This Instructable describes how I made a rainwater collector completely from parts I've had in my house. The concept was to create a device that would collect and store rainwater for my garden in a container that would not become foul or easily breed insects. Also, I wanted something that was portable and easily concealed.

Rainwater has advantages over tap water. It has no chlorine. It is warmer than water coming out of the mains. And although in this case the amount of water diverted is small, preventing rainwater from running into the storm sewers helps to manage water flow, erosion and flooding. And finally, although the sums here are small, the water you collect is free.

This Rainwater Collector is made completely from upcycled parts and thus was at no cost to me. Rainbarrels can collect 40-50 gallons (eight to ten times more than this) but also will cost about 100 dollars including a water diverter.

Step 1: Materials and Tools

Materials

5 gallon plastic pail with a lid
16 inch plant saucer. Why the saucer? The greater the surface area of the collector, the more water you collect. A 16-inch saucer has 50.24 square inches of surface area. The lid itself has 37.68 square inches and that is an increase of 33%! With the addition of other containers to capture rain that you pour into the pail, you can collect five gallons in a single rainfall.
Old plumbing fixture. This is the part that would fit into a bathroom sink basin and go into the p trap
Silicone sealant
Washing machine lint filter (this was actually new but I have dozens of them)

Tools

Drill with 1 1/4 inch forstner bit

Step 2: Building Procedure

Drill thru the saucer and the top of the lid of the pail
Thread the plumbing fixture thru this hole and tighten the nut medium-tight. You don't want to crack the saucer. The best saucer would have a flat bottom but I used what I had
Seal both sides with silicone caulking.
Put a lint trap on the bottom to catch leaves and insects

Step 3: Using the Collector

I keep the collector behind the air conditioner. It's out of sight but still gets full access to the sky/rain
After it rains you will have water collected in the pail. Excess water will simply run off the device and be no different from the rain falling anyway.
I pour the water into a watering can but you could just pick it up by the handle and pour it on the garden.
I keep a couple of other plastic containers out and empty them into the rain collector. The only trick there is to not let water sit in the containers too long. It doesn't take mosquitos long to find it and breed.