Here’s a nice view of the nearly-completed New Croton Dam (also known as the Cornell Dam) circa 1907. We can roughly date the image from the state of construction and the card itself because it’s an “undivided back” postcard, issued during the period from 1901 to 1907. Until 1907 only the mailing address could be written on the back of the card.
This card was published by William Terhune in “Ossining on Hudson” and printed in Germany.
Here are some other Terhune postcards:
CROTON 
These photos are 116 years old of today,
May 6, 2023.
I see that there is a stair way that leads to the dam river.
A couple of years ago, I went to the Croton Dam with my family and we walked down to the stream with my nieces and nephews as toddlers.
I think this is a very touristed park 🏞️.
The steps in 1907 should be put engineered in place for better access to the stream.
Multiple stairs ways should be engineered to lead to the stream.