Bureau of Topographic and Geologic Survey
Gone Fishing . . .
Have you done any fishing or recreational boating in our state parks? The Pennsylvania Geological Survey has just released bathymetric (water-depth) maps for 18 state park lakes that should be of interest to all the anglers and boaters out there. The maps, part of the Survey’s open-file miscellaneous investigations, are the result of data gathering that began in January 2005. They were created in large part through the efforts of staff geologist Rose-Anna Behr (the lady in the stern of the boat shown at the top of this page).
Depth and location readings on the lakes were obtained with a Garmin 3006C integrated depth finder and GPS. Back in the office, the data was imported into an ArcGIS file geodatabase, and ArcMap was used to create a contour map of lake depths. PAMAP orthoimagery was the base map for most of the surveyed areas.
In addition to water depths, the maps display fish-friendly structures, such as stumps or downed trees, and amenities, such as boat ramps, concessions, and restrooms. Please keep in mind that although the maps are meant to assist boaters and anglers, they were not designed for navigation. Lake depths can change due to drawdown, flooding, and siltation, and fallen trees and other debris may have moved since the data were first collected.
The 18 park lakes with published maps and 2 more lakes whose maps will be released in the near future are listed on the web page titled Bathymetric Maps for Lakes in Pennsylvania State Parks. An article on the bureau’s foray into bathymetry, associated field techniques, and the initial purpose of the research can be viewed in Pennsylvania Geology, v. 35, no. 1, p. 10–12.