Endovalley Road to the Alluvial Fan from highway 34 is a two way road and you can backtrack to highway 34 after visiting the Alluvial Fan. It is a google maps error that indicates you must travel Old Fall River Road to get back to highway 34. We actually discussed this on the TA Rocky Mountain National Park travel forum back in early November when you were planning this trip. If you want to look back, click on your screen name and all your posts on TA will come up.

If you enter the Fall River Entrance to RMNP, the Alluvial Fan is about 3 miles from this entrance. You will see the right hand turn off highway 34 onto Endovalley Road. There is a sign. You can download the official RMNP map on the park's website. You will see the Alluvial Fan on the map.

It's a short drive back to Estes Park, passing the Fall River Visitor Center on your way.

That depends on what you mean by accessible. The paved trails that led from the east and west parking lots to the waterfall are no longer there. The road has been repaired. While some of the flood debris between the road and what remains of the waterfall has been removed, the footing through this area is tricky as you must maneuver around downed tree trunks and rocks and boulders. The footing on the south side of the road (not the waterfall side) is a little better. If you saw this area before the September 2013 flood, the change is very dramatic and not for the better. For those of us who have such great memories of the Alluvial Fan before, it is hard to appreciate it as much now.