General
National Id
Finland_02
Site name
Nummela, Municipality of Vihti, Uusimaa Region, Southern Finland
Summary
In 2010, the Nummela Gateway Wetland Park (2ha), Finland was constructed both as water environment mitigation landscapes and as urban park. Monitoring of the Nummela Gateway wetland park over a period of three years shows that constructed wetlands rapidly self-establish, resulting in an increase in biodiversity and the establishment of several ecosystem services (e.g. erosion and flood control, and reduction of pollutants in runoff water). The constructed wetland also provides a range of other benefits including opportunities for recreation and education.
Light or indepth?
Light
NUTS Code
Helsinki-Uusimaa
RBD code
FIVHA2
Transboundary
0
NWRM(s) implemented in the case study
Longitude
24.3375
Latitude
60.3277
Site information
Climate zone
cool temperate moist
Mean rainfall
650
Mean rainfall unit
mm/year
Average temperature
4.6
Type
Case Study Info
Monitoring maintenance
Monitoring impacts effects
1
Monitoring location
Catchment outlet
Monitoring parameters
continuous flow and water level , nutrients, conductivity, temperature, pH, oxygen, hydrocarbons, metals, bacteria
Monitoring upstream station
the monitoring is case study specific
Monitoring downstream station
the monitoring is case study specific
Performance
Performance impact estimation method
Edge of Field/Plot
Performance impact estimation information
Monitoring was performed to monitor impacts with regard to water quality and quantity, carbon content in soils, greenhouse gases, vegetation as well as evaluating ecosystem services.
Design & implementations
Application scale
City
Installation date
2010
Age
4
Performance timescale
1 - 4 years
Area (ha)
500
Area subject to Land use change or Management/Practice change (ha)
2
Size
2
Size unit
ha
Peak flow rate
1000
Public consultation
1
Contractural arrangements
1
Design contractual arrangement
| Arrangement type | Responsibility | Role | Comments | Name |
|---|---|---|---|---|
|
Contractual agreement
|
Supporting
|
Implementation
|
for LIFE+ project Urban Oasis
|
Th partnership agreement on implementation of the LIFE+ project
|
Design consultation activity
| Activity stage | Key issues | Name | Comments |
|---|
Design land use change
| Land use change type |
|---|
Design authority
| Authority type | Role | Responsibility | Name | Comments |
|---|---|---|---|---|
Lessons, risks, implications...
Key lessons
1) importance of having monitoring to verify the benefits from the wetland construction;
2) importance of the partnership and engadegment of relevant stakeholders; collaboration between environmental, planning and technical authorities has been crucial
2) importance of the partnership and engadegment of relevant stakeholders; collaboration between environmental, planning and technical authorities has been crucial
Success factor(s)
| Success factor type | Success factor role | Comments |
|---|---|---|
|
Attitude of relevant stakeholders
|
main factor
|
Participatory approaches and engagement of stakeholders in the design and implementation of the process were found beneficial to long-term success. Collaboration between environmental, planning and technical authorities has been crucial. In addition, the local association for water protection (VESY ry) has been an active partner in the project supporting several voluntary actions. The Uusimaa Centre for Economic Development, Transport and the Environment (UUDELY) has participated in project management and monitoring from the |
|
Financing possibilities
|
main factor
|
Initially, the project was funded by municipality and regional development center. LIFE+ project was developed and is implemented 2012-2016 as follow up and expension with similar activities in the area |
|
Conducted assessments (incl. economic)
|
main factor
|
Availability of the information on key ipacts and results from the activities |
|
Other
|
main factor
|
The project combines environmental (water pollution, habitat degradation, etc.) and social aspects (recreation) |
Financing
| Financing type | Comments |
|---|---|
|
Sub-national funds
|
regional authority of the Uusimaa Centre for Economic
Development, Transport and the Environment (UUDELY) |
|
Local funds
|
Budegt of Vihti municipality
|
|
EU-funds: LIFE+
|
For follow up project called Urban Oasis
|
Driver
| Driver type | Driver role | Comments |
|---|---|---|
|
Organisation committed to it
|
To improve the situation, the existing unsustainable means of disposal of runoff water was examined at the watershed level, seeking solutions through a holistic assessment of watershed processes and dynamics. As a result, new wetlands were created along the heavily degraded stream corridor to compensate for land-use changes within the watershed and
to restore lost stream corridor habitats. In addition, a large wetland park named the Nummela Gateway Wetland Park was established at the mouth of the Kilsoi stream. The construction of wetlands was led by the project team and supported by a range of local and regional stakeholders. |
Financing share
| Financing share type | Share | Comments | |
|---|---|---|---|
Policy, general governance and design targets
Policy description
1) due to land-use changes and inadeqaute urban waste water management the Lake Enäjärvi watershed have resulted in poor water quality and related adverse impacts such as increased algal blooms and fish mortality.
2) problems such as erosion, flooding, draught, habitat degradation and low water quality were common in the area, preventing local people from accessing and enjoying from their surrounding natural environment
2) problems such as erosion, flooding, draught, habitat degradation and low water quality were common in the area, preventing local people from accessing and enjoying from their surrounding natural environment
Part of wider plan
1
Policy target
| Target purpose |
|---|
|
Pollutants Removal
|
|
Improved Biodiversity
|
|
Oher Societal Benefits
|
|
Runoff control
|
|
Peak-flow reduction
|
Policy pressure
| Pressure directive | Relevant pressure |
|---|
Policy area
| Policy area type | Policy area focus | Name | Comments |
|---|
Policy impact
| Impact directive | Relevant impact |
|---|
Policy wider plan
| Wider plan type | Wider plan focus | Name | Comments |
|---|---|---|---|
|
Vihti municipality plan
|
Local municipal plan reflects the change in zoning of land use.
|
Policy requirement directive
| Requirement directive | Specification |
|---|
Socio-economic
Costs total
65000
Costs total information
The initial sum was used to restore the river channel and related wetlands, as well to establish
Ecosystem improved biodiversity
1
Information on Ecosystem improved biodiversity
These wetlands were constructed by excavation in abandoned crop fields. Vegetation was allowed to selfestablish. Seven vegetation zones were identified at the Gateway wetland: natural flood meadow by the lake, constructed islands, constructed wetland area, two dryer wet meadow areas, area of Salix shrubs, and adjacent forest edge. Annual monitoring for species and foliar coverage in summers of 2010, 2011 and 2012 (94 area 0.5m2 plots) revealed that the vegetation selfestablishment at the Gateway wetland was rapid, rich in taxa, and dominated by native wetland species. Only two alien species were identified: Elodea canadensis in deep water areas and Epilobium adenocaulon in dryer meadow areas. Coverage exceeded 90% in 2012.
Ecosystem impact climate regulation
Impact on GHGs (net emissions and storage) including soil carbon
Information on Ecosystem impact climate regulation
GHGs have been continuously monitored at the Gateway wetland by the eddy covariance method from air (measures fluxes) and directly from water (measures concentrations).
Measurements of GHG concentration in water during winter 2012-2013 indicate that the site has been a source of CO2 and CH4 into the atmosphere. However, ice cover has prevented 4
GHG emissions. The GHG concentrations in the water were sensitive to changes in flow rates. Polluted spills within the urbanized areas impacted water quality as well as GHGs released from the water at the wetland.
Measurements of GHG concentration in water during winter 2012-2013 indicate that the site has been a source of CO2 and CH4 into the atmosphere. However, ice cover has prevented 4
GHG emissions. The GHG concentrations in the water were sensitive to changes in flow rates. Polluted spills within the urbanized areas impacted water quality as well as GHGs released from the water at the wetland.
Biophysical impacts
Peak flow rate reduction
40
Peak flow rate reduction unit
%
Ecosystem erosion control
1
Water quality overall improvements
Positive impact-WQ improvement
Information on Water quality overall improvements
Wetland decrease the risk of eutrofication in Lake Enäjärvi.
Water quality Improvements Phosphorus (P)
9
Water quality Improvements (P) unit
% reduction pf pollutant
Information on Water quality Improvements (P)
Wetland retained phosphorus comparatively most efficiently in July, but terms of terms of absolute quantity in October – November.
Water quality Improvements Total Suspended Solid (TSS)
12
Water quality Improvements (TSS) unit
% reduction pf pollutant
Water quality Improvements (TSS)
Monitoring data from late April 2012 show two peaks of suspended sediments following two rain events. In both cases the wetland reduced sediment load into the lake (by 24% and 12%, respectively)