Simplify the following text for a Grade 9 native English-speaking person.
Original: The Onyx River is a meltwater stream which flows eastward through the Wright Valley from Wright Lower Glacier and Lake Brownworth at the foot of the glacier to Lake Vanda , during a few months of the Antarctic summer .
Simplified: The Onyx River is a meltwater stream that flows to the west through the Wright Valley between the Wright Lower Glacier to Lake Vanda .