A water butt that stains the path is usually the tap
I noticed a green stripe on the slab under the water butt in October. The barrel looked sound. The path was slimy. I thought the plastic had split. I dried the side with a rag and watched. A bead formed at the tap thread, ran down the boss, and dripped. The washer inside the tap was flat, and the thread into the barrel was weeping. I had been topping the butt up from the downpipe all month and feeding the path.
A water butt stores rain. The tap is the only hole you open on purpose. It threads into a boss near the bottom so you can fill a can. A washer or a gasket seals that thread. Another small washer lives in the tap itself. If either goes, you get a drip you blame on the barrel. The barrel was holding water. The tap was not.
Hose fittings leak at the washer, not the hose is the same fault at the outdoor tap. I have replaced a hose for a perished ring. I have also stared at a stained slab and thought about a new butt. Look at the thread first. Dry it. See where the water starts. If it starts at the handle, the tap washer is gone. If it starts at the barrel, the boss seal is gone. If it starts at a crack in the plastic around the hole, you have overtightened a cheap fitting and the boss is finished.
I would not crank a plastic tap until it stops dripping. That is how the boss splits. Tighten until it seats, then a little more, not until your wrist hurts. Some butts have a nut and washer on the inside. Empty enough to reach in, or wait until you can, and check that nut has not walked. A thread with no inside nut is only biting thin wall. That is a drip waiting.
A downpipe that misses the butt is usually the outlet is the water that never arrives. This note is the water that arrives and then leaves by the tap. If the pipe is dry and the wall is wet, go to the outlet. If the barrel is full and the path is green, stay with the tap.
A watering can still earns its hook next to a hose. You fill it here. If the tap sits too low, you cannot get the can under it, so you tilt and splash, and the path stains even when the tap is sound. A stand or a pair of blocks that leaves can-height under the spout is hardware, not a flourish. Two cans of a size I can lift beat a puddle I step in every dry evening.
A compost bin is a box, not a bag of compost. I would not site the butt so the drip runs under the bay. You get a wet heap you did not plan and a stain you cannot sweep. Move the drip, or move the bin.
Skip a tap with no spare washer and no thread size on the pack. Skip PTFE tape as the only fix on a cracked boss. Tape will not close a split. Skip leaving the tap dripping "for the birds" all winter. A slow leak in a frost is a split tap by morning, and then you have a flood. Take the tap off before a hard freeze if it is the sort that holds water in the body, or at least leave it open so it cannot freeze shut and burst. Skip a second-hand tap from a crate of odds that almost fits. Almost is a drip.
This shows in autumn, when the butt is filling and you finally see the stripe, and in winter if a frost takes the tap. Summer is when you notice because you are at the can every evening. I now wipe the boss on a wet Sunday in October and watch for a bead. If it forms, I change the washer before I buy a barrel.
I do not need a new butt because the path stained. I need a tap that seals at the thread, and a can that fits under it.
If I later add a buy link here, it will be a paid promo.