This private residence is a three-acre landscape design and
restoration project overlooking the scenic Columbia River
Gorge near The Dalles, Oregon. Riverside sandy soils overlay
massive formations of bedrock that are at times exposed and
more typically lie 6 to 30 inches below the surface. Shallow
basalt bedrock prevents infiltration causing some areas to
be easily saturated and quickly parched. These site-specific
conditions create a variety of planting conditions that rely
heavily on the adaptability of regional species.
Climate conditions are equally varied. Frigid winters with
temperatures near 0 degrees Fahrenheit and summers with sustained
temperatures between 90 and 110 degrees Fahrenheit and limited
rainfall reduce the survival rate of plants other than native
species that have evolved in the area.
Fluctuating river flows bring invasive plant species from
up-stream urbanized locations, as do seasonally strong winds
and migrating Canadian Geese that visit the site. <
Neighboring properties also harbor non-native invasive species
that require vigilance to control. A seasonal regimen of site
reconnaissance was instituted to combat non-native and invasive
plant species including grass species that are very difficult
to selectively eradicate.
The purpose of the project was to provide the clients, whose
primary residence is in Seattle, Washington, with a landscape
that demonstrates stewardship toward the native landscape
and minimizes the visual intrusion of a new home in the Columbia
River Gorge Scenic Corridor, guest house and windsurfing board
shed on the shores of the Columbia River. This goal was consistent
with the philosophy of the landscape architect and the architect
whose buildings respect the natural site by mitigating environmental
and visual impact by accentuating the dramatic nature of a
site. The vertical profile of the buildings was reduced by
being partially buried below grade. The guesthouse and windsurfing
board shed were designed with green roofs that mitigate their
visual intrusion and provide insulation. Low maintenance was
also a motivating factor for the clients who feel the natural
landscape is the most effective strategy to reduce energy
consumption and maintenance.
The clients, whose recreational focus is windsurfing, also
enjoy entertaining guests and neighbors. They believe their
landscape is a ‘seed’ project that may influence
aesthetic tastes and land stewardship in contrast with landscapes
that require intensive energy and resources to maintain in
this region.
Milestone Nursery in Lyle, Washington just across the river
was contracted to hand collect seed of native plants and grow
them for this project. Plants that are native but too rare
to be found for seed collection were imported from Natures
Enhancement, Inc in Stevensville, Montana. Rainier Seed Company
supplied native grasses. Native sagebrush was transplanted
from overgrazed and disturbed sites and now flourishes in
its new home.
The role of the landscape architect was to design and coordinate
the construction of a landscape that enhances and restores
the site’s natural characteristics and re-establishes
its relationship to the regional landscape. Views within the
site and to the dramatic context are framed by naturalistic
plantings from multiple positions giving the landscape a unique
visual dynamic. The modulation of the native landscape included:
removal of invasive species, the use of contract grown native
and rare species, revealing and re-creating bedrock outcrops,
native plantings, drip irrigation, and sustainable methods
of maintenance.
The landscape design subtly integrates local landscape forms
into the functional aspects of the site. The flat plain of
the decomposed granite terrace mimics the early morning currents
of the river and accentuates the calming feel. The minimalistic
solemnity of the terrace also provides a relaxing contrast
to the white capped wave action of the summer afternoons.
Separation and screening is accomplished by modest landforms
and selection of native plant types. The entry to the site
was choreographed to eliminate the presence of cars in the
main landscape area and living areas while providing convenient
drop off points. Orientation of the garage and the design
of the road were coordinated with the architects. An active
play area was developed in front of the guesthouse over the
existing septic system. A riverside terrace created for relaxation
and entertainment was constructed with decomposed granite
and contained by natural and recreated bedrock outcroppings.
Informal paths approach the feel of trails and are routed
through planting areas to the various buildings and lead
visitor to framed views. This project exceeded the client’s
expectations to build with the landscape and to exhibit stewardship
to nature and the Columbia River Gorge Scenic Area.
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