, 1889-07-10

4. sub Item D. 9. The Road Department,
Streets &c., there is hereby granted, for
repairing the Grange bridge. $500 81, 10000
and the total under this item is
to be carried out with........... 2,850.00
REMARKS.
After the repair of the Grange bridge for
which a sum of 5000 was granted on the
Budget for 1867, had been completed, the
bridge stood uniniured till January 1888, when
the West end of the southern pier, together
with the covering wall abutting on it, began
to sink and to slide outwards, and, as a con
sequence, large rents appeared.
Thus the. damage TO the bridge shewell Il,
self in the same place where the earlier
damage had been. 1t had been done some,
time after the heavy rains towards the close
of 1887, but it was not clear whore the water
which loosened the ground came from, since
1T could either be attributed to springs in
the ground, which was a common opinion, or
could be attributed directly to the surface water
which in heavy rains made a way for itself
to the earth under the foundation of the
bridge. AS it was, Of course, important to
clear up this point before the thorough repair
OF the bridge was undertaken, and as the
condition of the bridge was not such that it
nlLuSEGu lI6 GEdluC DT ultI6 II uuSdIS, GIl0
Government decided that for the time only
some minor measures should be taken tor
supporting the wall work and for preventing
the water from the intercourse itself from
forcing its way in under the foundation of
the bridge, and then to await the effects of
the next heavy rains.
These came in November 1888 and afford.
ed the calculations which were wanting.
The damage to the bridge was continued,
as was to be expected. Observations made
by the Building Inspector during the actual
fall of the rain showed, that the mass of water
IN the water course was greatly swollen, but
that the water way under the bridge was
large enough to give the water free course
on the surface of the road itself there ran
strong streams Of water from the north and
south down upon the bridge, which lies III a
hollow in the land. The want of regular road
trenches with secured outlet channels round
the bridge down to the water course caused
this mass Of water to collect over the bridge
itself, pressing against the western side-wall
and passing round it's southern end into the
ground. Now as the ground on the western
side of the bridge consists of clay, which
sottens and becomes a flowing mass under
the action of running water, the cause of the
destruction is plain enough: it is not the
mHSS Vi WAFER IN GQ0 wafer course lGS6lI, nor
springs in the ground, which cause it, but
the water which falls on the surface of the
road.
The repair must consist in securing the
foundations of the western ends Of the bridge
piers by piling, in laying Town broad, paved
cutters for carrying off the water from the road
and the road-trenches round outside the bridge
SO that it cannot do any damage thereto, and
also in regulating the water-course at the
part nearest the. bridge. The Road Autho-
rites must also see that the road which leads
to the bridge is provided with broad and
deep trenches and that it has such d cross
section that the water does not remain on
the surface of the road, but is led into the
trenches.
In what way it is contemplated to repair
the bridge will appear from the proposal of
the Building Inspector, which, with a draw
ing and estimate. is laid on the Councils
table.
The expenses are therein stated at 81, 100,
in which is included the outlay for the
actual repairs of the bridge, for securing the
carrying off of the water from the road.