Project data
Export to Open Know How Manifest
Device data
Page data
Part of WaterPod
Type Project, Device
Keywords Rainwater, water, rainwater catchment, rainwater collection, rainwater calculations
Sustainable Development Goals SDG03 Good health and well-being
Published by Lonny Grafman
Published 2009
License CC BY-SA 4.0
Location data
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Location New York

The WaterPod will be collecting rainwater from a few of the impermeable roof areas. The calculations for collection are on this spreadsheet. There are three tabs feeding the results:

  • Tab:Collection Calcs - Calculates the monthly availability of the rainwater.
  • Tab:Collections Dimensions - Calculates the available rainwater collection area based upon the planned structures.
  • Tab:Regional Climate Data - Show monthly rainfall from historical averages. Could be made more current.

Regional Climate Data[edit | edit source]

The historical 1971 - 2000 Rainfall Normals for Central Park, New York[1] are:

Jan Feb Mar Apr May Jun
3.42 3.27 4.08 4.2 4.42 3.67
Jul Aug Sep Oct Nov Dec
4.35 4.01 3.89 3.56 4.47 3.91
Annual
47.25

Basic Calculation[edit | edit source]

[math]\displaystyle{ Collection\ Volume (gal) = Rainfall\ (in) \times \frac{1 ft}{12 in}\times Collection\ Area\ (ft^2) \times \frac{7.48 gal}{ft^3} \times Roof\ Coefficient \times Efficiency }[/math]

or

[math]\displaystyle{ V=R \times A\times k \times e }[/math]

(in some cases the efficiency of the system is assumed to be 100% and therefore equal to 1, having no effect on the rest of the equation.)

Click here for more detailed rainwater collection calculations and explanations.

Conclusion[edit | edit source]

Wait until the spreadsheet is finalized before posting the final conclusions here.