Managua waste water to a new water treatment plant at Las Mercedes in Eastern Managua in May 2009 relieved old concerns over water pollution and native wildlife, and brought some residents closer to the old city center and the rest of the mainland. Managua is located on the southern shores of Lake Xolotlán, also known as Lake Managua. Lake Xolotlán contains the same fish species as larger Lake Cocibolca in southeastern Nicaragua, except for the freshwater sharks found exclusively in the latter. Once a Managuan scenic highlight, the lake has been polluted from the dumping of chemical and waste water since
Managua central departments. This highway is commonly referred to as the "Northern Highway." The "Southern Highway", the southern part of the Pan-American highway, connects Managua to southern departments Carazo, Rivas and others. The "Carretera A Masaya" connects Managua to the departments of Masaya and Granada. The newly reconstructed "Carretera A León" connects Managua with León. All of these highways are in good condition, with little traffic congestion. Infrastructure on the highways is well maintained. This also tends to be true for cities and towns that are served or are in close distance with the freeways. However, this does not yield truthfully