PACKAGE : I Bid Document VOLUME : II - Public Health Engineering

xx) Air blower of 500 cfm capacity at 5 psi complete with motor and
accessories and pneumatically operated bypass valve.
DTS : Detailed Tender Specification. Page 237
1 no.
xxi) 80mm C.I. ring main connecting blower to filters. 1 range.
xxii) 80mm C.I. air valve with pneumatic cylinder and air piping
connection to control console. 12 nos.
xxiii) Wash water tank filling pump of capacity approx. 60 lps at 20m
head with suction pipe in filtered water sump and delivery header
and piping to wash water tank. Starter of pump inter-locked with
alarm indicated in (xviii) above.
xxiv) Control console, housing air cylinder operating four port valves,
R.O. F & L.O.H. indicator alarm and dials, rate setter wheel and
scale, air pressure gauge, glower starter station, wash water tank
level indicator. Console with sun mica on M.S. frame.
.
xxv) Garage type air compressor complete with motor air vessels autopressure
switch and other accessories for providing compressed air
for operating pneumatic cylinders.
2 nos.
6 nos.
1 no.
xxvi) (a) Syphon 600mm wide (C.I.) 36 nos.
(b) B.M Syphon activators with G.I. piping to siphon. 12 sets.
The different components of the 34.05 MLD Water Treatment Plant were designed
and constructed based on the raw water quality prevailing during the period of late
70s and early 80s where the turbidity of water does not exceed 50 PPM.
From the late 90s onwards, the turbidity of raw water has increased considerably on
account of stone and sand quarrying activity in the catchment at the upstream
reaches of the Umiew river. The turbidity during the period from April to October is
in the range of 350-1500 NTU and during the off monsoon months ranges between
100 to 350 NTU. On account of the high turbidity of water during the monsoon
months, the clari-flocculator of the existing 34.05 capacity WTP has become
overloaded adversely affecting the functioning of the Filtration Plant on account of
increased frequency of backwashing.
The water treatment units of the 34.05 MLD WTP of the existing project
viz. Plant, equipments & machineries like valves of different sizes, drives,
backwash pump, air blower and control panel etc. has outlived the designed life and
are proposed for replacement with plant, equipments & machineries which are
compatible with automation control and visualization system under a separate
scheme and outside the scope of this package.