The second type of aquaculture is intensive—a system of artificial habitats that rely on feeding and filtration systems in order to function. Extensive aquaculture has little to no environmental impact, but requires large tracts of land and significant labor for harvesting. For this reason, it is reasonable to assume that areas like the Eastern shore (where land comes at a premium and labor is comparatively expensive) are unsuited to extensive aquaculture. In contrast, intensive fish farming can be performed in smaller areas and at greater densities, minimizing land and labor, but the environmental impacts of these techniques can be significant (fig. 25). Intensive aquaculture projects use upwards of a million gallons of water per acre (about 1 m³ of water per m²) each year. If this water is not treated and reused onsite, it can lead to significant environmental degradation.