This review of selected segments of the stream-gaging network of Brazil was undertaken by the writer in March and April, 1973, pursuant to an agreement between Companhia de Pesquisa de Recursos Minerais (CPRM) and Centrais Eletricas Brasileiras S.A. (ELETROBRAS) as a part of the cooperative program of the U.S. Geological Survey (USGS) and CPRM under the auspices of the Ministerio das Minas e Energia (MME) and the U.S. Agency for International Development (USAID). Its primary purpose is to provide an evaluation of the adequacy of streamflow data on streams which are being considered for or are already being utilized for hydroelectric power sources. Some comments are included pertaining to the general coverage hydrologic network. These comments were generated by the examination of the streamflow data useful for power purposes because all gaging stations form a part of the total network for hydrologic investigations. Present plans are that the entire network will eventually be operated by or under the jurisdiction of the MME through the Departamento National de Aguas e Energia Eletrica (DNAEE).

Brazil is a large country, larger than the conterminous United States, and it has been engaged in hydrologic investigations for more than 50 years. The network has been maintained by Federal agencies, State agencies, power companies, and consulting firms and until recently no organizational mechanism existed to coordinate the various activities or to establish uniform standards of data collection, computation, and publication.

It is estimated that stage and/or discharge data have been collected at 2,500 or more sites in Brazil. Because there has been no centralized publication system, it has not been possible to locate with assurance all measurement sites or to ascertain precisely the types and quality of the data collected or available.

For these reasons the suggestions outlined in this report are expected to be modified on the basis of local need and site information, which may not have been evident at the time of the review. For example, specific suggestions have been made to discontinue some stations which appear superfluous or which essentially duplicate other stations. In other instances additions to the network have been proposed. There may be reasons for the continued operation of a given station which cannot be discerned from the available literature. Also coverage may have been established in an area but the evidence has not yet appeared in print. DEAEE is currently (1973) working diligently to overcome a backlog of data computation and publication. Brazil is currently developing at a rapid rate with electric power demands increasing at a 12% annually, a reflection of the tremendous growth of the economy. With this rate of increase likely to continue for the foreseable future, it goes without saying that hydrologic information needed tomorrow must be collected today.