The water quality of the lakes in the Imatra region

Information on the ecological status of most lakes can be found on the color map below. The map is updated every six years at the Southeast Finland ELY center as part of water management.

Color map: The ecological state of the lakes in the Vuoksi water management area
Karelia's Pyhäjärvi

• The ecological status is excellent: color code blue

Karelia's Pyhäjärvi is a barren and clear-water large lake stretching from Parikkala's Uukuniemi to North Karelia and to the Russian side, which is both a provincially and nationally valuable Natura 2000 site. Pyhäjärvi flows into Orivete in the north, which is part of the Saimaa watershed. Several ancient monuments have been found in the fine landscape areas of Uukuniemi's Papinniemi. Pyhäjärvi has been lowered by a total of 1,5 meters in the 1800th century.

The main scattered polluters of Pyhäjärvi are forestry and agriculture, scattered and holiday settlements. North Karelia's ELY center is the authority responsible for Pyhäjärvi's water management. The Karjalan Pyhäjärvi ry promotes the protection of the lake, and the Uukuniemi leisure residents' ry, or Vasukkaat, also works for the sake of the lake. A foundation is planned for the area of ​​Pyhäjärvi, Puruvesi and eastern Pihlajavesi in 2024 to promote water management.

Lake Pyhäjärvi 2023 water management and Natura 2000 area management and use plan 2023

Pyhäjärvi Association of Karelia

Photo: Karjalan Pyhäjärvi, Paakalahti, Uukuniemi.

Little Rautjärvi

• Ecological space must be avoided: color code orange

Pieni Rautjärvi or Pien-Rautjärvi located in Parikkala is an important bird lake; especially the Pohjanranta and its surroundings is a migratory rest area for birds. The lake is narrow and shallow; its water level has been lowered several times in the 1800th century and the beginning of the 1900th century in order to make fertile bank fields available. With the subsidence, the lake narrowed into three water basins, which are heavily burdened by agriculture. A management and use plan has been drawn up for the lake's Natura 2000 natural sites. The lake has a couple of birdwatching towers and also has fishing and recreational value. 

As a renovation project, the Fish for Benefit project of the Imatra region's environmental initiative was implemented in the years 2018–2020, where mowing and management fishing were carried out in cooperation with Saare cooperatives. At the same time, agricultural water protection plans were drawn up, which were implemented in the follow-up project of the Pien-Rautjärvi lake lowering company and cooperatives in the years 2021–2023: basins that benefit both birdlife and water quality were dug near the shore. The national Helmi living environment program also participated in the work. The water quality of the lake has visually been significantly better than before and only small amounts of algal blooms have been observed. The work for the lake will continue in 2024.

Photo: Pien-Rautjärvi, management fishing in the Fish for Benefit project in 2018

Simple brain

• The ecological status of the eastern part is good: color code green
• The ecological status of Sokkiiselä, Lemmikonselä and Kirkkoselä is satisfactory: color code yellow
• The ecology of the southern part of the lake, i.e. Kurhonselä, is good: color code green

Over the years, the water level of Simpeleirve has been lowered by almost 6 meters. This is how once fertile coastal fields were obtained to make living conditions easier. On the other hand, agriculture later also became a burden on Simpeleirve. Other burdens include forestry, scattered settlements and Parikkala municipal wastewater treatment plant, which was originally built for the needs of a large dairy. Now the Särkisalmi treatment plant uses membrane technology and its emissions are lower. Simpeleiervi used to be a good whitefish lake, but nowadays you can catch pike in the lake. The change in the fish population indicates the development of the lake in a more lush direction. Siikalahti has turned into a bird bay, a Natura 2000 site, due to the lowering of the lake's water level.

The condition of the simple vein has deteriorated in the 2000st century. Efforts have been made to rehabilitate the lake with projects, and the Simple Lake project led by the municipality of Parikkala is currently underway, in which suitable wetland sites for the catchment area are being searched, as well as management fishing and mowing.

The Lahdenpohja, which has receded from Lake Simpelejärvi due to the subsidence of the lake, is in an ecological state that cannot be avoided. In order to restore it, the Saimaa Water Protection Association is running the LAKU project starting in 2021. The project also rehabilitates the nearby Akonpohjan Bay, the Suuri Rautjärvi catchment. The LAKU continuation project is planned for 2024.

Simpleilarve renovation project 2022–2024

Saimaa's Water Protection Association/Simpeliervi

Saimaa water protection association/LAKU project

Photo: Kurhonselkä of Simpeleilarven facing Joukionsalmi in 2009.

torso

• The ecological status is excellent: color code green

Erämainen Torsa is located on the border of Rautjärvi and Ruokolahti in Pohja-Lankila, extending southeast to Pallaitniemi. Although its northern end is subject to a slight load from peat production, it has been titled as one of the best lakes in Southeast Finland. The lake's tributary Torsanjoki-Silamusjoki has been renovated to revive the trout population. It is also hoped that tile salmon will rise from Hiitolanjoki all the way to Torsa.  

Photo: Torsa beach pier in summer 2013.

Nurmijärvi

• The ecological status is excellent: color code blue

Nurmijärvi is a clear-water and barren lake that is sensitive to changes in the catchment area. The Nurmijärvi Protection Association was founded in 2017 and has done determined work for the sake of the lake. The Nurmijärvi - Rautjärvi pearl project, year 2018–2020, received the Kärki-Leader ry award as the best project in 2023.

The conservation association built hay bale filters in the main canals leading into the lake. In 2022, a pipe dam and settling basin were built in the ditch that descends to Vertanenlahti. In order for the lake to remain in excellent condition, special attention must be paid to diffuse pollution, especially to the protection of water from forestry measures. Information about the current state of the lake has been compiled on the website of the Nurmijärvi conservation association.

Nurmijärvensuojelu.fi

Picture: Nurmijärvi has a lot of big boulders in the shallow Vertanenlahti: Kirkkivi and Höllökivet.

Lake Purnujärvi

• Ecological space must be avoided: color code orange

Purnujärvi is shallow and eutrophic from agriculture. The Helisevänjoki river runs through Länsipää, which carries silt with it and occasionally causes water quality to deteriorate. The lake has had a management fishing and water protection education project in 2020–2021.

Photo: Familiarization trip to Purnujärvi in ​​2018.

The crunch

• The ecological status is excellent: color code blue

Kärinki-järvi is a clear-water and barren lake, about 25 meters deep, in the vicinity of Ruokolahti's central harbor. The neighboring Pieni Kärinki, whose ecological status is good, flows into Kärinki, bringing additional water there. The waters from Käring continue to flow to Haapavede in Pappalanlahti along Myllyjoki via Myllylammi. There is a regulation dam built for the old mill in the river.

Photo: The clear-water Myllyjoki flows from Käring into Pappilanlahti, 2015.

Haapavesi-Kauvonselkä

• The ecological status is good: color code green

The water area in front of Saimaa's Ruokolahti is called Haapavesi. It continues westward as Ihalansalmi and further as Kurenvirta to Raaniemensela and Kauvonselä, from where there is a connection to Suur-Saimaa via Vuosalmi. In the middle of the water area in front of Ruokolahti is the large Äitsaari, "mother island", where there are also several lakes. East of Äitsaari is Härskiänsaari, and a causeway was built between the islands in the early 1990s.

In Soinilansalmi, after the construction of the causeway, siltation of the bottom and an increase in aquatic vegetation were observed. The bridge opening of the embankments was therefore enlarged in 2018. Haapavesi-Kauvonselkä is eutrophic: it is burdened by both agriculture and forestry. In addition, there are many scattered settlements in the water area, whose waste water can eutrophicate the water area. The Sininen Haapavesi water protection project was implemented in 2012–2014. It promoted water conservation in forestry and agriculture, and rehabilitated waterways with mowing and management fishing.

Saimaa water protection association/ Water quality reports of Soinilansalmi and Ruokolahti's surrounding Äitsaari

Photo: Tetriniemi fishing competition 2014 in the Sininen Haapavesi project.

Lake Immalanjärvi

• The ecological status is excellent: color code blue

Over the years, Immalanjärvi in ​​Imatra has received a lot of attention, not a swamp. It is a pearl of pure water in Salpauselkä's armpit. Surveys, research and water protection measures have been carried out. Next to the northern part of the lake is Vesioronkanka's extensive 1st-class groundwater area, which secures the lake's supply of clean water. However, forestry and agriculture also burden Lake Immalanjärvi, especially on the Laitilanlahti side.

The Saimaa water protection association has implemented a cooperation project in Immalanjärvi in ​​the years 2021–2023. 
In the project, water management planning and implementation of the forest and agricultural area at the catchment area level was carried out with the aim of reducing the load on Laitila Bay without forgetting the aspects of climate change.

Saimaa water protection association/Immalanjärvi project

Saimaa water protection association/ Immalanjärvi water quality reports

Photo: Hiekkoinlahti, Immalanjärvi 2015.

Vuoksi and South Saimaa

• The ecological state of South Saimaa is partly good and partly excellent: color code green and blue
• Vuok's condition is good: color code green

The southernmost part of Saimaa, Lower Saimaa, is observed in the so-called as a joint monitoring, which means that the large industrial plants discharging waste water into the Saimaa River are obliged in their environmental permits to monitor the environmental effects in the water body. The biggest changes in South Saimaa's water quality took place in the early 1990s, when the biological wastewater treatment plants of wood processing plants were put into use. According to the water quality index developed by the Saimaa Water Protection Association, Saimaa's water quality from Tiruniemi to Vatavalkamma remained constant until the early 2000s, after which it has slowly deteriorated. In recent years, the deterioration of the water quality in the area is indicated by the increase in chlorophyll concentrations, i.e. its level of luxuriance has slightly increased. 

Note The Saimaa water protection association's water quality index is different from the ecological classification of water bodies. The attached maps of the Water Protection Association's reports describe water quality using these indices.

Lower Saimaa collects water as far as Iisalme, the water flows down to Vuoki and further to Laatokka. The stream has been heavily transformed into a water bed. In the action program for the water management of Southeast Finland for the years 2022–2027, it is mentioned that the goal is to implement all the technical and economic measures that can be used to get a naturally increasing population of migratory fish in Vuosi. Imatran Kaupunkipuro was built in Imatrankoski in 2014 to promote the reproduction of trout.

According to the water quality classification developed by the Saimaa Water Protection Association, Vuoksi's water quality has been between good and satisfactory in the 2000st century. In the 2020s, the water quality seems to have slightly improved.

Saimaa water protection association/ South Saimaa water quality reports

Saimaa water protection association/ Vuoksi water quality reports

Photo: Vuoksi fogs up in the bitterly cold winter of 2016.