Water retention management in the broader area of Ancient Olympia, Elia, Greece

National Id
Greece_01
Site name
Alpheos Water Body (GR0129R000215044H )
Summary
The project refers to water retention management in the broader area of Ancient Olympia, Elia, Peloponnese, Greece; that is afforestation of mountain areas. The measures include the temporary installation of structures utilizing locally available timber in order to increase water retention as well as targeted planting of forests in mountain areas that can help stabilize hill slopes, thereby reduce erosion and potentially leading to greater water retention in the mountain areas. The primary measures targets include flood control and flood risk mitigation and the secondary biodiversity conservation. The main success factors was the positive attitude of decision makers, the willing of stakeholders and the positive public perception and the existing expert knowledge and tools.
The in-depth description of the case study
NUTS Code
Δυτική Ελλάδα (Dytiki Ellada)
RBD code
GR01
Transboundary
0
Data provider
Maggie Kossida, IACO
NWRM(s) implemented in the case study
Longitude
21.378061
Latitude
37.3835085
Climate zone
warm temperate dry
Mean rainfall
863,049987792969
Mean rainfall unit
mm/year
Average temperature
16,7000007629395
Mean runoff
675
Mean runoff unit
450 - 600 mm
Type
Case Study Info
Light or indepth?
In-depth
Monitoring impacts effects
1
Monitoring location
Edge of Field/Plot
Performance impact estimation method
Unknown
Performance impact estimation information
Non applicable
Application scale
Other
Installation date
2007-11
Lifespan
5
Age
7
Performance timescale
1 - 4 years
Area (ha)
49,5
Area subject to Land use change or Management/Practice change (ha)
49,5
Design capacity description
The temporary structures utilizing locally available timber have been designed to reduce the hill slopes thus attenuate the surface runoff as well as the sentiment volume. This measure enables the increase of soil moisture, water absorption, and infiltration. Additionally, it creates suitable sites for natural regeneration or technical afforestation of the burned area.
The maximum volume of runoff water that can be retained has not been assessed as this was not originally a water retention application but the restoration of the surrounding of the archeological site.
Constraints
The factors that influence the selection and design of the NWRM is morphology, vegetation, climate and geology of the area. The morphology of the area (large slopes), increases surface runoff, leading to soil erosion and increased risk of landslides as well as increased flood events. To address this, the use of geotextile had to be implemented in most sloping and vulnerable positions. The vegetation (after the fires) has eliminated and a hydrophobic layer in the soil has been created by the combustion of organic matterwhich increases surface runoff and flood risk. The local climate, with an annual precipitation of over 1.000 mm and often intense events, also tends to increase the intensity of flood events.
The soils of the study area are also very loose and corrodible; thus vulnerable to the rainfall.
A high challenge for the temporary small structures is the hydraulic undercut.
Improving the condition of existing rainwater drainage system e.g. cleaning of the rainwater drainage system to avoid filling the road network with logging waste and increasing the flood risk.
Favourable preconditions
The necessary preconditions are the climate conditions and the soil properties and characteristics.
Design contractual arrangement
Arrangement type Responsibility Role Comments Name
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
Other
Determination of design details of the measure
Institute of Mediterranean and Forest Ecosystems
The Institute along with NAGREF are the scientific / technical responsible parties
Other
Monitoring
Hellenic Ministry of Culture and Sports . The main stakeholders involved for the study and the implementation of the restoration of the site were the
The Ministry is the beneficiary, responsible for initiating and monitoring the interventions procedures
Other
Monitoring
Z†™ Ephorate of Prehistoric and Classical Antiquities
The Ephorate is the regional cultural authority of the pilot area
Other
Determination of design details of the measure
Forest Products Technology of the National Agricultural Research Foundation (NAGREF)
NAGREF along with the Institute of Mediterranean and Forest Ecosystems are the scientific / technical responsible parties
Key lessons
The retention measures are based on the principals of changing the area morphology as well as the soil composition. Thus, the length of the slopes was shortened, the surface roughness and the soil infiltration rates were increased, the surface runoff and sentiments were delayed and the soil humitity was increased. Water retention management can be implemented through improvement of the soil and changes in the landscape morphology.
Success factor(s)
Success factor type Success factor role Comments
Attitude of relevant stakeholders
main factor

The active involvement of the two Institutes was of critical importance

Attitude of decision makers
secondary factor
Existing staff and consultant knowledge
secondary factor

The expertise and knowledge tools of the two Institutes was important

Financing
Financing type Comments
Private funds
Donations
EU-funds: Rural development funds
Agricultural Development Programme
Barrier
Barrier type Barrier role Comments
Other
main barrier
The main implementation barriers were physical constraints such as the high slopes.
Driver
Driver type Driver role Comments
Other
main driver
Morphology, vegetation, climate and geology of the area.
Financing share
Financing share type Share Comments
Policy description
The specific interventions aim at tackling the environmental impacts of the significant wildfires of the study area in 2007. The principal aim of the works includes reduction of soil erosion and flood management. The interventions also include burned trees harvesting and restoration actions on the existing vegetation and on the tree crops.
Part of wider plan
0
Policy target
Target purpose
Runoff control
Peak-flow reduction
Erosion Control
Improved Biodiversity
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
Policy requirement directive
Requirement directive Specification
Direct benefits information
The direct benefits include the reduction of the flood risk, the mitigation of soil erosion, the improvement of the micro-environment as well as the aesthetic restoration of the affected area.
Ancillary benefits information
Ancillary benefits include the increase of infiltration / percolation and recharge of aquifers; this water can be used for different purposes (e.g agriculture) as well as for ecosystem services. Also the aesthetic improvement of the area has positive societal impacts
Costs investment
2762500
Costs investment information
This amount includes the fixed capital cost, infrastructure, construction and landscape rehabilitation.
Costs capital
1262500
Costs land acquisition
1500000
Costs land acquisition unit
€ (total value)
Costs operation maintenance
The operational cost for irrigation as well as for pruning and fertilizer application was not assessed.
Costs total information
No information available
Ecosystem improved biodiversity
1
Information on Ecosystem improved biodiversity
The wildfires had significant impact on the area biodiversity and the restoration measures included using species from the surrounding locations in order to restore the decreased biodiversity
Information on Ecosystem provisioning services
Not relevant for this application
Ecosystem impact climate regulation
No information available
Information on Ecosystem impact climate regulation
The micro-climate and micro-environment was positively affected by the implemented measures; however the degree of impact was not assessed
Information on retained water
The volume of retained water was increased due to the temporary log structures as well as the improvement in the area vegitation after the afforestation
Information on increased water storage
The measures increased the retaining of water for longer period enabling the infiltration/percolation and recharge of aquifers.
Information on runoff reduction
The measures improved the runoff control as the velocity of water volume was reduced leading to decreasing the intensity and frequency of floods.
Water quality overall improvements
Not relevant for this application
Information on Water quality overall improvements
Not relevant for this application
Soil quality overall soil improvements
Positive impact-SQ improvement
Information on Soil quality overall soil improvements
The measures have a direct impact on the overall soil quality as afforestation of the area succeeds in eliminating the hydrophobic layer that was created in the soil after the fires and thus increase soil storage capacity. The fires have created the porosity of the soil to decrease, thus the restoration has positive impact on the soil infiltration capacity. Also the soil is improved due to the increase of the moisture.

Partners

Logos of all partners of NWRM project