Culvert Restoration

SW Portland, Oregon

One of our flagship projects: A true depiction of our dedication to doing what it takes to restore our ecosystems and making them accesible to future generations, even if it means working in deep ravines, carefully placing 45 tons of rock with no machines, and starting from the very beginning with immense overgrowth of invasive species.

The view down into this creek was invisible on my first visit. There was nothing to see but immense bramble - a mixture of invasive holly, ivy, blackberry, english hawthorne, and plum. It was so thick and impenetrable, we didn’t even touch it for a year, instead focusing on the more accessible parts of the yard.

The pictures in this page will show the whole story, somewhat out of order, achieved in a series of steps over a number of years. Our first visit was in 2019, and we’ve come a long way since then.

From a steep slope, we carved a path in, armored it with stone, and made a plateau to gaze at the water incoming from the underroad culvert. No ecosystem can be maintained without proper access in and out. An inviting patio, gaining patina with age, invites timeless interaction with the previously untouched garden.

In service to the waters, and honoring its intense power, we were faced with tough decisions for how to protect the land from washing away. With a house perched above the steep eroding slope, and old red alders reaching their period senescense, we armored the (more than) vertically eroded banks with stone, creating a smooth angle of repose, and in many cases built the armor into stone stairways.

Our work on the banks of the creek allowed us to create beaver dam analogue structures to slow the flow and retain the waters higher in the watershed.

Extreme erosion undercutting the roots of scenescing alders.

The culvert fills up 100% during early season extreme rain events, and previously scoured out the bowl, and undercut the banks.

Stone armor doublefunctioning as a stairway for access to the creek.

The stairs make for a great place to sit and enjoy the flow of the creek.

Kyle Schwartz standing proud above our multi-functional stairs and bank armor, which provide a comfortable crossing from one side of the creek to the other.

More than vertical erosion reaching almost 10 feet of sheer face here, just below a major roadway, necessitated the use of many tons of stone.

A view back toward the culvert and the yet unfinished “bowl” with steep eroded banks.

Though somewhat channelized (not our ideal), the gaps between stones provide immense habitat opportunity, and fill with organic matter. Water velocity is managed with the use of “one rock dams,” while also allowing for heavy storm events to proceed through the property without causing any damage whatsoever.

Daniel Newman proud of our “Phase 3” of rock armor, further down slope from the culvert, where previously vertical 6 foot eroded walls sat just below the home structure above.

2 years after our initial installation of stone and other restoration work, our critter observations started to pop off! Here a crawdad discovered by Daniel Newman.

Cute salamanders were carefully reintroduced into a safer place in the landscape after their discovery.

These videos demonstrate the power of this creek during heavy storm events. Note the video at night where the culvert is 100% full, and water is flowing over the surface of the soil from the road above. This type of power eroding the slopes below a home is what necessitated the use of stone, rather than a more organic approach, such as relin-stream wood and plants.

Eventually the alder’s decline progressed to the point of requiring pollarding, retaining fantastic towers of snagged trunks. The wood was integrated into the landscape for slope retention, pathway definition, and mushroom cultivation. We inoculated shiitake and oyster mushrooms into branches and towers, and integrate King Stropharia spawn into the woodchips spread everywhere, resulting in some fantastic fungal displays. Plants found their homes amongst the slopes, with more being added each year.

Peter Condra from Columbia Land Trust and Green Lents joined us and helped clear the space we lovingly now know as “Peter’s Plateau.”

“Peter’s Plateau”

In year three, we progressed to the “bowl,” closer to the culvert, still shrouded in ivy and forsythia. Here we found more steep eroded slopes, but opted to manage this area with cardboard, coco-coir erosion control fabric, and a woven net of branches. We created a series of terraces and planting nooks, which we filled with a beautiful set of Western Native plant species.

Another section of the property was still utterly inaccessable, steep and overrun with ivy, holly, & hawthorne. The neighbor’s property occasionally flooded over onto the slope, so we needed to think fast for how to manage excessive water on a steep slope, while enhancing access and maintaing planting space. We integrated a series of rain catchment basins filled with drain rock and french drains, allowing us to catch and maintain moisture in the hill while draining off the excess so as to not hyper-saturate the steep west side slopes that are prone to landslides. We installed retaining walls with a sloping aspect to allow for future planting in the cracks, and worked in a stairway

Our original work in the front upper slopes of the property was done prior to all the creek work, and eventually we had a fantastic tapestry of drought tolerant Western Native species with high contrast and fantastic textural displays.

OR LCB #9872; WA# Earthel843J2

858.774.7900