I just cleaned mine today. It was packed with dirt!!
Jack passenger side up
Take passenger front wheel off
Remove the inner front fender liner. You only have to remove the rear part of the liner.
The drain is black and shaped like a triangle. 2 10mm bolts and out it comes.
Wash out the inside of the drain vent. Can also pour some water very carefully down past the windshield wiper tank from the hood to help flush any dirt or debris out. Careful not to splash any water on the battery.