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Waterworks Garden

Puget Sound and Islands > Seattle-Tacoma Area
47.4716, -122.2424 Map & Directions
0.7 miles, roundtrip
Elevation Gain
30 feet
Highest Point
48 feet
Calculated Difficulty About Calculated Difficulty
Waterworks Garden. Photo by austineats. Full-size image
  • Dogs allowed on leash
  • Good for kids
  • Lakes

Parking Pass/Entry Fee


Waterworks Gardens is a public park managed by King County Parks. Complete with trails, art, native plants and wildlife this park winds visitors through a series of garden "rooms" of ponds, wetlands and marshes. Continue reading

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Hiking Waterworks Garden

This short walk provides a place to soothe your frayed urban nerves amidst a whimsical blend of natural artistry and urban water management. King County has double-purposed this eight-acre parcel to process stormwater runoff from an industrial water works plant, while also offering a mostly natural setting of ponds and wetlands for wildlife and low key human enjoyment.

The lands and rivers south of Lake Washington have been manipulated for the past 170 odd years. Coal mining, aviation, and other industries have flourished here. The landscape has been altered to to suit the people living here.

The Black River, which once drained the southern end of Lake Washington, is now a shadow of itself, only visible to those who look for it. In the general area of the confluence of the Black and the Green Rivers, near the inside crook of highways I-5 and I-405, sits the diminutive parcel of park known as Waterworks Garden. Adjacent to the north, although separated by a busy four-lane road, is the Black River Riparian Forest.

Walking into the gardens is like going to a naturalist’s theme park. The land is heavily manicured with large stone structures, water flowing through rivers into ponds and then draining through an intricate network of pipes down through a dozen or so other ponds before eventually draining into a quite natural wetland. There are good views here and there, as well as surprising little grotto corners, which invite sitting and relaxing.

The hum of Renton’s industry is never far off but the ease and subtlety of the gardens makes for a relaxing meander. Ducks frequent the ponds and many small songbirds have found homes here. The paved, circuitous trail is perfect for hikers of all abilities.

By starting at an area known as “the Knoll” one sees the gardens unfold from beginning to end. Once at the end you can either retrace your steps, or join the Springbrook trail to loop back towards your car through the aforementioned Black River Forest. Be very careful when crossing Oakesdale Ave SW on the way back to your car if you choose this loop option.

Access Note

Accessing the gardens is possible in a couple of spots but parking and traffic can be difficult. Parking for “the Knoll” is street parking on Monster Ave SW. Look closely at maps before trying to find this location.

Monster Ave SW and Oakesdale Ave SW merge where Monster Ave SW makes a ninety-degree turn southwards. At this point Monster goes from being a major connector road to being a short, dead-end access road to the King County South Treatment Plant. After turning onto this spur road the Knoll’s entrance is just a short distance on your left.

Hike Description Written by
Austin Smith, WTA Correspondent

Waterworks Garden

Map & Directions

Co-ordinates: 47.4716, -122.2424 Open in Google Maps

Before You Go

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Parking Pass/Entry Fee


WTA Pro Tip: Save a copy of our directions before you leave! App-based driving directions aren't always accurate and data connections may be unreliable as you drive to the trailhead.

Getting There

There are many routes to get to Waterworks Garden, and another direction may work better for you. These directions make for the fewest connections from an interstate.

From I-405, take exit number one (for State route 181 and Interurban Ave). Depending on whether you’ve come from the northbound or southbound lanes turn so you wind up on the NORTH side of 405. You want to turn east on to SW Grady Way. This road will be paralleling I-405 immediately north of the interstate.

Follow SW Grady Way for roughly three quarters of a mile. Turn left at a traffic signal onto the well-signed, Oaksdale Ave SW.

Follow Oaksdale Ave SW for about three quarters of a mile. It will bend ninety degrees to the left and then immediately become a divided highway with a median strip. The median strip only lasts a short distance. At it’s end is the junction with Monster Ave SW. Take a left hand turn onto Monster Ave SW at the end of the median strip.

The entrance to The Knoll and street parking is roughly two hundred (200) yards on the left. A fork in the road, which is gated, is on your left. This is where the walk begins. Do not block this forked road as it is access to the water treatment facility.

More Hike Details


Puget Sound and Islands > Seattle-Tacoma Area

King County Parks

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Waterworks Garden

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