40d:Floodgate

A floodgate is an object used to regulate the flow of fluids, such as water and magma. A wood, stone or metal floodgate will suffice for water flow, but only magma-safe materials with a melting point higher than about 1200°C, such as bauxite, steel or raw adamantine (don't do that) will hold back magma. Floodgates function much like doors with the 'Forbidden' option set at all times. Floodgates generally have to be built prior to flooding (obvious for magma, isn't it?) but can still be built at a water level of 1/7.

Floodgates have to be linked to levers or pressure plates to allow them to be opened and closed remotely. An open floodgate also can be walked through, whereas a closed one can not.

For example, a water floodgate connected to a river can be opened to create a shallow pool, then closed, the pool then be drained or allowed to evaporate. The resulting mud can be used for underground farms. Standing water can be used for drinking, or sufficiently rushing water used as a defense against invaders.

If there is no roof above a floodgate, and water comes to it from a source with higher elevation, the water can spill over it.

If a magma floodgate is opened, the magma will flow over it and melt any non-magma-safe mechanism, thus breaking the open/close trigger. Using magma-safe mechanisms will prevent this from happening.

The floodgate can also be used to cover fortifications when they are not being used. This will prevent enemies from firing into your fort through the fortifications, and can be useful if your marksdwarfs arrive at the fortification one at a time.

Unlike doors, floodgates can be built directly adjacent to each other; that is, floodgates do not require an adjacent wall. This allows channels wider than two squares to be regulated. This characteristic also permits for the construction of "siege doors", allowing areas wider than two tiles to be sealed off from the enemy. For instance, the three tile wide access point for a Trade Depot within the fortress can be closed down into a chokepoint with floodgates and a lever, giving your marksdwarves more of a chance to shoot invaders.

V · T · E Buildings
Workshops • Furnaces
Rooms	Barracks • Bedroom • Dining room • Jail • Meeting hall • Office • Sculpture garden • Tomb • Zoo
Furniture	Animal trap • Anvil • Armor stand • Bed • Bin • Bucket • Cabinet • Cage • Coffin • Container • Restraint • Seat • Statue • Table • Weapon rack
Access	Door • Floodgate • Bars • Grate • Floor hatch • Bridge • Road • Window
Constructions	Fortification • Floor • Stairs • Ramp • Wall
Machine & Trap parts	Axle • Gear assembly • Millstone • Screw pump • Water wheel • Windmill • Lever • Pressure plate • Trap • Support
Other Buildings	Archery target • Kennel • Shop • Siege engine • Trade depot • Wagon • Well
Related Articles	Design strategies • Bedroom design • Cave-in • Computing • Furniture industry