I've developed an improvement to the double-slit method, focusing on safety, in-game speed, and minimizing cancellation spam. This procedure will cut through any depth of aquifer in a 5x5 tube, using only dwarf-power.
Embark- 1-2 proficient Carpenters
- 1-2 proficient Masons
Your preference for carpenters vs masons depends on whether you plan on making the pumps with wood blocks or stone blocks. Stone blocks are cheaper; wood blocks are faster.
There's no reason to put points into Pump Operating. The total pumping time in any given phase is very short.
- Extra wood and stone. The minimal, most economical embark purchase to cover a typical project with two soil aquifer layers is 20 stone for blocks and 24 wood for grates, pipes, and corkscrews, totalling 135 points.
If your goal is in-game speed, then plan on your floors and pumps being made of 20 wood blocks. So your embark purchase for the aquifer would be 15 stone and 44 wood for 177 points.
These figures for wood and stone only cover the aquifer project. You'll need more wood and stone for beds, workshops, furniture, etc. And some materials may be available on site, depending on where you embark.
A seven-man expedition can break the aquifer fairly efficiently from the very beginning, but only if they aren't doing much of anything else. Farming, in particular, is a constant drain on your labor pool that you may want to avoid until the aquifer project is finished, or migrants arrive.
Materials- 4 Pipe Sections
- 4 Enormous Corkscrews
- 16 Grates
- 80 Blocks for pumps (4), walls (60), and floors (16)
This assumes that your aquifer has no more than two soil layers, which seems to be common. If you want to be extra prepared, then add 20 blocks per additional soil layer that you anticipate. If your aquifer goes into stone layers, then those layers will give you enough stone to produce more blocks than you're consuming.
Examine the AquiferHave your game set to pause on discovering damp stone. Designate a 1x1 u/d staircase deep down into the ground. When your miners uncover the top layer of the aquifer, the game will cancel the dig into that layer and pause on a damp stone warning.
You've uncovered the aquifer's top layer. Now it's important to determine if the top layer is also the bottom layer, meaning that the aquifer is only one layer thick. So re-designate two adjacent u/d staircases in the top aquifer layer, while deleting the designation in the layer below.
As your miner digs out a square in the top aquifer layer, the game will pause on another damp stone warning. Leave the game paused and examine [k] the newly revealed square in the next layer down. If it's dry, then you're dealing with a simple one-layer aquifer and you can skip down to the bottom layer procedure. If it's damp, then prepare your camp and begin the top layer procedure.
Prepare Your CampDig a 5x5 cross of down staircases two layers above the aquifer's top layer. Center the cross on the exploratory shaft that you just dug. Then dig a 5x5 square of u/d stairs one layer above the aquifer's top layer, as your first working area.
Arrange some stockpiles around the cross for your pipes, screws, grates, and blocks. Make sure that the stockpiles are big enough to always have excess space, so that loose parts in the pit will automatically get picked up.
Top Layer ProcedureThe top layer of the aquifer is a little bit easier and safer than the middle layers, because you can dig and deepen each side drain one at a time.
1. Confirm Starting Position. Start with a working area: a 5x5 box of u/d stairs just above the top aquifer layer.
2. Dig Central Drain. Dig a small cross of u/d stairs in the layer below your working area.
3. Side-Center Stairs. Dig four u/d stairs in the middle of each side of the working area. Then extend those stairs down a level.
4. Construct Floors. Construct 16 floors on the working space in the pattern shown. Use blocks; they're faster.
5. Channel a Side Drain. Pick any side of the square and channel out that side, except for the center stairs.
6. Build Grates. Build floor grates over the channeled holes. They will protect your dwarves without blocking the pumps.
7. Build Pumps. Build four pumps that will pull water out of the side drain, through the grate, and into the working area.
8. Run Pumps. Start all four pumps. Your pumpers should stay perfectly dry, and the side drain should be safe for your miners to enter.
9. Ramps to Stairs. At the bottom of the side drain, turn the four ramps into four down stairs. Do not touch the center-side stairs.
10. Deepen the Side Drain. Designate a 1x5 line of u/d stairs below the side drain, two layers below your working area.
11. Test the Aquifer. Once per z-level, you need to peek at the layer three steps below your working area, to see if you've found the bottom of the aquifer.
When deepening a drain in step 10, add 1x5 u/d stairs adjacent to the 1x5 line, on tiles not yet known to be damp. This extra line of designations exists solely to pause the game at the right moment. The first tile dug in the side drain will cause a damp stone warning and pause the game, so that you can examine [k] the newly revealed tile on the unexplored layer.
If the new layer is dry, then make a note of it. You'll be done soon. Otherwise, keep grinding.
12. Stop the Pumps.
13. Plug the Center-Side. Construct a wall in the center-side of the newly deepened drain.
14. Remove the Pumps. Wait for all the pump parts to be carried up to their stockpiles. If you skip ahead, the pump parts can scatter out onto the grates, and then fall into the drain.
15. Replace the Grates with Walls. But do it carefully. This is the most dangerous step. Make sure that there's no water sloshing around. Never remove two adjacent grates at the same time.
16. Loop. Go back to step 5 and do it all over again, until you've covered all four sides of the box.
17. Deconstruct the Floor. This takes some time, because deconstruction is slow. At least you get your 16 blocks back.
18. Dig out the New Layer. Dig u/d stairs in the rest of the 5x5 square below your work area.
19. Decision Point. Now you must remember what you learned in step 11. If your aquifer is only two layers deep, then skip to the bottom layer procedure. Otherwise, go to the middle layer procedure.
Middle Layer Procedure1. Confirm Starting Position.
2. Dig Central Drain. Dig a small cross of five u/d stairs in the center of the box, just below the working layer.
3. Construct Floors. Construct 16 floors on the working space in the pattern shown. Use blocks; they're faster.
4. Channel Side Drains. Channel out 16 tiles along the sides of the square. Do not channel the u/d stairs in the side-center. For safety, do not channel adjacent tiles at the same time.
5. Build Grates. Safety first! Cover all those dangerous gaping holes with your 16 floor grates, before the water starts flowing.
6. Build Pumps. Build four pumps along one side of the square, skipping the side-center. Orient them to pump through the grates.
7. Run Pumps. Wait until all four pumps are active. The water should not reach the pumpers.
8. Deepen the Side Drain. Designate a 1x5 line of u/d stairs below the side drain, two layers below your working area.
Your miners may experience some job cancellation, especially on the first deepened drain of each z-level. The other drains on that level will be easier, because some of the water will already be draining away.
9. Test the Aquifer. Once per z-level, you need to peek at the layer three steps below your working area, to see if you've found the bottom of the aquifer.
When deepening a drain in step 8, add 1x5 u/d stairs adjacent to the 1x5 line, on tiles not yet known to be damp. This extra line of designations exists solely to pause the game at the right moment. The first tile dug in the side drain will cause a damp stone warning and pause the game, so that you can examine [k] the newly revealed tile on the unexplored layer.
If the new layer is dry, then make a note of it. You'll be done soon. Otherwise, keep grinding.
10. Stop the Pumps.
11. Plug the Center-Side. Construct a wall in the center-side of the newly deepened drain.
12. Remove the Pumps. Wait for all the pump parts to be carried up to their stockpiles. If you skip ahead, the pump parts can scatter out onto the grates, and then fall into the drain.
13. Replace the Grates with Walls. But do it carefully. This is the most dangerous step. Make sure that there's no water sloshing around. Never remove two adjacent grates at the same time. Some mist may billow up after you remove a grate; that's normal.
14. Loop. Go back to step 6 and do it all over again, until you've covered all four sides of the box. The drain-deepening step will get easier with each loop as the sides start to drain from each other.
15. Deconstruct the Floor. This is the slowest step in the cycle, especially if you only have seven dwarves. At least you get your 16 blocks back.
16. Dig out the New Layer. Dig u/d stairs in the rest of the 5x5 square below your work area. This step generates some excess water sloshing around.
If you're digging into a stone layer and there's stone sitting on top of the side drains, then that stone will become pathable as the miners start digging. Hauling dwarves may walk into the turbulent water trying to retrieve the stone. If you want to be extra-cautious, forbid those stones before the miners start digging.
17. Decision Point. Now you must remember what you learned in step 9. If your new working area is the bottom layer of the aquifer, then go to the bottom layer procedure. If the layer below your new working area is more aquifer, then repeat the middle layer procedure.
Bottom Layer ProcedureAfter all that work, the finale is quite simple. But stay on guard. One false move here could ruin the whole project.
1. Confirm Starting Position. Your working area should be one z-level above the bottom aquifer layer.
2. Dig Center Tile. Just below the working level, dig an u/d staircase in the one tile in the center of the 5x5 square. That tile will be your exit.
3. Channel a Diamond. Channel the four tiles that orthogonally touch the center tile.
4. Construct Floors. Build them in a spiral pattern around the center, as shown.
5. Build Pumps. The pumps should drain from the center, dumping into the sides.
6. Operate Pumps. They should dump directly into the side drains, with no mess on the working level.
7. Construct Walls. Seal off the center tile by constructing walls on four sides of it. You might get cancellation messages and need to un-suspend the construction a few times.
8. Leave the Aquifer. Dig u/d stairs down two z-levels from the center tile. Don't dig sideways on the first dry layer, or it'll flood from above. Dig down to the second dry layer, and then you can expand.
9. Expand. Aquifers are easy once you get below them. Find the first cavern, build a drain, and dig up into the aquifer however you want.