The water comes from 3 different sources near the top of the water feature. They're a little tricky to find. I didn't even realize my guys had built the 3rd one (on the left side of the photo below) until 3-4 weeks after we finished the water feature. They did a good job of hiding the source of the water. There are two biofalls units hidden near the top of the water feature and one big rock bubbler over to the right. Water comes from these three sources (marked in blue) and trickles down the water feature from each of these points.