Kulmala wetland creation, Ruovesi

LIFE+ Return of Rural WetlandsFinland, Ruovesi, Kulmala wetland creation

Wetland area before creation 2011

Photo: Juha Kuukka

Photo: Timo Niemelä

The aims and premises of Kulmala

wetland creation

The aims of the wetland creation:

� To develop model wetland of waterfowl habitat

� To increase biodivrsity in an agricultural area

� To improve water protection

The premises of wetland creation:

� The wetland will be constructed on land owned by the private

� The soil in the area is erosion sensitive, like fine sand and silt

� The catchment area is about 200 hectares and mainly ditched

� It is possible to create the wetland mainly by damming but also digging

will be used to increase the area size

Embankment construction• The base (footprint) of the embankment was cleared of any organic matter prior

to construction


Installing water control structure

• Full-round flashboard riser made from HDPE (high-density polyethylene) pipe wasinstalled to control water levels and dewater the wetland

• The riser was installed within the existing drainage canal system

• Beavers or muskrats are not present here, so they don´t cause any problems


HDPE (or ”PE-HD”) fullround flasboard riser

• For pond and wetland water level control

• All joints is important to do with stainless steel screws, mainhole can be locked

• Increase – decrease style of incremental movable boards

Kuva: Timo Niemelä

The costs of the riser:

• diameter 800 mm, height 3000 mm: 1000

€, incl. tax

• inlet and outlet pipes: 560/500 mm SN8

plastic pipes, and other supplies 1 000 €,

incl. tax

• The riser was placed in embankment where the openings and access hatch can be

accessed from shore


Installing water control structure

• The emergency spillway was constructed to provide an escape for excess water above the

designed level


Construction of the emergency spillway with stoplogs

• A rocky emergency spillway was designed about 50 cm lower than the settled top of the embankment

• 200 tons of rock were transported to the spillway, costs about 1 050 € (rocks) and 550 € (transporting)

Photos: Timo Niemelä

Construction of the emergency spillway…

• Stop-log system (”wooden wall”) was built of planks size 42 mm thickness x 145 mm width



• Stop-log water control structure can be used to regulate water level



Embankment construction…

• The embankment was constructed with soil excavated from wetland area

• Soil transporting was done as a voluntary work by the landowner

Kuva: Timo Niemelä Photo: Timo Niemelä

Patopenkereen rakentaminen

Kuva: Timo Niemelä Kuva: Timo Niemelä

• Fill materials was put in lifts about 20-50 cm thick and compacted it by running over the

entire surface with the excavator

• The top of the embankment was built 50 cm higher than designed water level

• The embankment with 1:2 side slopes is enough because suitable grass–cutting machines

are used for side slopes maintanance by the landowner

Summary of the construction works

• The embankment: length 190 m, top width 3,5 m, mean height 1,4 m

• Total costs of the construction works: 63 working hours x 73,80 €/ h = 4649 €, incl. tax

• The excavator: Hitachi Zaxis 210 LC equipped with rototilt head


Construction of artificial islands and

other excavation work to increase biodiversity


• Some artificial islands and other resting places were done for waterfowl, also deeper ponds

to create microhabitats for fauna was excavated

• Total costs of these excavation work: 24 working hours x 73,80 €/ h = 1770 €, incl. tax

Kuva: Timo Niemelä

Kuva: Timo Niemelä

Kulmala wetland, total area of 1,3 hectares is favored wetland

for waterfowl like dubbling ducks

Photo: Juha Kuukka

Kulmala wetland 4.7.2015

Photo: Marko Muuttola

Kulmala wetland 4.7.2015

Photo: Marko Muuttola

Kulmala wetland creation, Ruovesi

Environment