the limuthi
river
This project is a landscape architectural elaboration of the development strategy for Tirana and surroundings, made by a multidisciplinary team of students from Delft University of Technology and several polytecnic universities in Albania. Technical and ecological interventions and a strategic cooperation proposal between residents, municipality and development organizations come together in a design in order to tackle problems in the Limuthi river valley, such as flooding, waste disposal and aesthetic degradation.
Project type · Multidisciplinary project
and landscape architecture design
Date · 2018
Location · Tirana, Albania
Mentors · Dr. Fransje Hooimeijer
Keywords · Ecological Restoration, Coastal Management, Mangrove Reforestation, Landscape Architecture, Spatial Design, Flood Protection, Urban Ecology, Design Research, Research by Design
In collaboration with:
Albania is largely surrounded by mountains, from where many rivers originate and flow to the coast. Most of these rivers are artificially guided through the wide valleys towards the Adriatic Sea. Countless lakes and valleys have been dammed to retain water and to generate hydropower. In the dry season, the cities and agricultural areas benefit from this extensive water network. However, in the rain season, this intensive use of the water network causes bottlenecks, such as in the outskirts of the capital city of Tirana at the bottom of the Limuthi valley. In the past, many floods have already caused great damage both in the valley and further downstream where important industry, agriculture and infrastructure are located.
The Limuthi river flows gently through farmland and small villages and informal settlements. This agricultural landscape is both drained and supplied by water from the river which is sourced by three basins up in the hills. In winter, the river can contain up to 30 times more water water than its average discharge and floods vast parts of the valley. This has a huge impact on the farmers, which have to they restore the damage to their homes and fields every season. As well it causes significant economical damage to the light industrial area City Park further downstream. On top of this all, the safety of the residents is at risk when this gentle stream changes into a wild river.
The challenge in the Limuthi valley is to control the river, both in rainy and dry season. The narrowed river bed, which is mainly caused by cultivating land for agriculture, needs to be widened and protected against erosion. This is the only way to guarantee a safe living environment and allow agriculture. Also, a social environmental problem occurs: trash bags, construction materials causing major blockades in the river, which increases natural sedimentation and result in a obstruction of the water flow. Besides not having a garbage system, the local residents also lacking awareness. People do not know why floods reoccur every year and what they can do to prevent this. These two major challenges are interrelated and need to be approached at the same time, because a technical design for the river could only work with support of the local community.
The vision of the project is to tackle the challenges in the Limuthi valley, through a collaboration between all stakeholders for implementing technical and landscape architectonic interventions, explained below as solutions and tools. To further elaborate on various types of issues mentioned in the previous chapter, the interventions are divided into three categories:
Blue is water related, such as the water system. riverbanks and water control elements.
Green is environmental, including the ecosystem, soil and planting of the riverbanks
Red is the social system, focussing on awareness and creating a rewarding system.
The title Limuthi Re-cycle valley is based on reintroducing the bike as a means of transport in the valley, by designing the supporting infrastructure, to use for the residents as a way to collect and transfer waste.
Commercial zone SH2
Right at the bottleneck of the river is the location of highway SH2 and a commercial zone parallel to is. Both have high economic value to the region and the whole country. SH2 is the only connection between port city Durres, the capital and the airport, so therefore essential for import, export and tourism. The commercial zone called City Park provides the bigger area with light industry, shops and leisure. Floods occurring at this bottleneck can have unforeseeable consequences for the economy.
Agriculture
The Limuthi valley is characterized by arable farming in the centre, between two branches of the river. Clay sediments deposited by the river make this soil fertile and suitable for the cultivation of annual crops such as tomatoes and zucchini. Various fields have been converted into plastic greenhouses to increase efficiency, this is also a form of unregistered building.
The area is supplied with water by an artificial water structure of ditches in the shape of a fishbone. Because of the slope in the landscape, the diagonal structure ensures the distribution of water and its drainage for the cultivation of crops. In case of a flood, this fishbone structure can actually cause more flooding in the middle of the valley, considering its dimensions.
Water system
Water is retained and discharged into a system with three zones, which are controlled by locks and thresholds. Zone 1 is between the reservoirs and the agricultural area, zone 2 is the agricultural area and zone 3 is where all the tributaries together form the Limuthi river, just before the bottleneck at SH2. The agricultural land in zone 2, between the two rivers, can function as a floodplain. Here, water can be retained on the land in case of an extreme flood.
River section
The sections on the right show a new shape of the river bed. On the bottom, at level 1, there is a concrete frame that guides the river downstream and prevents erosion. A biodegradable cloth lies on the slopes between the second and third
level, that functions as a foundation for the planting. The slopes are asymmetrical designed to create different water depths, that support different plants and other water creatures. Which side is higher or lower depends on the direction and curves in the river. In dry seasons, the higher side is accessible via stairs that appear every now and then. There is a cycling and walking zone on both sides of the river, that is separated from the road with a line of trees.
Planting
Plants in the riverbank between the second and third level hold sediments, decrease the velocity of the water and filter it. Besides that they create an environment
for different fish species, insects and birds. The two different water levels can be defined as “marsh” and “wet” and have different planting schemes. Below, possible plants are shown for each habitat. The trees on the sides of the river, at level 3, should be resistant to possible flooding, like willow and poplar.
Winter
During the rainy season in winter the stepped river
bank can be filled up to the third level. Because of the zoning plan and the water control elements, it is possible to maintain different water levels in the zones. The agricultural can be flooded and water can be retained in case of an extreme high water level. The fields are not in use and will turn into wetland and attract wading birds.
Summer
In summer the water level drops to the second level
of the stepped river bank or even below. Thresholds in the water systems prevent the river from drying out during this season, so that the fields can still be supplied with water and life in the river will die from drought. Plants on the first level of the slopes hold sediments to prevent erosion and collapse of the sides. Housing areas, cattle and crops only can be found on third level of the river bank, to ensure them to be out of the reach of the water.
River section
The sections on the right show a new shape of the river bed. On the bottom, at level 1, there is a concrete frame that guides the river downstream and prevents erosion. A biodegradable cloth lies on the slopes between the second and third
level, that functions as a foundation for the planting. The slopes are asymmetrical designed to create different water depths, that support different plants and other water creatures. Which side is higher or lower depends on the direction and curves in the river. In dry seasons, the higher side is accessible via stairs that appear every now and then. There is a cycling and walking zone on both sides of the river, that is separated from the road with a line of trees.
Planting
Plants in the riverbank between the second and third level hold sediments, decrease the velocity of the water and filter it. Besides that they create an environment
for different fish species, insects and birds. The two different water levels can be defined as “marsh” and “wet” and have different planting schemes. Below, possible plants are shown for each habitat. The trees on the sides of the river, at level 3, should be resistant to possible flooding, like willow and poplar.
Rewards
In order to create support for the interventions in the Limuthi valley, a strategic collaboration (page 11) was devised, involving residents, municipality and Ecovolis community. In this elaboration it is specifically about creating support and raising awareness among the local residents. The combination of reintroducing the bicycle as a sustainable means of transport and collecting waste locally is the objective. The citizen is rewarded with bicycles and repairs for correctly collecting waste, separating it and bringing it to an assembly point.
Benefits
The advantages of this system are that the local residents become more aware of their waste. By attaching a reward to their actions, waste gets a value and will no longer end up as pollution in the rivers. The overall benefits for all stakeholders (municipality or Tirana, Ecovolis and residents) is to create a clean and attractive area that has potential for recreation and tourism given its location.
Common objective
Besides creating a clean and attractive area, waste collection also contributes to the safety of the inhabitants of the valley and the commercial area along the SH2. Accumulated garbage in the river can no longer cause flooding. This will contribute positively to the entire water management plan proposed in this report.
