Controls at a glance
Keyboard
Arrow keys move the gold cursor, Space or Enter turns the pipe under it clockwise. U undoes the last turn, H gives a hint, P pauses and R starts a new board.
Touch screen
Tap a pipe to turn it a quarter turn clockwise. Use the Undo and Hint buttons under the board. The page never scrolls while you tap on the board.
How to play Water Flow
Water Flow is a pipe puzzle played on a square board of sandstone tiles. One tile holds a stone spring full of water, and one or more tiles hold a dry oasis with a palm tree. Every other tile carries a piece of copper pipe: a straight, an elbow, a tee, a cross or a short dead end. Tap or click a pipe to turn it a quarter turn clockwise. Your goal is to turn the pipes so that one connected run of pipe leads from the spring to every oasis on the board.
Water fills every pipe that is joined to the spring as you play, so you can always see how far it reaches. Two pipes only join when both of them open towards each other. The spring and the oases never turn: they show you where the water starts and where it has to go. When the last oasis fills, the water runs through the whole network from the spring outwards and the puzzle is solved.
Board sizes, stars and the daily puzzle
- 5x5: one oasis, a gentle start.
- 6x6 and 7x7: two oases fed by branching pipes.
- 8x8 and 9x9: three oases and long winding runs.
Every board is built by laying a full network of pipes first and then turning the tiles at random, so every puzzle has at least one solution. Stars compare your number of turns with the fewest turns needed for that board: match it for three stars, stay close for two. Using a hint caps the run at two stars. Your best result is saved for each size. Daily mode gives everyone the same board for each size today, and after a win you can challenge a friend with a link to exactly your board.
Tips and strategy
- Start at the fixed tiles. The spring and every oasis only open one way, so the pipe next to them often has a single correct position.
- Work from the edges. A pipe on the border cannot point off the board in a useful way, which rules out several positions at once.
- Read the shapes. A straight has only two positions, a cross never needs turning, and an elbow or tee has four.
- Follow the water. Extend the wet part of the network one tile at a time instead of turning random pipes far away.
- Count your turns. Three taps on the same pipe equal one turn the other way, so plan before you tap if you want three stars.
Frequently asked questions
Can every Water Flow board be solved?
Yes. Each board is made by laying a complete pipe network from the spring and only then turning the tiles, so turning them back always connects every oasis.
Do I have to use every pipe?
No. You win as soon as water reaches every oasis. Pipes that are not on the way can point anywhere.
What does the hint do?
A hint turns one wrongly placed pipe on the way to an oasis into the right position. It is free to use, but a run with hints earns at most two stars.
How are stars worked out?
Each board knows the fewest turns needed to fix its pipes. Finish in that many turns or fewer for three stars, within about one and a half times as many for two, otherwise one.
Is there a time limit?
No. The clock only records your time and stops while the game is paused. Take as long as you like.
