laterally faster than the weaker river.
-The valley of the pirate river becomes deeper and wider so as the river flows at a lower level than the weaker river.
-The stronger river extends its valley backwards by head ward erosion
-Eventually the pirate river joins the valley of the weaker river.
-The head wards of the weaker river are diverted into the
stronger river hence a river capture occurs
b) -Has underground drainage
-Rivers from its surrounding have fresh water which dilutes the salts