Dears Sirs. I'm from Panama, Panama. My firm is upgrading the potable water reserve and pumping station for a 400 rooms hotel. Tne new configuration calls for 4 ea. 15,000 gallons, horizontal installation, in line, 10 ft. diameter by 26 ft long. fabricated with steel plates. Tanks are located 60 ft above a 30,000 gallons underground concrete tanks. This is the tank used to collect the water from the city. So with a transfer pumps we replenish the 4 tanks with a level sensor that we are locating on a branch coming out of an equalizer line that connect the tanks from the bottom and extending above the top of the tanks. this line, open to atmosphere, with a screen to protect against insects. Ea. tanks has a gate valve before connect it to the equalizer header for service purposes. These tanks has a dual purpose: 30,000 gallons reserve for fire protection and 30,000 gallons for potable water. The new variable frecuency drive booster pumping station is located 3 feet below the bottom of the tanks but the existing fire pump is located 50 feet below tha tanks.
How can I arrange the suction piping of the tanks to the booster unit in order to pull the same amount of water at every moment and avoid stagnation? New regulations require control of the bacteria Legionella pneumophila. For the suction line to the fire pump I see no problem because I have a 10" equalizer header and connecting an 8" line to the suction of the pump and no require how they draw water from the tanks . Each tank has it's own vortex plate only on the branch to goes to the equalizer header.