Water Sieve

The Water Sieve is a refinement building that converts Polluted Water into Water by consuming Sand as a filtration medium, with Polluted Dirt produced as waste. Because Water is one of the colony’s most important resources, the Water Sieve is a key part of any settlement that wants to reclaim and reuse waste water instead of constantly relying on fresh sources. It is especially useful for supporting buildings such as the Lavatory and Carbon Skimmer without consuming clean Water, and it becomes important once a colony starts tapping Polluted Water from other biomes.

The building does not destroy germs. Any germs present in the input liquid are passed into both the output Water and the solid waste, so filtered water can still carry contamination. This makes it unsafe to assume that the Water Sieve produces clean, germ-free water for food preparation or other sensitive uses. If polluted and clean water streams are handled separately, germs can spread through the sieve and contaminate later batches, so water sanitation still needs to be managed carefully.

A constantly running Water Sieve can process up to 3 tons of water per cycle, which is enough for 300 Lavatory and Sink uses or 100 Shower uses. In practical colony layouts, this means a single sieve can support a large amount of bathroom and washing infrastructure if it is supplied continuously. Two Water Sieves are needed to pollute a full pipe of Water, one sieve can filter the output of five active Carbon Skimmers, and two Compost piles are needed to purify the Sand from one active sieve.

• If the Water Sieve runs out of Polluted Dirt, it stops receiving liquid from its intake pipe.
• It can accept Polluted Water, Salt Water, and Brine without taking damage, and these liquids do not change its temperature.
• The Sand output can become a logistical burden, since the sieve produces waste that must be handled or composted.
• A colony exploring wet biomes can use the Water Sieve to turn discovered Polluted Water into a more useful resource stream, provided the germ issue is accounted for.