📐 Underdrains (Block Lateral Orifice Headloss <6" WC, Uniform Air/Water Distribution)

Filter Underdrain Lateral & Orifice Calculator

Size high-density polyethylene dual-parallel lateral underdrain blocks (Leopold Type S / XA / AWI Wheeler) supporting direct media retention without gravel layers: calculate orifice discharge hydraulics, maintain uniform backwash distribution variance (<+/-5%), keep lateral hydraulic headloss below 6 inches WC, and underdrain profits.

1. Project & Operating Inputs

Filter Basin Floor Area (Sq Ft e.g. 500 Sq Ft Filter Floor)

Peak Combined Backwash Flow (GPM e.g. 10,000 GPM Water Wash)

Customer Bid Price for Supplied & Anchored Underdrain Floor ($)

Leopold HDPE Underdrain Blocks, Stainless Hold-Down Anchors, Grout ($)

2. Financial Breakdown & Yield

LEOPOLD UNDERDRAIN BLOCKS

Turnkey Underdrain Block Replacement Profit

Water Utility Mechanical Rehabilitation Margin

0.0%

Gross Revenue / Bill

Total Project CapEx

Operating / Direct Cost