One of the finest spring areas in Espoo is located in Pyykorpi in Nuuksio National Park on the northernmost tip of the city. It includes a valley basin with a 100-metres long quagmire with rare spring flora, a spring in a quagmire in a rock hollow and its streamlet, and several smaller springs and streams.
Many streams are fed by springs or mires with seepage effect in streambanks or beds. Springs make streamwater clearer and in many cases maintain their flow during dry season. Many of the Espoonjoki tributaries, in particular, are spring-fed. An even supply of cool, oxygen-rich water throughout the year contributes to the success of the Trout and the Common freshwater shrimp, among others.
Springs and their surroundings tend to remain unfrozen in winter, and are thus favoured by many rare plants and mosses. Several spring species are remnants of the post-ice age period. Demanding spring species in Espoo include the Dotted thyme-moss, the Fen peatmoss, the Alpine enchanter's nightshade, the Bog stitchwort, the Large bitter-cress and the Glyceria lithuanica. Fauna consists mainly of insects and small crustaceans.
From puddles to quagmires
Springs are classified into several types. Puddles are formed by ground water seeping through the soil and accumulating in a hollow. If there is excess water, a streamlet appears. Almost all of the remaining spring puddles in Espoo are located north of Ring Road III. The largest of them can be up to five metres in diameter.
Quagmires are soft boggy areas of land that give way underfoot. Sometimes ground water gushes up to the surface like a stream out of nowhere.
Springs turned into wells or destroyed by draining
The majority of springs in Espoo has been modified or completely destroyed by human activity. They have been dug and drained for agricultural or forestry purposes, or turned into wells. In the latter case, the spring can be helped by removing the well rings. Some of the lost spring assets are located in field or road side ditches, or have dried up when natural water flow has altered due to construction, for example. In some cases, tree felling has exposed a spring to sunlight and destroyed its vegetation.
Today, springs are protected under the Water Act and the Forest Act. Springs form habitats which are particularly important for forest diversity, and their natural state must be protected. Most springs in Espoo are small, contain small or moderate amount of water, and are far apart, making it very difficult for the demanding flora to spread from one location to the next. Therefore, the conservation of the remaining springs is of utmost importance. Springs continue to be destroyed by accident, however, during the piping of stream or drainage flows.
The springs in Espoo were listed in 2012. The mapping revealed 19 springs in natural state. Spring-fed steams are not included in this figure.