Being part of Wailua River State Park helps. Trails to ‘Opaeka’a Falls are generally maintained and signed, and the park is the first place to check for closures before you go.
It is also one of the few falls we can link to a live USGS stream gauge, so you can check how much water is coming down before you leave home.
The draw here is the moment the sound reaches you before the water does. People plan whole days around falls like ‘Opaeka’a Falls: a walk through the woods, cold spray at the base, and a quiet spot to sit for a while.
Geology and background
What makes ʻŌpaekaʻa Falls special
ʻŌpaekaʻa Falls is a 151-foot waterfall on the ʻŌpaekaʻa Stream in Wailua River State Park, on the eastern side of Kauai. It flows over basalt laid down by volcanic eruptions millions of years ago, and the rock itself is part of the view: below the ridge, down into the ravine, you can see the vertical dikes of basalt cutting through the horizontal Koloa lava flows.
The name is the story. ʻŌpaekaʻa means rolling shrimp: ʻopae is Hawaiian for shrimp, and kaʻa for rolling. It dates back to days when the native freshwater shrimp Atyoida bisulcata were plentiful in the stream and were seen rolling and tumbling down the falls and into the churning waters at the base. The name remembers a time when the stream was full of shrimp; the fall keeps the name even as the shrimp have thinned.
Its neighbours are close. Uluwehi Falls is 0.7 miles away, Kaholalele Falls 2.1 miles away and Hoʻopiʻi Falls 4.2 miles away, so the Wailua River valley holds several falls within a short drive of each other.
The fall drops over basalt from volcanic eruptions millions of years ago. The geology is visible in the ravine walls: vertical dikes of basalt cut through the horizontal Koloa lava flows, a cross-section of how the island was built, layer by layer and intrusion by intrusion.
Navigate by coordinates rather than by name. Map apps often send waterfall searches to the wrong parking lot or the far side of the stream. Download an offline map before you lose signal.
Best time and crowds
This is a rain-fed island fall, so flow follows the weather. A stream gauge is linked on this page: check the live flow before you go. Expect the most water after heavy rain, and the least in a dry spell.
Kauai’s east side draws visitors year-round. Arrive early or late: the middle of the day is peak time, and the small roadside pullouts can be full by late morning.
Safety
Stay on marked trails and behind railings. Wet, mossy rock near the brink is the most common cause of serious injury. Never climb the cascade or stand at the top edge, even when the flow looks gentle. In canyons, rain upstream can raise the water in minutes: leave if the water turns muddy or starts to rise.
What to bring
Shoes with real grip
A rain shell for the spray and the island showers
Water and a snack
An offline map or screenshot
A dry bag for your phone
A bag to pack out trash
Practical tips
Check the live gauge before you go: rain-fed flow changes fast here.
Pair it with Uluwehi Falls, 0.7 miles away.
Screenshot the directions and these coordinates before you leave town.
Look for the basalt dikes in the ravine below the ridge: they are the clearest geology on the page.
A waterfall is a stream caught in the middle of reshaping its valley. The plunge pool at the base is scoured out by falling water and the stones it carries, and the lip retreats a little with every flood.
Water flow and seasons
The stream that feeds ‘Opaeka’a Falls is tracked by USGS gauge 16060000. A reading well above the seasonal median means a fuller fall, and usually a wetter, muddier trail.
Expect the most water in spring and after heavy rain. In a dry spell, especially late summer and early fall, the same fall can look half the size.
We do not have a trail length for ‘Opaeka’a Falls yet. Some falls are a few steps from a parking area, others take a real hike, so check the park or a trail app before you set out.
Swimming is not listed. Treat the plunge pool as off-limits unless signs say otherwise: the water at the base is colder and stronger than it looks.
Facilities and amenities
Facilities depend on Wailua River State Park: larger parks usually have a signed trailhead, restrooms and a parking area, while smaller reserves may have none of these.
Plan as if there is no drinking water and no phone signal at the falls themselves. Use the restroom and fill your bottles before you start walking.
Fees, permits, and opening hours
No entry fee is listed. Parks may still charge for parking or day use, and federal lands often accept an annual pass instead.
Most falls are reachable from dawn to dusk. Gates, seasonal road closures and timed-entry permits are the usual surprises, so check the managing agency on the day.
How to get to ‘Opaeka’a Falls
‘Opaeka’a Falls is in Wailua River State Park, Hawaii. For the last stretch, navigate by coordinates (22.04821, -159.36201) rather than by name. Map apps often send waterfall searches to the wrong parking lot or the far side of the stream.
The final approach is usually the hardest part: narrow roads, small trailhead lots that fill early, and a walk that can be ten minutes or several hours. Download an offline map before you lose signal.
Our Hawaii waterfalls page maps every fall in the state, which helps when you are planning a route.
For the fullest flow, visit ‘Opaeka’a Falls in spring or within a couple of days of heavy rain. For easier footing and warmer air, early summer is the compromise.
Light matters for photos: the base of a fall is often in shade by midday, and an overcast day evens out the bright water against dark rock.
Crowds and timing
Arrive early or late. The middle of a summer weekend is peak time almost everywhere, and small trailheads can be full by 10 a.m.
Holiday weekends and the first warm days of spring are the busiest of all. If the lot is full, do not park on the road shoulder: it is the most common reason for tickets and towing at trailheads.
How long to spend there
Without a listed trail length, plan for half a day: enough time to find the trailhead, walk in, spend an hour at the water and walk out without rushing.
If there are other falls nearby, they are often on the same road or trail system. Two or three in a day is very doable.
Where to stay near ‘Opaeka’a Falls
We do not recommend specific places to stay. The links below search for hotels and campgrounds around ‘Opaeka’a Falls on Google Maps, so you can compare drive times from the trailhead.
Stay on marked trails and behind railings. Wet, mossy rock near the brink is the most common cause of serious injury.
Never climb the cascade or stand at the top edge, even when the flow looks gentle.
Plunge pools hide cold water, strong currents and submerged logs. Only swim where it is allowed.
In canyons, rain upstream can raise the water in minutes. Leave if the water turns muddy or starts to rise.
Leave no trace: pack out trash, stay off fragile moss and plants, and keep drones grounded where they are banned.
What to bring
Shoes with real grip
A rain shell for the spray
Water and a snack
An offline map or screenshot
A dry bag for your phone
Cash for parking
A bag to pack out trash
Practical visitor tips
Screenshot the directions and these coordinates before you leave town.
Wear shoes you do not mind getting wet: spray reaches further than you expect.
Keep your phone in a zip bag near the base.
Pack out everything, including food scraps.
Tell someone where you are going if the trail is long or remote.
Frequently asked questions
Where is ‘Opaeka’a Falls, Hawaii located?
‘Opaeka’a Falls is in Wailua River State Park, Hawaii. Its GPS coordinates are 22.04821, -159.36201.
What kind of waterfall is ‘Opaeka’a Falls, Hawaii?
Its form (plunge, cascade, horsetail and so on) is not listed yet.
How tall is ‘Opaeka’a Falls?
Its height has not passed a source check yet, so we do not show a number or include it in tallest lists.
How much does it cost, and when is it open?
No fee is listed, though parking or day-use fees may apply. Most falls are open dawn to dusk; check the managing agency for seasonal closures.
Is ‘Opaeka’a Falls good for families?
It depends on the trail, which we have not confirmed. Check the length and terrain first, and keep children well back from wet rock and the edge.
How do I know if it is flowing?
Check USGS gauge 16060000 for today’s streamflow, and the last three days of rain in the weather panel.
The bottom line
‘Opaeka’a Falls is worth a detour, especially after rain. Go early, check recent rain, wear grippy shoes, and give yourself time to sit and listen once you get there.
Waterfalls nearby
One fall rarely fills a day. These are within about 40 miles.
Leave a waterfall report