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 as a source of water for the Kalayaan Pumped-Storage Hydroelectric Project in Kalayaan, Laguna. Other uses include fishery, aquaculture, recreation, food support for the growing duck industry, irrigation and a "virtual" cistern for domestic, agricultural, and industrial effluents. Because of its importance in the development of the Laguna de Bay Region, unlike other lakes in the country, its water quality and general condition are closely monitored. This important water resource has been greatly affected by development pressures like population growth, rapid industrialization, and resources allocation. Known lake islands include Talim, the largest and most populated island on the lake; Calamba