Drainage in Finland · Requirements of controlled drainage and subirrigation • Relatively high...

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Drainage in Finland

Helena Äijö

Field Drainage Association

17.5.2012, Tartu

Drainage

• In Finnish climate conditions drainage is essential requirement

for functional agriculture.

• Effective drainage enables full exploitation of the growing period

and affects positively on productiveness.

• Functional drainage concerns also forestry, infrastructure and

populated areas.

• New challenges related to drainage: climate change, changes in

legislation, changes in administrative resources and distribution

of work and responsibilities between different actors (for

example authority and private sector).

Drainage

• Basic drainage

dredging, embankment, pumping

• Field drainage

ditching and subsurface drainage

• Flood prevention

dredging, embankment, retention

Needs for drainage

Finland has:

• compact soils

• flat surface

• wet hydrological conditions

precipitation > evoporation, during spring and autumn

Kuva: Laura Alakukku

Hydrological Conditions

Basic Drainage

• Effective basic drainage is a necessary requirement for farm-

level drainage.

• In Finland, on going projects concern mainly restoration and

renovation of old drainage projects.

• In general, drainage plans are prepared by consultants.

• In certain cases (e.g. ditching procedure), the regional Centre for

Economic Development, Transport and the Environment may

prepare the drainage plan. This service is a liable to charge.

• During the drainage procedure water protection, fishery and

landscape needs should be taken into account.

Number and total area of basic drainage

projects during 1990-2009

0

2000

4000

6000

8000

10000

12000

0

100

200

300

400

500

600

700

800

900

1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

ha No.

Number of projects

Total area of basic drainage, ha

Subsidies granted to

basic drainage during 1998-2011

0

500

1000

1500

2000

2500

3000

0

10

20

30

40

50

60

70

80

90

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

k€ No.

Number of projects

Total amount of aid, 1000 €

Responsibilities in State support

• Regional Centre for Economic Development, Transport and the Environment:

– grants subsidies

– supervises implementation, maintenance and fulfillment of financial terms

– evaluates environmental perspective of the project (including fishery, landscape and water quality aspects)

• Finnish Agency for Rural Affairs:

– administers subsidies and subsidy payments

• Ministry of Agriculture and Forestry:

– definition of policies, general management

• Changes in financial practices:

– state loans are no longer granted

– state acts no longer in operational role of the projects

Subsidies to Basic Drainage

•Max 50 % of accepted costs

•Additional 20 % (max), if

- Water protection measures or structural solutions are exeptionally

expensive

- Majority on costs are from silting of flooding due to measures taken

in upper catchment area

• On discretionary environmental procedures subsidy can be 100 %

Separate subsidies for reallocation of land

Field Drainage

Amount of Field Drainage 1900-2010

Field Drainage by Area in Finland

New and Additional Subsurface Drainage

Actors within Drainage 1/2 Farmers

Payer/ Organizer

Funding

Farmers

Ministry of Agriculture and Forestry

ELY-centers (regional Centre for Economic Development,

Transport and the Environment)

Banks

Planning

ProAgria Advisory Centres, ca15 pers.

Maveplan Oy, ca 15 pers.

Privat Planners, ca 15 pers.

Contractors

ca. 80 companies

Actors within Drainage 2/2

Material

Pipes

Jita

KWH

Meltex

Uponor

Plastic equipment

Muotek

Plastweld

AS-Muovi

Gravel- and concreteproducts

Local companies

Training, Research and Developing

Field Drainage Association

Universities

Sedu, Ilmajoki

MTT

Finnish Plastics Industries Federation

SFS

FINCID

RIL - Finnish Association of Civil Engineers

Construction

Ditch depth 1,0 – 1,2 m

Ditch spacing 10 – 20 m

Envelope: gravel 5-10m3/100 m

Pipematerials

Subsidies to Subsurface Drainage

Max 20 % of accepted costs

Interest subsidy max 20 %

Human-Induced Phosphorus and

Nitrogen Load into Waters, Finland

PHOSPHRUS

Agriculture, 69 %

NITROGEN

Agriculture, 57 %

SYKE 2012

Field drainage affects via various means to soil structure and root

depth and therefore into soil carrying capacity.

This affects directly to the farmers income and also nutrient leaching.

Surface and subsurface

runoff vary remarkably

from year to year

Runoff

Principles for

Subsurface Drainage,

Controlled Drainage

and Subsurface Irrigation

Controlled Drainage

Principles for

Subsurface Drainage,

Controlled Drainage

and Subsurface Irrigation

Requirements of controlled drainage

and subirrigation

• Relatively high natural (before drainage) water table in the field need of subsurface drainage

• Topography

- slope < 0.5% (max. 1-2 %)

- uniform field surface

number of control structures (costs), uniform soil moisture,

limitation of horizontal seepage

• Soil

- a good hydraulic conductivity (> 0.5 m d-1)

a good response to control measures - impermeable bottom (< 3 m from the soil surface) limitation of percolation losses

• External water supply for subirrigation

- capacity for plant requirements (ET) and seepage losses

Thank you for your attention!

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