MARINE BORERS AND THEIR RELATION TO 



MARINE CONSTRUCTION ON THE 



PACIFIC COAST 



BEING THE 



FINAL REPORT OF THE SAN FRANCISCO BAY 

 MARINE PILING COMMITTEE 



HISTORICAL SECTION 



CHAPTER 1 



ORIGIN AND DEVELOPMENT OF THE SAN FRANCISCO BAY 

 MARINE PILING SURVEY PROJECT 



By C. L. Hill 



Early in the year 1914, the activity of marine borers was noticed in the dykes of 

 the Mare Island Navy Yard, at the upper extremity of San Pablo Bay, which is 

 the northern arm of San Francisco Bay (see frontispiece map), as well as at two 

 nearby points on the east shore of that bay. One of the latter was a dock between 

 Crockett and Vallejo Junction and the other a dock at Oleum, a mile or so south of 

 Crockett. Sporadic attacks of marine borers were reported to have been observed in 

 that region at isolated times running as far back as 1870, although no certainly au- 

 thentic records of them could be secured. In any case, however, such attacks were 

 of short duration and did no serious damage. 



For many years previous to the attack of 1914 the unusual facilities offered 

 around the shores of San Pablo Bay and the waterfront above that bay, including 

 Carquinez Strait, Suisun Bay, and the lower course of the Sacramento River, had 

 attracted many large industries. The waterfront structures erected by these varied 

 industries were all built on untreated piling, because of the absence of marine borer 

 activity in those waters and the belief that the fresh water discharged into San Pablo 

 Bay from the combined flows of the Sacramento and San Joaquin Rivers would 

 prevent any invasion of that area by salt water, sufficient to carry with it the various 

 forms of marine borers. 



The attack of 1914 appeared to be sporadic, like the earlier ones. But in 1917 

 attacks by the same shipworm, which was identified as a teredo, again appeared at 

 and near Mare Island, and during the following years spread very rapidly and in- 

 creased in severity. In the latter part of 1919 the attacks had progressed to such an 

 extent that parts of waterfront structures and in some cases whole docks began to 

 fail (fig. 1). In 1920 these failures assumed such proportions and became of such 

 frequent occurrence as to constitute a very critical local situation. On June 16, 1920, 

 this situation was brought to the attention cf officials of the American Wood Preserv- 

 ers' Association. As a result, a special committee was appointed on July 22, 1920, 

 to study the marine piling problem in San Francisco Bay, with instructions to report 

 at the Seventeenth Annual Meeting of that Association held at San Francisco in 



