kiipu wetland construction jokioinen finland

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Paintings Jari Kostet, MKJ Pictures: Mikko Alhainen, Juha Suonpää

Life+ Return of Rural Wetlands

Kiipu Wetlands, Jokioinen

The objectives of Kiipu wetlands

• The objectives are to – Improve the water quality of lake Kiipunjärvi by binding sediments and nutrients from drainage

waters – Create habitat for wetland fauna, in particular waterfowl – Promote biodiversity, landscape values and multifunctional land use – Act as demonstrative site of wetland work in the region

• Background

– Kiipu wetlands are divided to three different basins stretching to properties of two landowners • Two basins are built by excavation and one by combining excavation and damming the water to a higher level. • The former land use has been low quality agricultural land and waterlogged marshland.

– The catchment area is 600 hectares, divided to two sections • Larger catchment area dominated by clay fields and intensive agriculture • Smaller catchment area dominated by peatlands, moraine and intensive forestry

– The wetland project was done in co-operation with the local lake association Kiipunjärven suojeluyhdistys KIPSU ry, dedicated to improve the water quality and recreational values of the lake.

• Sincere thanks to Juha Suonpää, Ilkka Järvi and all the voluntary participants of the lake association • Sincere thanks to the landowners and the farmer of the area: Anja and Lauri Koskenoja, Kari Eskola and

Metsähallitus.

Kiipu wetlands

3.

2. 1.

© Maanmittauslaitos, lupa nro 326/MML/11 Pohjakartta © Maanmittauslaitos lupanro 326/MML/11

The address of the notice board is Kiipunjärventie 417 Jokioinen More information and site presentations in field (in finnish) Juha Suonpää 0400-476754 Ilkka Järvi 0400-307769

Annual algal blooms and low water quality needed action. Wetlands are one possibility the decrease the eutrophication caused by

nutrient rich drainage waters.

Kuva Mikko Alhainen

30.6.2012, kuva Juha Suonpää

Wetland 1 • The wetland was built to low laying land. The starting point was very thick willow brush.

• The work started by tree and brush removal. The volunteers of KIPSU (lake association) cleared the brush and local forestry company transported the wood away from the upcoming wetland area. Metsähallitus logged area in its property.

30.6.2012 kuva Juha Suonpää

• Lunch break is an important part of the voluntary work day of the lake association. Volunteers cleared approximately 1 hectare of impenetrable thickets.

• Clearing of woods is almost done and the area is getting ready for excavation work.

• The telephone etc. cables in the areas were marked before the excavators arrived.

13.8.2012 kuva Mikko Alhainen


• Wetland excavation started August 22nd.


• The work was started with long bean excavator. • (Hyundai 210 7A equipped with 16,5 meter beam,)

• The soil was stable and carried the heavy machinery well.


• Work progressed well. An average of 50-60 cm layer of soil was removed creating water depths varying from 30-50 cm

• Excavated soil was dumped right next to the area and finished smoothly to be able to maintain the dump area with tractor mover in the future to prevent overgrowing by willow brush etc.


• The work of 1st day is done • Small areas were left unexcavated, and these spots

created small islands to spread water current to whole site and for waterfowl to rest.


• The work continued on the other side on the main ditch


• In this section largest amount of soil needed to be excavated. • Other machine with regular beam was taken to the site to

spread the excavated soil to the dump area.


• It is cost effective to have two machines working simultaneously

• Two machines works twice as fast less total time and supervision needed in field

• The cost of regular beam machine is half of that of long beam regular beam can work with soil a lot cheaper

• Long beam is needed for the effective excavation of areas inaccessible for regular beam machine


• At the upcoming outlet of the wetland a small area of bruch was still on the way. Local landowner and active member of KIPSU Juha Suonpää took his saw out and cleared the brush in hot summer weather.


24.8.2012

• The dump area was formed to very low slopes. Level and smooth area is easy to keep open with tractor mover. Without regular moving the just opened lake view from nearby road will be soon lost behind fast growing brush

• Third day of excavation • The last section adjacent to lake shore was dug in rather untouched soil. With temporarily unexcavated

areas the wetland bottom could be kept dry during the work excavating dry soil is lot easier and cheaper than digging with water everywhere.

• Next to the lake soil was softer and excavator had to work from supporting boards

• To be able to excavate part of the area dry made the work significantly faster • The bottom soil in the area was very hard compressed clay, you need to jump to make a footprint to the clay • The softer surface soil was a narrow stretch right next to the lake.



• Once an a while the clay was stuck to the scoop • The old outlet to the lake was filled. Low

embankment wide enough to maintain with tractor was built between the wetland and the lake

• The unexcavated ridges held the water back temporarily. It was good luck not to have heavy rain during the work.

• As the water current was stopped the disturbed water had some time to settle and the sediments to sink in the bottom before the last section was flooded.


• First wetland is done and outlet to the lake is opened. • The last section of the wetland was filled from the lake


• Water from lake filling the last part of the wetland that was excavated dry


• Outlet to the lake is open • The last temporary ridge is opened and the water

of the ditch can flow to the lake. • Only the part of the ridge above water level is

excavated and the bottom half will be left to work as submerged ridge stopping solid materials moved by bottom current.

Tähän 1 altaan faktat 22.8.2012 kuva Mikko Alhainen Wetland 1 before…

…and after 24.8.2012 kuva Mikko Alhainen

Wetland 2 • The second wetland basin was built on low-laying waterlogged agricultural land • The work was started by removing trees and brushes from dump and embankment areas

around the wetland.


• First the overflow dam was constructed • During the floods large amount of water are moving due to the

600 hectare catchment area. The durability of the dam was strengthened with heavy plywood heart.

• The center board was assembled about 30 cm above the forthcomingg water level, so that the V-shape could be cut to the board with chain saw.

• The corners of the boards in each side were set at the same level with the upcoming embankment.


• Boards were set in the hole that was dug in the field • By assembling the dam in the corner of the field had several

benefits: • The structure could be built dry • Well compressed clay is stable and waterproof

foundation for the dam. • The whole wetland could be built before raising the

water level. The last thing to do was to close the old ditch channel and to let water rise until it started to run over the new dam.

27.8.2012 kuva Mikko Alhainen • The area around boards was filled and the clay compressed tight against the boards, using manpower at the corners and critical places.

• The shape of the dam was formed with clay

27.8.2012 kuva Mikko Alhainen • Farmer Kari Eskola and active volunteer of KIPSU Juha Suonpää

discussing about wetland construction


• V-shape was cut to the board.


• The clay dam was carefully covered with cloth used for road construction

• The purpose of the cloth is to prevent direct erosion of water to the clay structure.


• The cloth was also set to upstream side of the dam • The whole structure was covered with rocks from 60-200 mm

28.8.2012 kuva Mikko Alhainen • The dam is almost done and the construction of embankments and deeper areas has started.

28.8.2012 kuva Mikko Alhainen • Between the wetland and the road an embankment was built to keep the road dry and to be able to dam the water to a higher level

• It is crucial to remove all the loose surface soil beneath the embankment. If any loose soil is left, the structure will most probably leak between bottom soil and built structure.


• Contruction continues


• It is importantt to pay attention in places where structures built separately meet. • Here the last section of the embankment was built later, and the seam where the parts meet is potential

place for problems

28.8.2012 kuva Mikko Alhainen • The tile drainage outlet and well of the field was searched. • The structure was fixed to meet the upcoming water level and to take

care of the drainage of the fields in new situation

28.8.2012 kuva Mikko Alhainen • The excavated soil was dumped to adjacent field. • The soil raised the field surface and that compensated for the decreased

drainage depth of the remaining field


• Deeper area was excavated to the corner of the wetland where most water are coming in.


• In the centre of the wetland a submerged ridge was left. In practice in is an unexcavated strip of the field.

• The purpose is to cut off the bottom current that carries suspended solid materials and coarse particles. The ridge, just few cm below water surface, holds solid materials in the above deeper areas.

• Finally the old channel was plugged and water started to fill the basin. First the upstream half was filled, then the water flow over the ridge to fill the last deeper area above the dam


• When other structures were done, the dam was finished. • The rocks were set to right places and the corner of the channel

was covered with rocks to prevent erosion. • The direction of water flowing over the dam was directed away

from the road to prevent direct pressure and erosion of the road structures.


• Water is rising • In the lower picture the

differences in water quality of different catchment areas is clearly visible


• The embankment allows the water to rise to level very close to road surface without risking the durability of the road.

31.8.2012 kuva Mikko Alhainen • Water has filled the wetland

• The V-cut in the board was made too deep, and a 15 cm high strip of board was assembled to the dam to raise the water enough to cover the ridge across the wetland

31.10.2012 • Autumn 2012 was extremely rainy. • High floods rose all the way up touching the corner poles of the dam. The current also moved the

rocks right below the boards. There should have been bigger rocks in the critical places

3.12.2012

• In early December the waters went down and frost hardened the area for tractor to move.

• Juha Suonpää had collected bigger rocks from field edges

• The dam was fixed in comfortable -22 degree weather.

3.12.2012

• The supporting poles were cut short and the V-shape cut to lower angle to provide more space for flood waters

• The added 15-cm board was left, and small V-cut was made to prevent the dam from freezing, if the current goes down during long cold period.

Before…

…After

Wetland 3 • The basin was contructed by widening the existing channel • The deeper and wider channel can bing coarce depri of flood waters

Kesä 2011 Kuva Mikko Alhainen

• The excavated soil was used to fill a ditch that was causing difficulties to a local farmer. Filling the ditch can be described as compensation for the agricultural land used for wetland construction

Kesä 2011 Kuva Mikko Alhainen


• The brush was removed with long beam excavator • The basin was constructed to depth varying from20 cm to 1 meter • The drainage of the field was secured with drainage tile

• TÄHÄN KUVIA OJAN TÄYTÖSTÄ JA KAIVUSTA


• The excavated soil was hauled with tractors and dumped to old ditch channel

• Tractor work was done as voluntary work by local farmers: Juhana Eskola, Raimo Mattila, Santeri and Juha Suonpää.

30.1.2013 • The area works as small sedimentation basin

Costs of Kiipu wetlands Total area of 2 hectares, water surface ~ 1 hectare

• Rural Wetlands project – Excavation work etc 10 400 € – Materials for dam 700 € – Planning, suprvising of work 14 days TOTAL external assistance and materials

(for wetlands 1 & 2) 11 100 €

• Lake association Kiipunjärven suojeluyhdistys KIPSU ry

– Excavation 3 282,28 € (wetland 3) – Tile drainage work 1 302 € (wetland 3) – Materials for tiling 1 595 € (wetland 3) – Hauling of brush/timber 1230 € (all

places) – Voluntary work

• Working hours 202 • Working hours with man + tractor 43

– Catering for volunteers 234 € Total external assistance and materials ~7 650 €

• Metsähallitus – Logging of approximately 80 m3 of birch

Altogether – External assistance and materials ~ 19 000 € – Respectful amount of voluntary work, activity and participation of local

people and the lake association KIPSU! – Costs of tree removal of Metsähallitus – Planning and supervision costs of Rural Wetlands project

Ahlqvist Jari ja Helvi Kirveskallio Marko Rehumäki Markku Dahlman Kai Kirveskallio Mikko Rinne Pekka Dahlman Martin Kivistö Erkki Seppänen Osmo Tamminen-Dahlman Anne Koskela Leila Silvennoinen Kari Eskola Juhana Kuismanen Matti Silvennoinen Kari ky Asianajotsto Eskola Kari Leivo Matti ja Maija Simola Merja Eskola Matti Luoma Heikki ja Pirjo Suonpää Santeri Gabrielsson Paula Lähdekorpi Kauko Suonpää Antero ja Helena Harjula Lea Lähteenmäki Leo Suonpää Juha Harmaa Juha ja Terhi Maltari Arja Suonpää/Eerola Juha Jalasjoki Matti ja Tarja Mattila Paavo Valtti Seppo Järvi Anita ja Ilkka Mattila Raimo Veijalainen Jorma Kankaanranta-Suomi Erja Paara Antti Vesanen Heikki Kankare Tuula Pusa Pauli ja Tora Viher-Vehmas Pauli ja Tuula Kaseva Timo Ranta Kirsti Viitanen Hannu Kirveskallio Aleksi Rautionmaa Matti Vuohijoki Lasse Kirveskallio Jorma

Persons and organizations that supported the Kiipu Wetlands project with donations and/or voluntary work

Lake association KIPSU organized a fund raising campaign to cover the cost of the wetland. The association ‘sold’ machine working hours for wetland construction at 20€/hour The campaign was a success, and KIPSU received donations worth of 2 840 €

Future shows how wetland works for water protection and wetland habitat

Sincere thanks to all that participated the construction of

Kiipu wetlands

kiipu wetland construction jokioinen finland

Documents

kuva mikko alhainen

dump area

area dry

upcoming wetland area

lake soil

kuva juha suonp

smooth area

dry soil