Early water-resources investigations in Collier County, Fla., were related to saltwater intrusion in Naples. With the advent of canal drainage and land reclamation farther inland, investigations were directed at effects of canals on water resources and the environment. High on the list of investigative needs are: (1) areal and vertical delineation of the shallow aquifer, the prime source of freshwater; (2) delineation of areas of poor quality ground water and the sources of the poor quality; (3) establishment of network of hydrologic data stations; and (4) determination of the relation between canals and the shallow aquifer. (USGS)