Risley Moss peat accumulation filled the depression, allowing colonisation by bog mosses such as the "Sphagnum" varieties, thus giving rise to the name "moss". Risley Moss is one of only two mosses in Cheshire where the water level has been deliberately raised in an attempt to encourage the regeneration of an active bog surface. The long-term restoration project to re-wet the moss began in 1978 and was completed in 2002. This scheme was undertaken to create a series of scrapes and bunds to retain water and recreate the perfect conditions for bog flora such as cotton grass and sphagnum mosses to re-colonise
Portlethen Moss lower elevations in every direction. Due to the high winds, moderate precipitation and cool temperatures that generally prevail, conditions are favourable for formation of an acid bog, since water stagnates, but eventually evaporates with ensuing acidity enhancement of decaying organic matter. There was virtually no drainage outlet in prehistoric times, and little drainage even in modern times. Many coastal mosses were initiated by the process of glaciation, which sheared rock formations to a generally level terrain, while also gouging moderate sized craters that would pond. This description fits the fundamental situation of Portlethen Moss, where sphagnum would have flourished over