pointed to succeed him. The hydroelectric generating station at Gatun, the reserve steam-driven electric-generating plant at Miraflores, the substations, transmission lines, and power-distributing systems throughout the canal were all satisfactorily maintained and operated. This division also continued to install, maintain, and operate the municipal and house lighting systems, the telephones and telegraphs, fire alarm, and the railway block signals and interlocking plants. The average monthly consumption of electricity generated for all purposes was 3,645,325 K. W. H., at a cost, including depreciation, of $0.0073 per K. W. H. consumed for power purposes, and $0.0134 for lighting purposes, the latter figure including maintenance of interior house wiring and lamp renewals. The new water wheels, referred to in last year's report, were installed at the Gatun spillway, resulting in an increased capacity from 6,000 K. W. to 8,640 K. W., at 80 per cent power factor. This work was completed December 19, 1916, at a cost of $16,377.91. Funds were provided for the installation of an additional unit and the extension of the station building to accommodate this unit and provide space for the future installation of two more units. This work was begun on January 1, 1917, and at the end of the year the concrete draft tubes and the foundations of the building extension were completed and the erection of penstocks 10 per cent completed. A contract was made on November 22, 1916, for the construction of the new generator unit, to be delivered on December 2, 1917. This generator will be a General Electric 66,000-volt, 3-phase, 25-cycle, 4,500 K. W., at 80 per cent power factor, mounted on a vertical shaft direct connected to a 6,750 H. P. turbine furnished by the Pelton Waterwheel Company. With the changes heretofore made in the three water wheels originally installed, this additional unit will increase the capacity of the Gatun station to 13,140 K. W., and the ultimate capacity provided for when the two additional units are installed will be 22,140 K. W. This will take care of about twice the present load and will make available a reserve of about 50 per cent above any increases in load now in contemplation. The work of installing in the Miraflores station the units from the dismantled steam-power plant at Gatun was completed on December 14, 1916. This installation increased the capacity of the Miraflores: station to 7,200 K. W. The steady growth of the electric load on, the canal has made nece flores plant to carry t of the Gatun hyd plant provides r power system he intermittent operation of the Mirang the increase in capacity, a reserve the Miraflores ck and the lighting and 1 at times of breakons of power from ads carried during 1917 were: Balboa coaling plant, 1,267 K. W.; Balboa dry dock, 6,040 K. W.; air-compressor plant at Balboa, 1,600 K. W.; cold storage and ice plant, Balboa, 450 K. W.; and additional lights requiring 1,300 K. W. in the various municipal buildings, schools, and Army and canal quarters. To provide an adequate reserve at the Miraflores plant it will be necessary to increase its capacity so as to maintain it at about two-thirds the capacity of the Gatun plant. The necessity for increased electrical output has led to a consideration of the water consumption from Gatun Lake by the Gatun hydroelectric station and its effect on the level of Gatun Lake during the four months' dry season. The dry season of 1917 was abnormal in length and in deficiency of rainfall, and as the traffic through the canal was above the average and the consumption at the hydroelectric station increased, an opportunity was afforded to observe the fall in lake level under conditions of large consumption and small inflow of water. The results are discussed in the part of this report relating to meteorology and hydrography. It may be stated here, however, that it will be necessary, with a pronounced increase in canal traffic, to operate the hydroelectric station at less than its ultimate capacity during dry seasons and to supply the deficiency in electric power by the operation of the Miraflores plant during the corresponding periods. There was a large increase in telephone service during the year. On June 30, 1916, 1,878 telephones were in use, and on June 30, 1917, 2,154. The average number of telephone calls per day was 21,042. To care for the increase in telephone business plans are developing for a new exchange at Cristobal and the installation of additional cable for trans-isthmian service. The construction work of the division included the laying of 185,000 feet of underground cable and the installation of lighting systems in 86 Army buildings, 45 Panama Railroad buildings, and 991 apartments for canal employees. For further details attention is invited to Appendix A. MUNICIPAL ENGINEERING DIVISION. This division continued under the immediate charge of Mr. D. E. Wright, as municipal engineer, reporting to the engineer of mainteance. The work of the division consisted of the maintenance and pair of municipal improvements in the Canal Zone and in the cities of Panama and Colon, the care and maintenance of the water reserthe maintenance and operation of the pumping stations and plants. In addition to the maintenance work ed all road and municipal construction work f or the canal, and similar work in the Army! or pointed to succeed him. The hydroelectric generating station at Gatun, the reserve steam-driven electric-generating plant at Miraflores, the substations, transmission lines, and power-distributing systems throughout the canal were all satisfactorily maintained and operated. This division also continued to install, maintain, and operate the municipal and house lighting systems, the telephones and telegraphs, fire alarm, and the railway block signals and interlocking plants. The average monthly consumption of electricity generated for all purposes was 3,645,325 K. W. H., at a cost, including depreciation, of $0.0073 per K. W. H. consumed for power purposes, and $0.0134 for lighting purposes, the latter figure including maintenance of interior house wiring and lamp renewals. The new water wheels, referred to in last year's report, were installed at the Gatun spillway, resulting in an increased capacity from 6,000 K. W. to 8,640 K. W., at 80 per cent power factor. This work was completed December 19, 1916, at a cost of $16,377.91. Funds were provided for the installation of an additional unit and the extension of the station building to accommodate this unit and provide space for the future installation of two more units. This work was begun on January 1, 1917, and at the end of the year the concrete draft tubes and the foundations of the building extension were completed and the erection of penstocks 10 per cent completed. A contract was made on November 22, 1916, for the construction of the new generator unit, to be delivered on December 2, 1917. This generator will be a General Electric 66,000-volt, 3-phase, 25-cycle, 4,500 K. W., at 80 per cent power factor, mounted on a vertical shaft direct connected to a 6,750 H. P. turbine furnished by the Pelton Waterwheel Company. With the changes heretofore made in the three water wheels originally installed, this additional unit will increase the capacity of the Gatun station to 13,140 K. W., and the ultimate capacity provided for when the two additional units are installed will be 22,140 K. W. This will take care of about twice the present load and will make available a reserve of about 50 per cent above any increases in load now in contemplation. The work of installing in the Miraflores station the units from the dismantled steam-power plant at Gatun was completed on December 14, 1916. This installation increased the capacity of the Miraflores station to 7,200 K. W. The steady growth of the electric load on the canal has made necessary the intermittent operation of the Miraflores plant to carry the peak loads pending the increase in capacity of the Gatun hydroelectric station. As a reserve the Miraflores plant provides power for the Pacific locks and the lighting and power systems at the Pacific terminus of the canal at times of breakdown in the transmission lines or other interruptions of power from the Gatun plant. The principal additional loads carried during 1917 were: Balboa coaling plant, 1,267 K. W.; Balboa dry dock, 6,040 K. W.; air-compressor plant at Balboa, 1,600 K. W.; cold storage and ice plant, Balboa, 450 K. W.; and additional lights requiring 1,300 K. W. in the various municipal buildings, schools, and Army and canal quarters. To provide an adequate reserve at the Miraflores plant it will be necessary to increase its capacity so as to maintain it at about two-thirds the capacity of the Gatun plant. The necessity for increased electrical output has led to a consideration of the water consumption from Gatun Lake by the Gatun hydroelectric station and its effect on the level of Gatun Lake during the four months' dry season. The dry season of 1917 was abnormal in length and in deficiency of rainfall, and as the traffic through the canal was above the average and the consumption at the hydroelectric station increased, an opportunity was afforded to observe the fall in lake level under conditions of large consumption and small inflow of water. The results are discussed in the part of this report relating to meteorology and hydrography. It may be stated here, however, that it will be necessary, with a pronounced increase in canal traffic, to operate the hydroelectric station at less than its ultimate capacity during dry seasons and to supply the deficiency in electric power by the operation of the Miraflores plant during the corresponding periods. There was a large increase in telephone service during the year. On June 30, 1916, 1,878 telephones were in use, and on June 30, 1917, 2,154. The average number of telephone calls per day was 21,042. To care for the increase in telephone business plans are developing for a new exchange at Cristobal and the installation of additional cable for trans-isthmian service. The construction work of the division included the laying of 185,000 feet of underground cable and the installation of lighting systems in 86 Army buildings, 45 Panama Railroad buildings, and 991 apartments for canal employees. For further details attention is invited to Appendix A. Tance. MUNICIPAL ENGINEERING DIVISION. This division continued under the immediate charge of Mr. D. E. Wright, as municipal engineer, reporting to the engineer of mainteThe work of the division consisted of the maintenance and repair of municipal improvements in the Canal Zone and in the cities. of Panama and Colon, the care and maintenance of the water reservoirs, and the maintenance and operation of the pumping stations and water filtration plants. In addition to the maintenance work the division performed all road and municipal construction work for all new town sites for the canal, and similar work in the Army posts, Fort Grant, Fort Sherman, Fort Randolph, and Fort De Lesseps. The reservoirs and pumping plant on the west side of the canal, for the service of the military posts at Las Cascadas, Empire, and Culebra, were maintained and operated. At the Mount Hope pumping station the average number of gallons pumped a month was 119,169,500; at Agua Clara, 27,084,750; at Gamboa, 284,661,833; at Miraflores, 30,162,500; at Balboa, 205,171,250; and at Paraiso, 6,220,166. The average division cost for water delivered in the various districts per 1,000 gallons during the year was as follows: Cristobal, $0.06; Gatun, $0.11; Gamboa, $0.34; Paraiso, $0.07; Pedro Miguel, $0.07; Miraflores, $0.06; and Balboa-Ancon, $0.06. These figures include the costs of filtration and purification at the filtration plants at Mount Hope and at Miraflores. At Cristobal 47,257,000 gallons and at Balboa 14,558,000 gallons were sold to ships during the year. The municipal maintenance work performed in the cities of Panama and Colon, at a total cost of $152,289.89, was repaid to the municipal division from water rentals, in accordance with the terms of our agreement with Panama. In the city of Panama the average daily consumption of water for the year was 2,398,250 gallons, and in Colon 1,626,695 gallons. The principal items of construction by the municipal division for The Panama Canal consisted of the grading of grounds and the installation of water and sewer lines, streets, and sidewalks in the new addition to the town at Balboa, making fill and grading grounds and constructing water and sewer systems, streets, and sidewalks in the new town of Cristobal, and the construction of connecting roads in outlying districts. For those purposes the expenditures were $488,948.81. For the Army, $530,912.70 were expended in grading, installing water and sewer systems, and constructing streets and sidewalks at Fort Grant, Fort Sherman, and Fort Randolph, the construction of a concrete road from Fort Randolph to Mount Hope, from Fort Grant to Balboa, and the construction of roads, streets, water and sewer lines for the new Ordnance Depot at Corozal, and repairs to roads and streets in the camps at Culebra, Empire, Las Cascadas, and Quarry Heights. For the Panama Railroad there were constructed the G Street storm sewer in Colon, the railroad's share of the Curundu River storm sewer, the roads at the Cristobal piers, water lines for cattle pastures, roads to a number of the plantations, and improvements to pavements in the vicinity of the passenger station of Panama City. The cost of the work performed at the expense of the railroad was $126,849.40. Work done for outsiders. for which deposits were made to cover the cost, included the making of private water taps, the construction of short sections of road, and repairs to the tramway company's right of way in Panama City and to the streets in Panama and Colon that were opened up for the |