| | 132 |
| Study Name: | | Survey Type: |
| NLDS-1985-86 | | Bathymetry |
| Survey Name: |
| NLDS-1985-86 MASTERDelNorte Bathymetry | | Disposal Site: |
| | NLDS (1977-1995) |
| | Start Date: | 7/1/1986 | End Date: | 7/14/1986 | Collector: | | SAIC |
| Process Description | Analysis of the bathymetric data standardizes the raw depth values to Mean Low Water by |
| | correcting for the depth of the transducer and for tidal changes during the survey. |
| Logical Consistency | The precise navigation required for all field operations was provided by the SAIC Integrated |
| | Navigation and Data Acquisition System (IDAS). This system uses a Hewlett-Packard 9920 Series |
| | computer to collect position, depth, and time data for subsequent analysis as well as provide real- |
| Attribute Accuracy | Bathymetric surveys are conducted using an integrated navigation system and a Hewlett-Packard |
| | 9920 Series computer to collect position, depth, and time data for subsequent analysis as well as |
| | provide real-time navigation. Depth measurements collected during this survey were made using a |
| | Raytheon DE-719B Precision Survey Fathometer and a model SSD-100 depth digitizer. This system |
| | operates at a frequency of 208 kHz and measured depth to a resolution of 3.0 cm, with an accuracy |
| Horizontal Accuracy | Horizontal positions were determined to an accuracy of +/- 3 meters from ranges provided by a Del |
| | Norte Trisponder System. Shore stations were established over known benchmarks. |
| Vertical Accuracy | Depth measurements collected during this survey were made using a Raytheon DE-719B Precision |
| | Survey Fathometer and a model SSD-100 depth digitizer. This system operates at a frequency of |
| | 208 kHz and measured depth to a resolution of 3.0 cm, with an accuracy of +/- 10 cm at these |
| Depth Datum Name | Mean Low Water |
| Depth Distance Units | cm |
| Use Constraints | This data was collected and processed for a specific U.S. Army Corps of Engineers activity and |
| | indicates the general existing conditions at the time of collection. As such, the data are only valid for |
| | their intended use, content, time, and accuracy specifications. The user is responsible for the |
| | results of any application of the data for other than the intended purpose. |
| Contact Person | Tom Fredette, Ph.D. Program Manager, US Army Corps of Engineers, New England District |
| | 696 Virgina Road, Concord, MA, 01742-2751, Phone:(978) 318-8291 Fax:(978) 318-8303 |
| | thomas.j.fredette@usace.army.mil |