The area around Malom Lake, one of Oroszlány’s proudest landmarks, is being revitalised

In Oroszlány, the green space development covering a third of the approximately 10-hectare area around Malom Lake is being revitalised in line with the ‘sponge city’ concept. The aim is to retain water, preserve biodiversity, reduce the heat island effect and expand areas for active recreation. Rainwater is managed in a comprehensive manner across the site – for example, through the creation of rain gardens and permeable paving – during both periods of heavy rainfall and drought.

Climate change is highlighting the importance of the urban lake

The current form of the man-made Malom Lake was established in the early 1970s. The earth excavated during the digging of the lake bed was used to construct embankments, dykes and the sub-base for nearby housing estates.

The town lake plays a multifaceted role in the life of Oroszlány:

It is a key element of the region’s water management, managing rainwater and minor flash floods from the Vértes Mountains. The water bodies within the town and the surrounding areas, which play an important role in the community’s daily life, will also have an increasingly significant role to play in mitigating the effects of climate change.

 

Emergency alert

In recent years, prolonged periods without rainfall have caused a number of problems at Oroszlány’s largest inland lake.

In the summer of 2021 and in almost every year since, the Kertekalja and Svandabereg streams that feed the lake have dried up for varying lengths of time due to drought; the Labanc stream was the sole source of water, but even its flow was not always sufficient. As the water warmed due to high average temperatures, algal blooms began to form, and the lake’s wildlife faced challenges due to periodic oxygen depletion.

The emergency was resolved when jet-skiers sped across the lake and firefighters used water cannons and then submersible pumps to circulate the water, thereby preventing a mass fish kill. It became imperative to address the situation comprehensively and find a solution for retaining rainwater.  

The transformation affects almost the entire area surrounding the lake

The comprehensive renovation of the area around Malom Lake is being carried out by the experts at STRABAG specialists are carrying out the comprehensive renovation of the area surrounding Malom Lake based on plans by Partner Mérnöki Iroda and Gaia Kertműhely. The investment goes beyond simple landscaping.
The project affects almost the entire immediate surroundings of the lake, across several interconnected sites – Dániel Hajnik told our portal. The site manager of STRABAG added that the area affected by the works was partially developed, but the condition of the footpaths had deteriorated, they had become incomplete, and the surfacing had worn out. The aim of the project is to create a well-organised, usable, sustainable and safe community space that is also close to nature.

The project is being carried out in stages, which include:

• – the construction of the promenade in three phases,
• – the asphalting works,
• – the design of the playground and its surroundings,
• as well as the landscaping of the lake area and the planting of vegetation.

A new walkway is being built with new paving to ensure the lake can be walked around in its entirety

The most striking aspect of the construction work is the creation of a 1.4-kilometre-long network of footpaths that allows visitors to walk around the lake. The surface, consisting mainly of crushed stone, allows rainwater to seep into the ground, whilst sections subject to heavier use will be paved with paving stones, sloping down towards the lake’s water surface. Street furniture will be installed along the promenade.
The accuracy of the works is monitored through continuous levelling. This optimises the height relationships between the paving and the ground levels. The latter is a task of paramount importance not only for safe traffic flow and the durability of the surfaces, but also for drainage.
A public lighting system is being installed around the lake: on the northern side with solar-powered „smart” lights, and on the southern side with a mains-powered solution.

Thousands of cubic metres of soil are being moved at the site

A viewing hill will be directly connected to the promenade. From the hilltop, visitors will be able to scan the surrounding area through binoculars. Dániel Hajnik explained that during the earthworks and landscaping, 2–3 thousand cubic metres of soil will be excavated, which will then be used to rebuild the site. No clean humus topsoil will be extracted; the humus-rich sandy soil mixed with gravel, stones and crushed stone will be used on the viewing hill and behind the Kayak House.

This is also important from a contractor’s perspective because on-site reconstruction reduces unnecessary material movement, whilst the landscaping can be better tailored to the project’s requirements. The levelling and landscaping are carried out under geodetic surveying and continuous monitoring, and long-term stability is ensured through proper compaction.

The site manager emphasised that the greatest geotechnical challenge lies in the construction of the viewing hill. During the construction of the layered embankment, attention must be paid to ensuring the correct moisture content, avoiding overfilling, and allowing sufficient time for consolidation. The slopes of the hill, formed from hundreds of cubic metres of fill material, are being stabilised with grass planting, whilst one side is being reinforced with dry-laid limestone blocks. The construction must ensure both structural integrity and a natural appearance that blends into the landscape.

Bagolyvár invites children to come outdoors

In addition to the new play equipment, which has been named Bagolyvár, a fitness trail and a table tennis table will also be installed. The road leading to the Kayak House and the car park next to the hill with the viewing point will be resurfaced with asphalt.
The focus on climate action is also reflected in the development of transport and community infrastructure.

The car park in the area between the apartment blocks and the lake is being expanded,. and the surface will be laid with grass pavers, thereby helping rainwater to drain away on site.

The layer structure consists of a 30-centimetre-thick repair layer of sandy gravel, a 20-centimetre-thick layer of M63 mechanical stabilisation, a 3-centimetre-thick bedding layer and the turf grid.

The area is being redesigned with a rain garden and a water retention approach

One of the project’s key climate adaptation measures will involve the creation of a rain garden and other shrubbery strips to provide ground cover, the removal of sections of kerb, and the gradual dispersal of rainwater across green spaces. The earthworks associated with this project phase have already been completed. Following the creation of the washed gravel strip, the tasks remaining to be completed include preparing the growing medium and planting the vegetation.
In the vicinity of Malom Lake, the retention and utilisation of rainwater and water from the surrounding streams is particularly important, as the lake’s catchment area is approximately 43–44 square kilometres, and whilst the annual rainfall is around 600 millimetres on a long-term average, its distribution is becoming increasingly extreme.

Elements of lake engineering designed to improve water quality are also being produced

As part of the project, a new floating jetty and a submerged aeration system will also be installed. The installation of the two aeration fountains will help to circulate the water, enrich it with oxygen and humidify the air.

The project will also involve a significant amount of planting work at the end: the programme includes laying turf, planting trees, ornamental grasses, shrubs and perennials. This work will only be carried out after the paving has been completed, to ensure that the heavy machinery used does not damage the newly planted vegetation. Following planting, the contractor will provide continuous watering until the plants have taken root, and stakes will be used to help the trees develop straight trunks.

They are proceeding with sector-specific coordination and a schedule adapted to the weather

According to information provided by STRABAG, the coordination of the wide-ranging specialist works is ensured through schedules, several on-site and written consultations each week, and ongoing coordination. However, the construction work is also significantly influenced by the waterside environment and the weather, particularly periods of rainfall, which may alter the schedule for earthworks and paving.
The regeneration of Malom Lake in Oroszlány is a complex project from the perspectives of urban development, climate change adaptation and construction.

The project not only revitalises a lakeside area that has fallen into disrepair, but also incorporates technical and landscape architectural solutions into the urban space that promote water retention, a greener environment, energy-efficient operation and long-term usability.

The project entitled ‘Green Development in Oroszlány’, reference number TOP-PLUSZ-1.2.1-21-KO1-2022-00046, is being implemented under the Széchenyi Plan Plus programme with funding of 300 million forints at an intensity of 100% (%).