FLOOD AT MACOPIN DAM.

Mr. Morris R. Sherrerd, engineer of the Newark city water board, has furnished flow computations over Macopin intake dam, which is the head of the Newark pipe line. As about 73 per cent of the Pequanac drainage area lies above this intake, the table on page 16 shows roughly an equivalent percentage of the flow contributed by Pequanac River to the Central Basin of the Passaic. In consulting this table it should be borne in mind that the entire run-off of the drainage area above Macopin is about 25,000,000 gallons per day more than the amounts presented in this table. All reservoirs and ponds connected with the conservancy system of the Newark water supply were filled except that at Oakridge, which was about 1.5 feet below the crest of the spillway.

Flow of Pequanac River over Macopin dam, October 7-24, 1903.

[From Newark water department.]

Cubic feet.
Oct. 8,6 a. m. to 12 m. 240,600
12m. to 4 p. m. 347,600
4 to 6 p. m. 842,200
8-9,6 p. m. to 6 a. m. 40,110,000
9, 6 a. m. to 12 m. 51,870,000
12m. to 1 p. m. 15,100,000
1 to 5 p. m. 62,430,000
5 to 10 p. m. 89,040,000
10 to 11 p. m. 19,520,000
9-10, 10 p. m. to 8 a. m. 201,350,000
10, 8 a. m. to 12 m. 75,670,000
12 m. to 6 p. m. 103,650,000
6 to 12 p. m. 73,530,000
11, 12 to 6 a. m. 56,820,000
6 a. m. to 12m. 41,440,000
12 m. to 6 p. m. 32,755,000
6 to 12 p. m. 25,665,000
12, 12 to 6 a. m. 23,800,000
6 a. m. to 12m. 20,725,000
12 m. to 6 p. m. 18,450,000
6 to 12 p. m. 15,105,000
13, 12 to 6 a. m. 13,370,000
6 a. m. to 12 m. 11,890,000
12 m. to 6 p. m. 11,230,000
6 to 12 p. m. 11,230,000
14, 12 to 6 a. m. 9,626,000
6 a. m. to 12 m. 8,690,000
12 m. to 6 p. m. 8,022,000
6 to 12 p. m. 7,353,000
15, 12 to 6 a. m. 6,952,000
6 a. m. to 6 p. m. 12,700,000
15-16, 6 p. m. to 6 a. m. 10,965,000
16, 6 a. m. to 6 p. m. 10,025,000
16-17, 6 p. m. to 6 a. m. 9,091,000
17, 6 a. m. to 6 p. m. 8,690,000
17-18, 6 p. m. to 6 a. m. 9,893,000
18, 6 a. m. to 6 p. m. 10,565,000
18-19, 6 p. m. to 6 a. m. 8,690,000
19, 6 a. m. to 6 p. m. 6,952,000
19-20, 6 p. m. to 6 a. m. 6,150,000
20, 6 a. m. to 6 p. m. 5,882,000
20-21, 6 p. m. to 6 a. m. 5,749,000
21, 6 a. m. to 6 p. m. 5,481,000
21-22, 6 p. m. to 6 a. m. 5,214,000
22, 6 a. m. to 6 p. m. 4,144,000
22-23, 6 p. m. to 6 a. m. 3,677,000
23, 6 a. m. to 6 p. m. 3,877,000
23-24, 6 p. m. to 6 a. m. 5,749,000
24, 6 a. m. to 6 p. m. 5,615,000

FLOOD AT BEATTIE'S DAM, LITTLE FALLS.

The flow over Beattie's dam at Little Falls, has been calculated according to coefficients used for the same dam in Water-Supply Paper No. 88. Recorded gage heights show that over the main dam there was a maximum depth of 11.12 feet, which continued from 2 to 8 p. m., on October 10, representing a maximum flow of 31,675 cubic feet per second. (See Pl. I, A.) In the following table is set forth the flow of the river over Beattie's dam during the flood, and for purposes of comparison, the figures for the flood period of March, 1902. It should be borne in mind in consulting this table, that in the case of the flood of 1903 exact dates and hours are given, while the figures for the 1902 flood represent flow determinations at six-hour intervals, beginning with the initial rise of that flood.


U. S. GEOLOGICAL SURVEYWATER-SUPPLY PAPER NO. 92 PL. I