HISTORY OF COLCHESTER CORPORATION WATER WORKS 33
works, probably does not exceed, say, 550,000 gallons, or about
one-seventh of that percolating into the formation; consequently
there is a considerable quantity of water escaping along the
fringe of this plateau of gravel in the shape of visible and invisible
springs other than those mentioned, and feeding the rivers
and streams bounding the gathering ground and ultimately
finding its way into the river Colne.
In order to thoroughly and efficiently protect the springs
from pollution, an area of no less than 291/2 acres of land has been
acquired at the back of the springs in a south-westerly direction,
which is also the direction the underground water is flowing;.
Upon this land no manure or grazing of cattle is allowed.
As an additional protection, there is a second zone around each
spring, enclosed with an unclimbable fence.
In addition to the precautions mentioned, the springs are
zealously guarded by Mr. Bland, and the water therefrom is
examined periodically, both chemically and bacteriologically,
by the Medical Officer of the Corporation, and I am not aware
that the health of the town has suffered in any way from the
adoption of these springs as an auxiliary source of supply.
My excuse, if any is needed, for writing at length upon these
interesting springs, is to impress upon communities, both large
and small, that they may be situated in proximity to a supply of
water within sight of their doors, and all that is needed to bring
it into use is a little common sense combined with geological,
medical, chemical, and engineering skill. Prejudice has existed
in the past against so-called surface springs, but all water which
we consume, whether it has been collected from the moors or the
hillside, and impounded in reservoirs, or taken from rivers and
stored in storage reservoirs and filtered, or pumped from wells in
permeable or under impermeable formations, has at one time or
another been in contact with the surface. Even a well sunk
into the open chalk is as liable to be polluted by man as a gravel
supply, if not protected, and especially if the cone of depression
caused by pumping extends to a distance, as illustrated by those
interesting experiments with fluorescine lately conducted by
the Local Government Board at Fulbourne in Cambridgeshire.
There are some towns so situated along the coast, and par-
ticularly in East Anglia, whose means are not sufficient to go