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Most calcareous seepages are small and very localised features, although large expanses are present in some upland areas such as the Pennines. As well as a high base status that gives rise to travertine/ tufa deposits of encrusting calcium carbonate , the issuing water is also characterised by small temperature fluctuations and relatively low trophic status. They are often dominated by Cratoneuron moss carpets or mono-cultural standards of higher plants, though some can be botanically very rich and hold species such as Birdseye primrose.

Vegetation is often limited, although Carex spp may be well developed in some places. Dead wood is an important component of these seepages, as this is the medium for some crane fly larvae.

The channels are subject to change as a consequence of modifications naturally caused by erosion.

These can be seasonal ponds, the edges of larger water bodies or along the edges of lowland slow-flowing rivers. The drawdown zone left behind comprises of wet mud, algal scums and thin layers of vegetation, including detached tree leaves, twigs and other plant litter. These habitats are most often associated with floodplains, such as at the edges of pools and temporary water.

These plants may form large beds or can be part of a fringe of vegetation around the edge of pond and provide a terrestrial structural mosaic.