OBJECTS AND ORGANIZATION OF THE WORK 



The objects of the survey were to determine the extent of the damage from 

 marine borers in San Francisco Bay, especially that of epidemic severity which had 

 occurred within the preceding three years in the northern portion of the bay; to de- 

 termine the present distribution of the several marine borers and as much of their 

 past history' in the bay as it was possible to learn; to increase the present knowledge 

 of the dissemination, growth and habits of the borers; to study the factors influencing 

 the rate of attack and amount of damage from them, including the effects of climate 

 and river discharge upon the salinity conditions in the bay; to throw more light 

 upon the effectiveness, lioth in physical life ami economic advantage, of the \'arious 

 methods of protecting wooden piling, and of the substitutes for it, together with the 

 best methods of construction which had been de\-eloped; and to collect data on the 

 relative costs of the different methods of protection and construction. 



In order to accomplish these objects, the investigation was organized during the 

 first half year, or preceding the first report, along the following lines: 



1. HYDROGRAPHIC PHASE 



This phase had to do with the effect of climatic conditions and river discharge 

 upon the salinity of the water in the northern arm of San Francisco Bay and its tribu- 

 taries. This part of the survey was entrusted to Mr. C. E. Grunsky and Captain 

 C. S. Jarvis, whose eminence in that field, as well as their familiarity with the condi- 

 tions and problems of the Sacramento and San Joaquin Rivers and their watersheds, 

 particularly fitted them for this service. 



2. BIOLOGICAL PHASE 



This phase had to do with the present distribution of marine borers, their past 

 history, their dissemination, growth and habits, and the factors influencing their 

 rate of attack and the resulting damage. This part of the survey was entrusted to 

 Professor Chas. A. Kofoid, whose preeminent position in this field made his av'ail- 

 ability to the Committee peculiarly fortunate. 



3. ENGINEERING PHASE 



This phase had to do with the design, construction, maintenance and repair, 

 with their costs, of marine waterfront structures subject to the attack of marine 

 borers, and covered an investigation of many different methods of protection against 

 such attacks. The sound guidance of this phase of the work was amply assured by 

 the number and eminence of the engineers who not only have been enrolled in the 

 committees but who have devoted themselves actively to the prosecution of its 

 labors. During the most important part of the initial year's survey, the Committee 

 was fortunate in having the personal assistance of Mr. George M. Hunt, Chief of 

 the Section of Wood Preservation of the Government Forest Products Laboratory at 

 Madison, Wisconsin. Following the initial period, the engineering field work was 

 conducted by Mr. H. M. Goodman, Engineer of the Committee, under the direction 

 of the Chairmen of the Sub-Committees on Service Records and Wharf Construction. 



DEVELOPMENT OF THE SURVEY 

 A questionnaire was first sent out to the owners of all important waterfront struc- 

 tures in San Francisco Bay and its tributaries, the returns from which not only fur- 

 nished valuable information to the Committee but also helped in the planning of 

 the various stages of the field investigations. On account of the peculiar problems 



