Arizona republican., 1909-05-16
ROOM FOR ARGUMENT
 BRIDGE CONSTRUCTION
DIFFERENT PHASES OF THE IM-
 PoRTANT SUBJECT
Some Observation on a Timely Topic
 By James Goodwin.

In the morning Republican appeared an article headed "The Great Profits in Permanent Bridges" To read this article one would think that great mistakes have been made by building steel or other bridges than cement. They would have you believe that the life of a steel bridge is about 25 years and after that period they become useless. l passed over the St Louis bridge over 25 years ago, and l un- derstand they are still using it today. know of many other bridges that have been built even a longer time, that are still being used. It is true that steel bridges were permanent in time becomes less strong than when built. It was at first thought that seel bridges were permanent bridges. When the first reinforced concrete steel structures were built it was proclaimed far and near that the only permanent material for con- structing buildings and bridges had been discovered and that a bridge built out of these materials would grow stronger with age, yet it has been proven that this theory of perm anency is all fallacy. Scientific men in the employ of the government are making experiments to determine the deteriorating effect that electricity has upon these structures. It has been found that where electric cars pass over or near a reinforced concrete structure that an electric action is set up and the steel begins to cor rode. The best engineers we have to- day are fearful that the reinforce ment of steel in time will become a dctriment rather than a benefit for not only does 1t corrode and become brittle, but it deteriorates and de- strOys the cohesive force of the ce ment.
 But why quibble and cavil over these things? There are two other reasons why a bridge of the design proposed by the Phoenix Bridge Pub licity committee should not be built
 The first reason is: according to the survey made by the county sur Veyor, it will not span the river by over a thousand feet. There are many taxpayers in Maricopa county
 
 any bridge was ever built on the Salt or Gila rivers. The NJ. & P Co. built a bridge across the Gila river and they built a causeway, after the raise of 1891, their bridge was setting 2250 feet from the north bank of the river. This was a permanent bridge, but the repairs on this bridge cost the company perhaps s1O0,G0O. besides spending over s1OO,OOO for new bridge. The Florence bridge was built at a cost to Pinal county of many thousand dollars. After the flood in 1891 the cause ways on either end would have cost the county more to repair than the first cost of the bridge, and you taxpayers of Mari copa county are paying into the ter ritory treasury your part of s29.000 to help repair this bridge.
 The M. & P. bridge at Tempe after the flood of 1891, and other floods, was 1000 feet south of the north bank of Sat river. Here was another causeway gone. They spent many thousand dollars trying to repair this bridge, and finally repaired 1t by abandoning it and building a complete new bridge
 The Santa Fe bridge across the river at Tempe was built on con- crete piers, practically the same kind of pier and built in the same man. ner as proposed to be built on Center Street bridge. After a heavy flood one of these piers was cut out and disappeared and no one has ever seen it or seen any part of it to this day It cost this company many thousand dollars for temporary repairs, and the gap still remains in the bridge.
 l do not think that there is an engineer in Arizona but who would recommend and advise that a caisson cylinder pier (the type that is used by the NJ. X P. at Tempe) would be the only type that could be recom- mended for permanency, for of all the bridges that have ever been built on the Salt or Gila rivers, this is the only pier that has stood. I think MT. Hill of the reclamation service, Mir Ingalls,, surveyor general of the terri ritory, or our territorial engineer, would recommend this type at either place, but I have my doubts about either of these gentlemen recommend ing the kind of a structure that is proposed for Center street, so after all it has been the history of the bridges built both on the Salt and Gila rivers that the first cost has not been the greatest cost where bridges were built with causeways and fills, or bridges part way across the river. so even if the type of bridge that is proposed to be built at Center street should stand. there is a thousand feet yet of fills that may be the river of tomorrow, and what we, the taxpayers would like to know is, that among all of the good civil engineers there are in Maricopa county, how many will recommend the type of bridge and it's permanency that is proposed to be built at the foot of Center street?
 JAMES c. GOODWIN.