Rock Island Filtered Water

Rock Island Filtered Water

The following report has been received from Professor Edward Bartow, Director of the State Water Survey at Urbana, Ill., on the analysis of samples of the raw and filtered water of Rock Island, submitted by Commissioner John A. Murrin: There are 110 parts in a million of turbidity in the water from the raw water intake pipe and from the sample taken from the city tap all turbidity has been removed. The analysis of the treated water shows that fourfifths of the color has been removed and onehalf the odor. There are 25 parts of color in the raw water and five in the filtered and the odor of the unfiltered water is 2v, while the sample from the city tap showed lv. In the city water there was a residue of 179 parts left on evaporation and the water from the intake pipe left 289 parts when evaporated. The amount of chlorine in chlorides has been increased in the filtered water. The amount in the raw water was 36 parts and two parts have been added during the process of filtration. Oxygen consumed in the untreated water amounted to .3 parts in a million and in the water from the tap the quantity was 3.8. Nitrogen has not been entirely removed from the filtered water but exists as follows:’ Free ammounia, .168; albuminoid ammonia, .162; nitrates, .88. Nitrogen was present in the raw water as follow's: Free ammonia, .23; albuminoid ammonia, .346; nitrites, .01, and nitrates, 1.12. The alkalinity of the water has been reduced 20 parts. In the raw water it is 146 parts and the clear watex 126. Bacteria were present in the unfiltered water when cultivated in gelatine, 28,800 for every cubic centiiqeter and in agar, 16,400 in a cubic centimeter. After the water had been treated 6 bacteria were present in a cubic centimeter in gelatine and 7 in a cubic centimeter cultivated in agar. Gas formers in the intake pipe were present in the following amounts: 10 ccm., one plus; 1 ccm., 2 plus and 1 ccm., 2 minus. The sample from the city tap gave the following results: 10 ccm., one; 1 ccm., two, and .1 ccm., three minus. The summary at the end of the report, on the raw' water, stated : “Contamination is indicated—water should not be used for drinking purposes unless properly treated.” The summary of the filtered water was: “Comparing this analysis with that of the raw water, we note a satisfactory removal of bacteria and suspended matter. The water is safe for drinking purposes.”

The following report has been received from Professor Edward Bartow, Director of the State Water Survey at Urbana, Ill., on the analysis of samples of the raw and filtered water of Rock Island, submitted by Commissioner John A. Murrin: There are 110 parts in a million of turbidity in the water from the raw water intake pipe and from the sample taken from the city tap all turbidity has been removed. The analysis of the treated water shows that fourfifths of the color has been removed and onehalf the odor. There are 25 parts of color in the raw water and five in the filtered and the odor of the unfiltered water is 2v, while the sample from the city tap showed lv. In the city water there was a residue of 179 parts left on evaporation and the water from the intake pipe left 289 parts when evaporated. The amount of chlorine in chlorides has been increased in the filtered water. The amount in the raw water was 36 parts and two parts have been added during the process of filtration. Oxygen consumed in the untreated water amounted to .3 parts in a million and in the water from the tap the quantity was 3.8. Nitrogen has not been entirely removed from the filtered water but exists as follows:’ Free ammounia, .168; albuminoid ammonia, .162; nitrates, .88. Nitrogen was present in the raw water as follow's: Free ammonia, .23; albuminoid ammonia, .346; nitrites, .01, and nitrates, 1.12. The alkalinity of the water has been reduced 20 parts. In the raw water it is 146 parts and the clear watex 126. Bacteria were present in the unfiltered water when cultivated in gelatine, 28,800 for every cubic centiiqeter and in agar, 16,400 in a cubic centimeter. After the water had been treated 6 bacteria were present in a cubic centimeter in gelatine and 7 in a cubic centimeter cultivated in agar. Gas formers in the intake pipe were present in the following amounts: 10 ccm., one plus; 1 ccm., 2 plus and 1 ccm., 2 minus. The sample from the city tap gave the following results: 10 ccm., one; 1 ccm., two, and .1 ccm., three minus. The summary at the end of the report, on the raw' water, stated : “Contamination is indicated—water should not be used for drinking purposes unless properly treated.” The summary of the filtered water was: “Comparing this analysis with that of the raw water, we note a satisfactory removal of bacteria and suspended matter. The water is safe for drinking purposes.”