Presenting Nature

Cover

Contents

Foreword

Acknowledgements

Overview

Stewardship

Design Ethic Origins
(1916-1927)

Design Policy & Process
(1916-1927)

Western Field Office
(1927-1932)

Park Planning

Decade of Expansion
(1933-1942)

State Parks
(1933-1942)

Appendix A

Appendix B

Bibliography

Presenting Nature: The Historic Landscape Design of the National Park Service, 1916-1942

IV. THE WORK OF THE WESTERN FIELD OFFICE, 1927 TO 1932 (continued)

DESIGN OF PARK ROADS

Building on the years of experimentation in the 1920s, Vint's office made substantial advances in the road-building program and the Bureau of Public Roads work in national parks in the period from 1928 to 1932. During these years, the landscape architects became more and more experienced in the principles of harmonious design and the design of park roads and structures. Their drawings became increasingly detailed, and by 1930, they were providing road engineers and contractors with detailed designs for intersections, parking areas, loop developments, guardrails, and the treatment of road banks. Not only did they design the elevations of the bridges but they also provided detailed diagrams of the arch rings and masonry. Masonry techniques based on standardized principles of construction and adaptable to local stone evolved. Specific practices were developed, such as protecting important rockwork and trees in the vicinity of construction sites and locating work camps in the right-of-way rather than beside the road where they would disturb the roadside scenery and require restoration. The landscape architects supervised various aspects of road construction, paying particular attention to the effects of construction on scenery and natural features and to the harmonization of all built structures. The landscape architects approved the site of borrow pits, stone-crushing operations, quarries, and work camps. They gave instructions on site to the foremen and work crews on the proper technique for all masonry work, whether for bridges or guardrails. They approved the stone used based on weathered appearance, coloration, and availability and gave careful directions for the shape and size of stones, the width of mortar joints, and the way that stones were laid to ensure the greatest harmonization possible with the natural setting.

As the program expanded, a number of landscape problems arose. Foremost was the destruction caused by blasting and burning. Although in 1928 the National Park Service drafted an amendment to the interbureau agreement inserting more stringent guidelines for the protection of park scenery, the situation was finally settled by a letter clarifying the role of the National Park Service landscape architect in all park road work and by special provisions in the specifications of future contracts. Writing the engineers in charge of park work in October 1928, J. A. Elliot, the Bureau of Public Roads's senior highway engineer defined this role:

There are certain features in the construction of roads within the National Parks which require the approval of the Landscape Architect, such as parking areas, loop development, the type of guard rail to be constructed, location and extent of each type of rail, trees to be taken out under advance clearing operations, etc. The Landscape Architect is anxious to receive suggestions from the engineer, realizing that he is in close contact with the work and cognizant of all the features upon which the particular design depends. The Landscape Architect is responsible to the National Park Service and in order to avoid any misunderstanding on our part and to guarantee construction conforming with the Landscape Architect's ideas you must receive in writing from the Landscape Architect or his representative a statement on the above points before any orders or instructions are issued to the con tractor. In the case of the parking areas and loop developments a sketch will be furnished showing the proposed treatment of the area. Strict compliance with the above instructions is imperative. [15]

In the first several years of park service and bureau cooperation, specifications were carefully worked out for each project, whether a section of road or a group of bridges, and made available to contractors interested in bidding on the work. Vint was determined not only to streamline the process but also to ensure that the advances made in masonry techniques and landscape protection were understood and carried out by road engineers and the contractors. Having become director upon Mather's illness in 1928 and death the following year, Horace Albright gave Vint freedom to make improvements that emphasized the landscape standpoint in the building of roads.

PROTECTION OF THE LANDSCAPE

In 1929, Vint's division developed a standard list of general provisions covering the points that were common to each project and that could be translated into specifications for all projects. The provisions were intended to advance the goals of landscape protection and stewardship. They included many of the improvements that had evolved during the landscape architects' experience in road building since the mid-1920s. They emphasized the importance of landscape preservation, prohibited destructive practices of excavation through blasting, and described the standards for masonry work that had been incorporated in the plans for bridges and guardrails. Innovative was the introduction of type B excavation, which provided for careful rock excavation to avoid damage to outstanding natural features at specific sites. In June 1929, Director Albright approved the new provisions.

The general provisions for all park road projects called for the protection of natural features during construction in several ways. Special care was to be given to the protection of natural surroundings and adjacent campgrounds. Any timber or other landscape features scarred or damaged by the contractor's operations were to be removed, trimmed up, or restored as nearly as possible to their original condition at the contractor's expense. Special procedures for excavating earth and rock were incorporated to minimize the destruction and casting of debris caused by a blasting process called shooting. The contractor was to remove unsightly rock falling outside finished slopes. Contractors were required to limit the development of temporary trails and roads. They were allowed to clear a margin of land only as wide as the road, and trees and bushes were to remain uncut along the shoulders where they protected the surrounding woodlands or meadows from damage during construction. Trees and shrubs of "value to the appearance of the roads" were to be preserved. All holes left by removal of stumps and roots were to be back filled. Borrow pits were to be located in areas not visible from the completed road "in bushy draws adjacent to the road." The provisions also included detailed instructions and requirements for masonry construction of walls, bridges, guardrails, and the headwalls of culverts. [16]

Particularly significant were the new specifications for type B excavation. These specifications clearly prohibited practices such as block holing, in which gopher- and coyote-sized holes were drilled and planted with powerful explosives, which broke apart large masses of rock and earth when detonated, creating extensive rock falls and scarring. During such blasting, engineers had little control over the extent of the blast, the scarring and pitting that would result along the road, or the distance to which harmful debris would be cast, damaging the natural environment and scenery. Several cases gained Mather's attention. The greatest damage had occurred during the construction of the East Entrance Road in Yellowstone and the Transmountain Road in Glacier, where excavation debris was carried far down the slopes. Mather and Vint witnessed similar destruction on the Yakima Park Road when they visited Mount Rainier in July 1928. Mather immediately sent a photograph to Thomas MacDonald, chief of the Bureau of Public Roads, with a letter saying, "There is evidently an advantage in moving as much material as possible at once but when it results in such destruction as this it is entirely away from the principles that you and I have established." [17]

Although the problem was brought to the attention of the bureau and the contractor, heavy blasting continued on the Mount Rainier road. It appeared that the road engineers were not aware of the restrictions on shooting and were little concerned with specifications, preferring to build roads according to "common sense and good engineering." From the viewpoint of economics and maintenance, Chief Engineer Frank A. Kittredge agreed with the need for stricter requirements and called for their enforcement. He explained the technical problems:

There is no question but what the coyote or gopher hole shooting is much more practical from the contractor s point of view. Furthermore, these gopher holes are placed clear back against the toe of the slope and there is no question but that in many places the shaking of this gravel formation brings down large quantities of material which would not need to be removed if taken out with a shovel or by other types of shooting. Furthermore, the shaking of the hillside makes it possible for the water to gain access to the back slopes and with the constant freeze and thawing of the next few years after construction there is bound to be a large amount of inflow which must be removed at the park's expense under Maintenance. [18]

Vint and his staff developed the methods for type B excavation in consultation with bureau engineers and a representative of the Dupont Powder Company. The methods called for modified blasting procedures to be used in designated areas to prevent damage to surrounding objects and to eliminate the scattering of rocks, stumps, and other debris outside finished slopes. Gentle, controllable techniques for breaking surface boulders or rock fragments, known in the field as plastering and mudcapping, were approved, while block holing was prohibited. Practices for blasting and sidewall excavation that used "gopher" and "coyote" holes were prohibited. [19]

The provisions were added to each contract in the form of a checklist and were to be incorporated into the 1929 contracts for new work at Lassen, Yellowstone, and Rocky Mountain and all future contracts. The inclusion of this specification in all contracts provided the landscape engineers a mechanism for giving special protection to landscape features at places where normal methods of excavation were likely to cause considerable damage. Landscape architects were to identify particular locations—in terms of stations and distances—requiring the modified methods of excavation during their preliminary road surveys and note them in the survey reports. Because type B procedures were likely to increase the costs of road building, only work in those areas identified in the contract were affected. [20]

Continued >>>

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