Simplify the following text for a Grade 4 native English-speaking person.
Original: The German government funded the construction of a water treatment plant with plans to process the city 's sewage and clean the Managua lake . Also pending is a mega-project to reconstruct the old center of Managua , and to introduce a monorail system , to alleviate future transportation problems in Managua .
Simplified: The city is located at the shore of Lake Managua .