The Getty Center and the Art of Erosion Control

The Getty Center, upper left, sits upon 110 acres of steep hills in the Santa Monica Mountains. Concrete culverts help to guide water runoff down the hills.

Atop 110 acres in the foothills of Southern California?EUR??,,????'???s Santa Monica Mountains sits a priceless art collection, viewed by millions every year. Also on this hilltop is an original and inventive use of a wide range of plants and horticultural techniques that will prevent wild fires and erosion.

The landscape at the Getty Center combines utility with pleasure, horticulture with aesthetics, and public and private space in a manner that is both unique and expressive. Within this context, landscape concepts and planting strategies also had to be conceived to solve a host of site development issues that range from installing planting and water features over structures housing priceless artwork and manuscripts, to re-vegetating land affected by development of the site.

While the art on top of the hill is meant to be reflected upon, a sculpted nail wall project is successful when the public doesn't even know it's there

Because of the Center?EUR??,,????'???s hillside setting, erosion is a concern, especially on the steep hillside that rises from the freeway below.

Located about one-half mile north of Sunset Blvd, the Getty Center looks down upon the bustling 405 freeway. The hillsides are steep that rise above the freeway, and are susceptible to erosion. The best way to combat this erosion issue was with sculpted nail walls. The hillside is not technically on the Getty Center property, so the task of fighting off erosion fell to the California Department of Transportation, also known as CalTrans. Engineers from CalTrans contacted Capistrano Beach, Calif.-based Boulderscape?EUR??,,????<

According to Steve Jimenez, Boulderscape?EUR??,,????'???s commercial division vice president, this sculpted nail wall has a bit of an artistic flair to it, possibly inspired by its proximity to the art museum. While the art on top of the hill is meant to be gazed upon and interpreted, a sculpted nail wall project is successful when the public doesn?EUR??,,????'???t even know it?EUR??,,????'???s there.

This 14,000 sq. ft. artificial rock formation is the facade of the slope's retaining wall and mimics the look of the natural rock of the surrounding hills.

?EUR??,,????'??We had to create a natural looking formation that exists in the surrounding mountains so that motorists and pedestrians don?EUR??,,????'???t notice it,?EUR??,,????'?? Jimenez said. He added that the 14,000-square-foot project took nearly three weeks to complete. It all started with a 4-foot by 4-foot mock up of what the proposed new hillside would look like. Inside the mock up was nearly six inches of shotcrete that resembled the sandstone on the hill.

From there, Caltrans architects viewed the mock up and approved it. Drill Tech, based in Antioch, Calif., did the drilling on the retaining wall that was installed. According to Mark Hood, Drill Tech?EUR??,,????'???s area manager in Southern California, this was a fairly average job, aside from the hard rock he was drilling into.

Planting strategies around the steep hillsides at the Getty Center had to be conceived to solve a host of site development issues. The hillside's ground layer has been planted with poverty weed, local chaparral and shrubs to ease erosion and slow the progress of brush fires.

?EUR??,,????'??This was a really clean job,?EUR??,,????'?? he said. ?EUR??,,????'??There was nothing too difficult, and that?EUR??,,????'???s the way you like it.?EUR??,,????'??

Hood estimates the wall stretches for nearly a half-mile along the 405 freeway and at its highest point climbs to 18 feet.

In order to get the walls attached to the hillside, Hood drilled soil nail anchors into the earth and then placed reinforced steel where the wall actually hangs.

?EUR??,,????'??We drilled the soil nail anchors into the hillside horizontally,?EUR??,,????'?? Hood said. ?EUR??,,????'??Those anchors are about six inches in diameter with a one inch steel bar in the middle. The area between the bar and the anchor is filled with cement grout.?EUR??,,????'??

The sculpted nail wall was installed and shotcrete applied to the facade. From there Boulderscape did horizontal and vertical stratification. Stratification occurs when a sediment?EUR??,,????'???s properties (usually texture) change with distance. It results when the energy level of the transporting agent changes with distance.

Rock outcroppings and ledges for a three-dimensional effect were added. That was allowed to cure for three-seven days and then staining artisans came in and applied the base stains, followed by a few highlight colors for shadowing. Darker colors were used for the sedimentary plane.

?EUR??,,????'??The finish-over product needed to blend with the existing surroundings so that motorists passing by wouldn?EUR??,,????'???t be distracted by the finish,?EUR??,,????'?? Jimenez said. ?EUR??,,????'??Several things had to be looked at before deciding on the type of formation sculpted and the color scheme used.?EUR??,,????'??

The artificial sculpted rock formation mimicked a natural rock formation north of the freeway.

?EUR??,,????'??It is logical to base the sculpted formation on a natural formation located on the same side of the freeway,?EUR??,,????'?? Jimenez said. ?EUR??,,????'??That way motorists traveling southbound will have seen the natural formation already. By the time they reach the sculpted wall they will see a formation seen previously.?EUR??,,????'??

The only change added to the sculpted wall was the use of inverted crevassing. The purpose of inverting the crevasses is to detour climbing enthusiasts and also to allow the water to sheet off the wall quicker and reduce the trapping of water.

Behind the wall, soil nail anchors were drilled horizontally into the hillside. The anchors are approximately six inches in diameter with a one inch steel bar inside of them to support the nail wall.

According to Jimenez, the development of the color scheme came by driving up and down the freeway several times to see what matched the natural rock. With a majority of the hillside covered with 90 percent darker vegetation such as dark greens and dark browns, the exposed sediment made up the other 10 percent.

?EUR??,,????'??We decided to blend the colors with the vegetation growing above,?EUR??,,????'?? Jimenez said. ?EUR??,,????'??We used a base color first, which was the lightest of all the colors. After the base color was applied, two additional colors were added to highlight rock outcroppings as well as add shadowing which gives the rock a more three-dimensional appearance.?EUR??,,????'??

Inverted crevassing was used on the sculpted wall to detour climbing enthusiasts and to allow the water to sheet off the wall quicker and reduce trapped water.

An anti-graffiti coating was applied to the wall as well.

Hood said the benefits of a nail wall include not having to cut away at the existing earth, except for drilling. There is no back footing to these walls, so it enables workers to assemble the wall from the top down.

?EUR??,,????'??There are no footings,?EUR??,,????'?? Hood said. ?EUR??,,????'??The anchors support the wall as it goes down. The bottom of the wall rests on the ground.?EUR??,,????'??

As visitors are carried up the hill towards the arrival plaza, they can see more than 8,500 native oak trees planted in rows on the hillside; deer, birds and other local wildlife are visible sometimes as well. The hillside?EUR??,,????'???s ground layer has been planted with poverty weed, local chaparral and shrubs, to prevent erosion and fire and preserve the natural environment. The landscape of the property was designed by Philadelphia based-Olin Partnership, and won an American Society of Landscape Architects design honor award.

According to archival information from the Getty Center, the landscape design is inspired by the garden traditions of California and the ancient Mediterranean. The landscaping contributes to the Center?EUR??,,????'???s mix of ancient and modern. As time passes, the landscape will evolve, creating an intimate, ever-changing area that enhances the artistic and educational mission of the museum.

Landscaping the Getty Center has been a collaborative effort involving many landscape architects, consultants and craftspeople through the years. Emmet Wemple, landscape architect for the Getty Villa in Malibu began the project and conceived preliminary designs. Richard Meier conceived the master plan that called for developing 19 of 24 acres as landscape or gardens. Dennis Hickok of Richard Meier & Partners served as liaison and for design and development of the works for the architects and landscape architects. Olin Partnership started on the team in 1992 and remained through the completion. Fong and Associates of Orange County, Calif., and Raymond Hansen assisted in plant selection, procurement, and administration; Daniel Urban Kiley consulted on the project beginning in 1990.

Now the work of Drill Tech and Boulderscape can be added to this list of people and firms who have worked to make the Getty Center the important institution it is today, where people from all over can come to see magnificent works of art. It?EUR??,,????'???s all right if visitors don?EUR??,,????'???t notice where the sculpted nail walls begin and end on their drive into the Center, they?EUR??,,????'???re not supposed to.

A light base color was applied to the wall, then two additional colors to highlight and add shadowing, enhancing the wall?EUR??,,????'???s three-dimensional appearance. Later an anti-graffiti coating was applied. The color scheme matches the dark greens and browns of the surrounding vegetation.