Laguna (province) producing of fish. Carp and tilapia fingerlings are also being grown in inland ponds and freshwater fish pens. There are a total of 457 operators utilizing an area of for fish pens and fish cages. Aside from the Laguna de Bay, approximately 12% of the area in the Seven Lakes of San Pablo is being used for aquaculture. Laguna is home to twenty-one economic zones as registered under the Philippine Economic Zone Authority. Most of these economic zones are located in Santa Rosa, Biñan, and Calamba. The largest economic zone in Laguna is the Laguna Technopark, located in Santa Rosa
Laguna de Bay The lake is a multipurpose resource. In order to reduce the flooding in Manila along the Pasig River, during heavy rains, the peak water flows of the Marikina River are diverted via the Manggahan Floodway to Laguna de Bay, which serves as a temporary reservoir. In case the water level on the lake is higher than the Marikina River, the flow on the floodway is reversed, both Marikina River and the lake drain through Pasig River to Manila Bay. The lake has been used as a navigation lane for passenger boats since the Spanish colonial era. It is also used