RoofRainYield

Creve Coeur, MO rainwater: 33,652 gallons off a roof

How much rain a roof in Creve Coeur, MO collects

33,652gallons a year

That is a 1,500 sq ft asphalt roof under Creve Coeur, MO's normal 42.3 inches of rain, about 795 gallons for every inch that falls.

In Creve Coeur, MO a single barrel does most of the work. Storms come often enough that a small tank refills before it runs dry, and a bigger one would mostly sit full.

Rainfall: NOAA 1991-2020 climate normals, the St Charles 7 Ssw station (4.6 mi away). Creve Coeur, MO ranks 63rd wettest of the 80 cities covered in Missouri.

Month by month in Creve Coeur

MonthRain (in)Off the roof (gal)Garden shortfall (gal)
Jan2.562,035
Feb2.191,741
Mar3.592,853
Apr4.593,648
May5.224,149
Jun4.283,4029
Jul3.853,06062
Aug3.542,814101
Sep3.312,631130
Oct3.202,543143
Nov3.472,758
Dec2.542,019

May is the wettest month (5.22 in, 4,149 gal off the roof); Feb the driest (2.19 in). Garden shortfall is what a 200 sq ft vegetable bed needs beyond the rain that lands on it, April to October.

Which tank size is worth it in Creve Coeur

Best fit: one 55-gallon barrel, which delivers about 365 gallons to the garden in a normal year (82.0% of its need).

If you buy one, a 55-gallon barrel with a downspout diverter is the whole job. Check that the overflow points away from your foundation, because most of Creve Coeur's roof water will pass straight through it.

TankWater used (gal/yr)Spills over (gal/yr)
55 gal36532,192
110 gal36532,192
165 gal36532,192
275 gal36532,192
550 gal36532,192
1,000 gal36532,192
1,500 gal36532,192
2,500 gal36532,192
5,000 gal36532,192

Simulated storm by storm through a normal year using the station's count of days with 0.1 in or more of rain each month.

Is rainwater collection legal in Missouri?

No rainwater harvesting regulations

From the 2015 (Pacific Northwest National Laboratory report 24347); not yet re-checked against current law, so check with your state water agency before building anything large. Source