What is the longest river that borders Bulgaria?
The Danube River
What do we call water stored underground in rocks and soil?
Groundwater
What type of climate does most of Bulgaria have?
Continental
What is one main use of water in households?
Drinking, cooking, cleaning
Which river runs through Sofia and provides water for the capital region?
The Iskar River
What type of groundwater rises naturally to the surface under pressure?
Artesian water
How does temperature increase affect river flow in summer?
It causes drying and lower water levels
What sector uses the most water in Bulgaria - industry, agriculture, or households?
Agriculture
Which large lake near Burgas is one of the biggest natural lakes in Bulgaria?
Lake Burgas
Which Bulgarian valley is famous for its hot mineral springs and thermal groundwater?
Sandanski–Petrich Valley
What mountain range is the source of many Bulgarian rivers?
The Rila Mountains
Why is water important for energy production in Bulgaria?
It’s used for hydroelectric power plants
What kind of surface water forms when rainwater collects in mountain valleys?
Lakes and reservoirs
What type of rock allows groundwater to move through cracks and holes?
Karst
How does deforestation impact Bulgaria’s water cycle?
It reduces rainfall absorption and increases erosion and floods
How do rivers support Bulgaria’s economy besides energy?
Transportation, tourism, and fishing
Which Bulgarian river flows south toward Greece and Turkey, helping irrigation in Thrace?
The Maritsa River
What is the name of the aquifer that supplies much of Sofia’s drinking water?
Sofia Valley aquifier
What major global issue threatens Bulgaria’s freshwater supplies through drought and irregular rainfall?
Climate change
Why is it vital to protect water sources from pollution?
Because clean water is vital for health, ecosystems, and sustainability