[Report of the Medical Officer of Health for Chislehurst] page 56

Chislehurst 1959

[Report of the Medical Officer of Health for Chislehurst]

This page requires JavaScript

Table: Average Results of the Bacteriological Examination of the water supplied to the Urban District of Chislehurst and Sidcup during1959.

Download table as:

Average Results of the Bacteriological Examination of the water supplied to the Urban District of Chislehurst and Sidcup during

1959.

Source of Supply	Bexley	Eynsford Well	Eynsford Borehole	Orpington	North Orpington	Short-lands No. 1	Short-lands No. 2		Short-lands No. 3	Wilmington No. 1	Wilmington No. 2	Thames derived
Before Treatment
Number of Samples	250	229	175	252	245	65	187		251	137	152	—
Agar plate count per ml. 20-24 hours at 37°C.	1.0	0.1	0.1	0.2	2.3	0.1	0.1		0.4	0.7	2.0	-
3 days at 22°C.	4	9	3	3	23	1	2		3	44	95	-
Coliform count Percentage samples negative in 100 ml.	99.20	81.22	100	93.25	17.55	100	100		100	75.91	86.18	-
Count per 100 ml.	—	1.4	—	0.2	20.0	—	—		—	0.3	0.2	-
Escherichia coli count Percentage samples negative in 100 ml.	100	99.13	100	99.60	33.47	100	100		100	95.62	96.05	-
Count per 100 ml.	—	—	—	—	10.0	—	—		—	—	0.1	-
After Treatment
Number of Samples	255	258		257	250	257				257		3.344
Agar plate count per ml. 20-24 hours at 37°C.	0.3	0.1		0.1	0.9	0.2				0.1		9.8
3 days at 22°C.	2	25		7	2	1				0.2		—
Coliform count Percentage samples negative in 100 ml.	99.32	100		99.22	100	100				99.61		99.46
E. coli count Percentage samples negative in 100 ml.	100	100		99.6	100	100				99.6		99.97