PACKAGE : I Bid Document VOLUME : II - Public Health Engineering
PACKAGE : I Bid Document VOLUME : II - Public Health Engineering
PACKAGE : I Bid Document VOLUME : II - Public Health Engineering
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vii) This region has experienced a large number of major earthquakes during the last<br />
century. The area where the above intake is proposed to be built lies within the Iso-cysmal<br />
V<strong>II</strong>I-IX in the modified Barcelli Scale. Seismicity of the region is an important factor to be<br />
considered for the design of the Intake structure and other appurtenant works.<br />
viii) Minimum storage capacity of Intake well shall be 30 minutes storage at the lowest<br />
level of water in the reservoir and at average rate of pumping for 20 hours operation of<br />
pumps in a day to supply 24 MLD.<br />
ix) There will be 3 Nos. of inlet port sluice valves, which shall be of manually operated<br />
non-rising spindle type CIDF as per IS: 3042. The spindle of the sluice gate shall be of<br />
stainless steel and additional length of Stainless Steel spindle shall also be provided with<br />
intermediate line support bearing of phosphor bronze sleeve in CI casing at a regular<br />
interval of maximum 1.5 m shall be provided for operation of the sluice gate from top at<br />
the pump floor level. Diameter of the spindle shall be sized such that tensional deflection is<br />
restricted below 0.25 degree/m length. Operational arrangement shall be essentially be<br />
made with bevel gear and head stock assembly for easy operation by one person.<br />
x) The intake structure shall be circular in shape and sizes of the same shall also be<br />
determined by the following conditions:<br />
RL of high flood level : 1577.00m<br />
RL of lowest water level : 1562.00m<br />
In order to keep the operating floor free from obstruction and pipe work,<br />
delivery is to be taken below the pump floor level i.e. at RL 1583.20m, 2.40m<br />
below the pump floor level which is at RL 1585.60m and 8.6m above the high<br />
flood level in keeping the same level with the existing intake structure<br />
The depth of the Intake well is to be considered taking into consideration the<br />
minimum water depth required upto minimum WL to satisfy NPSHR for VT<br />
Pump to avoid air entry during drawdown.<br />
Provision for prevention of vortex formation.<br />
Provision for obtaining uniform distribution of the in-flow to all the operating<br />
pumps and to prevent starvation of any pump.<br />
16.5 For design of intake pump house. The following factors are to be<br />
considered:<br />
i) The pump house shall be square and shall be constructed above the Intake well.<br />
The floor of Pump House and discharge pipe floor with RCC beams shall be constructed to<br />
withstand the load of 6 (six) numbers of Pumps, Motors, Column Pipes, Delivery Pipes,<br />
Valves and other electrical accessories, H.O.T. crane etc. as well as part of the load coming<br />
from the Approach steel bridge which shall rest on the floor at one end. The pump floor<br />
and RCC beams shall be M-25 concrete and HYSD/TMT bars (Fe - 415). The walls of the<br />
Pump House shall be 250 mm thick 1 st class brickwork with 1:4 cement mortar (1cement<br />
and 4 sand). Adequate numbers of RCC columns along the centre line of periphery of the<br />
DTS : Detailed Tender Specification. Page 159