Simplify the following text for a Grade 6 native English-speaking person.
Original: It travels roughly east to west , and several tributaries from the north and south join it as it flows to Big Tujunga Reservoir , formed by Big Tujunga Dam .
Simplified: It flows west to a reservoir called Big Tujunga Reservoir , formed by a dam at its west shore . After exiting the dam , the creek is known as `` Big Tujunga Wash '' .