Question 1

Is it legal to collect rainwater?

Accepted Answer

It depends on your state. Most states allow residential rainwater collection with no restrictions. A few western states (Colorado, Utah, parts of Arizona) have historically limited collection due to water rights laws, though most have since relaxed restrictions for small household use. Colorado now allows up to 110 gallons (two 55-gallon barrels). Check your state's specific rules before installing a large system, but for most homesteaders, a 50-100 gallon barrel is legal everywhere in the US.

Question 2

How much water does a garden need?

Accepted Answer

A typical vegetable garden needs about 1 inch of water per week, which equals about 0.6 gallons per square foot. A 100 sq ft garden needs roughly 60 gallons per week during the growing season. A single 50-gallon barrel will water a 100 sq ft garden for less than a week. For meaningful water independence, plan on 150-500 gallons of storage capacity depending on garden size and how dry your summers are.

Question 3

How do I keep mosquitoes out of my rain barrel?

Accepted Answer

Three strategies work: (1) Make sure the lid and overflow opening are fully sealed with fine mesh screening — mosquitoes need still water to breed, and they need to get into the barrel first. (2) Add a tablespoon of vegetable oil to the water — it creates a thin film that prevents mosquito larvae from breathing. (3) Use Bacillus thuringiensis israelensis (Bti) dunks, which are non-toxic to plants, animals, and humans but kill mosquito larvae. Most quality barrels come with built-in fine-mesh screens on the inlet.

Question 4

How do I connect rain barrels together?

Accepted Answer

Most systems use an overflow port on the first barrel connected to the inlet of the second. When the first barrel fills, water overflows through a hose into the second. For a pressurized linked system (better flow rate), use bulkhead fittings to connect barrels at the bottom — this equalizes water level across all barrels and draws from all simultaneously. The BlueBarrel system provides all the hardware for this type of installation.

Question 5

What size rain barrel do I need?

Accepted Answer

For occasional garden watering: 50 gallons is fine. For a household that relies on rainwater for most garden irrigation: 150-200 gallons minimum. For a homestead with a serious water independence goal: 500+ gallons (typically achieved by linking multiple barrels or using IBC totes). Rule of thumb: a 1,000 sq ft roof collects about 560 gallons per inch of rainfall. If you get 1 inch of rain per week, you could theoretically fill 11 fifty-gallon barrels every week — the limiting factor is usually storage capacity, not rainfall.

Feature	Downspout Diverter	Direct Downspout Cut
How it works	Insert diverter into downspout — redirects flow to barrel when open	Cut downspout, redirect into barrel top inlet directly
Cost	$20-$40 for diverter kit	$5-$10 in downspout extension + screen
Overflow handling	Automatic — excess water flows down original downspout	Requires overflow port on barrel or manual management
Gutter compatibility	Works with most 2x3 and 3x4 inch downspouts	Works with any downspout — just measure and cut
Best for	Beginners who want easy installation and overflow protection	DIY builders who want maximum capture rate

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