17 DEC 2003
Additional calculations and design data will need to be assembled for a vari-
ety of equipment to support the filtration system. These items include but are not limited
to the following.
6-5.1.1 Pumps. Head loss calculations and power requirements are needed for back-
wash water supply pumps, spent backwash water pumps to transfer filtrate back to the
head of the plant, settled sludge removal pumps from the spent backwash holding ba-
sin, and filter feed pumps.
Air supply. This is necessary for valve operations and air scour if provided.
6-5.1.3 Tankage. Filter feed pump tank, filtered water storage, clean backwash water
storage, and spent backwash water storage all may be required.
6-5.1.4 Controls. Filter head loss rate, backwash sequence, flow rate, interlocks, and
alarms all may be required.
6-5.1.5 Chemical Feed. Chemical storage, mixing, day tank, and chemical feed
pump sizing, chemical selection, feed concentration, and physical storage are all con-
6-5.1.6 Access. Sample collection, monitoring, and maintenance of equipment all re-
quire some kind of access.
In addition to utility requirements, additional design and calculations related to
architectural and structural components will be required. These types of calculations are
application specific, and, therefore, no specific calculations are provided.