Hydrographic Surveying deals with the measurement and description of the physical features of water and their littoral or shore area. Essentially, Hydrographic Surveying is the topography of the bottom of lakes, streams, rivers and the ocean.  They are used to determine the depth of river channels, to aid in navigation, to determine the location of underwater rocks or obstructions, to determine the amount of sediment on river or ocean floors, and to calculate the volume of dredging or filling operations among other uses.

Sometimes referred to as Bathymetric Surveying when performed in an ocean environment, the techniques for data compilation and mapping are essentially the same.

Pennoni Associates’ Hydrographic Surveying teams are equipped with Innerspace Technology dual frequency sounding systems, models 620 and 486. These systems are Windows XP driven and consist of a dual frequency sounding unit which allows our survey teams to determine the depth of sediment thanks to the delivery of the sound at different frequencies, an ITI data log with guidance (DLWG-XP), hydrographic software and a DGPS/RTK receiver. We marry this with our survey-grade Leica 1200 GPS equipment for obtaining RTK information. This hydro equipment is mounted to our surveying vessels, ranging from a small 14-foot aluminum Jon boat for small lakes and streams to a larger 26-foot  deep V aluminum Work skiff with 135hp outboard motors for larger river or ocean projects.

Pennoni’s survey personnel have both 40-Hour OSHA Hazwopper and 10-Hour OSHA Safety Training, CPR and First Aid Training, and TWIC credentials. 
 

Pennoni Associates maintains an in-house staff of trained and experienced underwater inspection team leaders and diving personnel, including licensed professional engineer divers. Our crews routinely perform underwater inspections and hydrographic investigations for both public and private clients. By maintaining all aspects of our projects in-house, our project managers are better able to maintain quality control, schedule, and budget for each assignment.

Our staff has a sound understanding of both engineering principals and diving technology, enabling us to provide our clients with safe and comprehensive underwater operations. Our inspection documentation provides our clients with detailed information to allow for informed decisions regarding safety and structural rehabilitation issues.  Pennoni is also equipped to provide additional engineering services that may arise from the inspection effort such as structural analysis, rehabilitation alternatives, computer aided design and drafting, cost estimating, and construction management.

Underwater inspections are performed in accordance with OSHA requirements utilizing certified and experienced personnel.  Our teams are equipped with surface-supplied hardhat dive gear, which permits diver-to-surface communications as well as safety and protection on construction sites, or at sites with contaminated conditions.  Pennoni also has a complete array of support equipment available such as dive and survey vessels, underwater video and photography, ultrasonic measurement units, and recording fathometers for performing hydrographic investigations.