An evaporative cooling system includes a primary cooling unit that utilizes a cooling fluid flowing through a primary heat exchange medium to cool supply air flowing past the primary heat exchange medium, a bleed line and a secondary cooling unit disposed upstream of the primary cooling unit with respect to a flow direction of the supply air. The primary cooling unit includes a supply line for supplying the cooling fluid to the primary heat exchange medium, a reservoir for collecting the cooling fluid supplied to the primary heat exchange medium, and a pump for recirculating the cooling fluid collected in the reservoir back to the supply line. The bleed line bleeds a portion of the recirculating cooling fluid from the primary cooling unit. The secondary cooling unit includes a secondary heat exchange medium that receives the cooling fluid bled from the primary cooling unit through the bleed line.