The best time to visit is in wet season (May to October) as the water will be in full flow. We visited in November and dry season was already setting in - making it more of a "water-trickle". If you enjoy walking and being in nature, you'll still enjoy the walk.
Especially with small waterfalls, keep in mind that they look very different with long-exposure shots to short exposure. To get a good indication of what the actual waterfall looks like, check google maps reviews and see the photos that people have shared recently.
Wet season - long exposure photo, heavily edited picture
Dry season - standard phone picture
It may be a small challenge to find, but it's not a hard hike! Frm the main road to Prek Svay Waterfall is a 1km drive on a bumpy dirt road, then it's a 10-15 minute walk to a bathroom block and another 10-15 minute walk to the waterfall itself. The ground is uneven so make sure to wear comfortable shoes, but it is not steep.
***Disclaimer*** You will need a scooter or bike to get to Prev Svay Waterfall. You can hire bikes for as little as USD$8 per day from any rental places on the island, although if you are not a comfortable driver, ask your accommodation if they can organise a driver for you.
First, put Prek Svay Primary School into Google Maps and drive there. From most accommodations on the island, this drive will be on flat and paved road, so this shouldn't be too difficult to get to. Prek Svay Primary School is next to the Prek Svay temple/pagoda (វត្តគីរីជលសា) and should be hard to miss.
This map shows the four points to get to Prek Svay Waterfall. Google Maps is very inaccurate in Cambodia, so make sure to use satellite view to help you navigate.
The red circle is the turning point from Preaek Svay town (and the main road around the island) to Prek Svay waterfall.
The yellow circle is where you'll park your motorbike.
The blue circle is the toilet block and where the walk begins (offroad dirt bikes could get here, but it only takes 10 minutes to walk here and any automatic scooter would struggle).
The green circle is the waterfall itself.
Once you get to the Primary School, look towards the temple and you will notice a sign that says Prek Svay Waterfall and points to a gravel road. Follow this road. The path to the waterfall is well marked, so at each intersection have a look for signs and you'll easily be able to find your way to the waterfall. This drive should take 5-15 minutes, depending on how confident you are with riding.
You will see little hand painted signs like this the whole way that indicate the path to the waterfall.
This particular sign is the one that you'll see when you hit the carpark. It's not much of a "carpark", but it's where the trail stops and the ruts begin that aren't suitable for scooters. There may be another few bikes there. There's a barbed wire fence on the right (pictured) and a local's property on the left, with the trail directly ahead.
Walk for 10-15 minutes along the road until you get to the toilet block. It's not a hard walk but parts are rutted out and not great for scooters. Don't be that tourist who gets a scooter stuck, and just walk this part. 😉
From the carpark, it's around a ten minute walk to a toilet block with a bamboo shaded carpark area. When we got here, we noticed that there were two offroad dirt motorbikes here that had made the drive up to this part, but a scooter wouldn't make it up this road. It was only a ten minute walk, so if you're on a hire scooter, just stop at the carpark.
The toilet block isn't serviced and doesn't have paper or running water, so don't rely on it!
Th above photo is what the toilet block looks like it as you approach it. You can see there is a cream building (disused toilet block) and a bamboo structure (dirt-bike parking).
There is a footpath leading down to the left - do not take this one! It does not lead to the waterfall, but it is not marked.
Instead, walk under the bamboo structure then out the footpath at the end. This will take you right up the hill and past the toilet blocks.
Follow this path on, it curves around to the left a bit, and will put you on a dirt trail that looks like this. The walk to the waterfall from here should take on average 10-15 minutes.
You will hit a point that looks like this - as we went in dry season it's hard to see, but there is a small creek on the left side of the photo, and the footpath continues on the right. You can take either path to the waterfall - we went up the footpath and came back along the creek.
From here, you're only 3-5 minutes from the waterfall.
There are no facilities, and there are some snakes around. Where closed toed shoes and watch where you walk.
Be prepared, it's not a world class waterfall, so go with open expectations and just have fun. The waterfall is marked a few times on maps in different locations - if you look closely,
Wet season - long exposure photo, heavily edited picture
Dry season - standard phone picture