But there is growing disquiet in this rural idyll with more and more summer houses up for sale and farmers battling arid land and crop losses amid escalating protests about the impact of lignite coal mining in the area.

Residents ranging from fishermen and farmers to mayors and small business owners say water in the region's lake system is disappearing, drying out farmland and jeopardizing the region's economic base in agriculture and, more recently, tourism.

Drought and climate change, however, are feared to not be the only culprits, with mining of lignite, or brown coal, sapping underground waters and pitting residents against major energy company ZE PAK's proposal for another new mine.

Grzegorz Skowroński, the mayor of Wilczyn, a municipality about 200 km (125 miles) west of Warsaw, said Lake Wilczyńskie's water level has fallen five metres (16.4 ft) since 2011 and is dropping up to four centimeters a week now.

"The state of the lake today is catastrophic and nearby lakes are affected too as they are all inter-connected," Skowroński told the Thomson Reuters Foundation.

WETLANDS DISAPPEARING, CANALS DRYING UP

Wilczyńskie and four other nearby lakes are part of Pojezierze Gnieźnieńskie, a nature reserve protected under the European Union's Natura 2000 network designed to offer a haven to valuable and threatened species such as the area's oak trees.

Historically one of the driest regions in Poland, rainfall has been particularly low in recent years and the fall in Lake Wilczyńskie waters and other nearby lakes is clearly visible.

A pier in Lake Ostrowskie now sits almost entirely on dry land while canals previously linking adjoining lakes contain no water. Wetland plants sit in dried clumps away from the water.

"The lignite mines are definitely to blame. The lake dropped by five metres since they started to massively drain the soil to dig for coal at the Jóźwin mine," Skowroński said.

Jóźwin is one of three open-pit lignite mines in the region operated by KWB Konin, an arm of ZE PAK (Zespół Elektrowni Pątnów-Adamów-Konin SA), the second largest lignite electricity producer in Poland which was formerly state controlled.

ZE PAK, controlled by billionaire Zygmut Solorz-Zak since 2012, operates four power plants in Wielkopolska which are fueled by lignite, the second most important source of energy in Poland after hard coal, and argues a new mine is needed to supply fuel for these plants.

Despite pressure on the coal industry to abide by the European Union's energy and climate policies, the Polish Treasury confirmed it is studying an offer from Solorz-Zak to return the Warsaw-listed power group to state-control.

WATER DROPS NOT US: COMPANY

KWB Konin said the water drops are not the company's fault while acknowledging that the mines siphon groundwater from surrounding land before excavation can start in the open pits.

Grzegorz Frąckowiak, KWB Konin director of investments, said regional authorities are preparing to finance a plan to replenish waters to Lake Wilczynskie, proving the company is not responsible or it would have to pay for this.

"Open pits have existed and continue to exist in this region and look how many lakes there are," Frąckowiak told the Thomson Reuters Foundation.

Pointing to a map showing the company's other mines, he said the company had worked the region for 70 years and "those lakes continue to be here".

"There is no question that in our activity we drain water and then throw it out .. but if you sit on the edge of any of our mines and look around, you see green lands and farming taking place right next to the pit."

Requests for an interview with ZE PAK did not receive a reply.

WE NEED THE WATER BACK: COMMUNITIES

Experts say the removal of groundwater for mining creates a so-called 'cone of depression' and the biggest water level drops occur in areas closest to the mines.

"We have to dig wells 100 metres deep now if we want to have drinking water," says Ewaryst Matczak, the mayor of Strzelno, another locality in the vicinity of the Jóźwin mine.

"The problem is that after mining, it is cheaper for the company to just dump the water into the river Warta from where it goes into the Baltic Sea instead of cleaning it up and pouring it [back] into our lakes," said Matczak.

"We need them to keep the water here."

Poznan University Amad Michkiewicz biologist, Julian Chmiel, said the location and structure of the region's lakes and wetlands showed they are connected to groundwater aquifers affected by the mines' underground drainage.

"[There is] no doubt such strong and directional lowering of levels of groundwater aquifers and superficial waters is caused by mining activities," he said, adding many native plants have disappeared from the region and the old oak trees are dying.

FARMERS LOSING LIVELIHOOD

Local farmers and environmental NGOs have warned of water losses for more than 10 years but made a first, formal complaint to the European Commission in 2008.

In 2010, a 'non compliance' statement was issued against Poland for allowing a new KWB Konin mine, Tomisławice, in the eastern part of Wielkopolska.

According to the Commission, mining at Tomisławice has had an adverse impact on the area with farmers reporting crops affected.

"Less water means my income has been reduced to half since the mine is here. We are becoming poor," said farmer Józef Imbiorski, who lives a few kilometers from Tomisławice.

He said neighbors called him "the green frog" as he was the first, lone voice to complain about the mine. Now, he said, more farmers supported him as their land is also affected.

Maciej Muzykiewicz, whose 280-hectare farm lies just 800 metres from the Jóźwin mine, said he has also lost almost half his income as water levels have dropped and can now only plant seed once a year compared to twice previously.

"Surface waters are gone now .. so we have to rely on rain for farming, but that's not enough because it has been so dry with the climate changing," said Muzykiewicz.

KWB's Frąckowiak said the mines "certainly have an impact on farming land and its productivity" but stressed that the company abides by the requirements of Polish law.

"We pay fair reparations to the farmers to make up for the damage," he said.

Muzykiewicz, however, said claiming damages is complicated and only accessible to farmers like him with larger holdings and able to hire experts to show the link between mining and losses.

FROM FARMS TO INDUSTRY

In January this year, the Polish Ministry of Agriculture rejected a request by KWB Konin to turn farming land into industrial land in three areas, including Wilczyn where the company wants to open a new open pit mine.

But following an appeal by the company, the ministry has said it will re-assess its decision within weeks.

The Wilczyn Mayor, Grzegorz Skowroński, said he believed a new pit would "kill off" Lake Wilczynskie.

Pawel Kaczorowsky, a specialist with the Miradzskie forest service, an area also part of the Pojezierze Gnieznienskie Natura 2000 site, said a new mine just seven kms from the forest would have "devastating consequences".

"We are trying to take mitigation measures but the problem is huge. Trees die or are weakened and susceptible to woodworm attacks and the forest is more prone to fire," he said.

The vice director of Geological Concessions in the Ministry of the Environment, Rafal Misztal, told the Thomson Reuters Foundation that even if the Ministry of Agriculture decided in favor of ZE PAK, the law would not allow a new license to be issued if the local government vetoed the plan.

(Reporting by Claudia Ciobanu, Editing by Paola Totaro and Belinda Goldsmith; Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, trafficking, property rights and climate change. Visit news.trust.org).