Surveys of Drainage Gates in Region 4, Guyana (Version 1)

Dataset documentation
Resource authors: Gregory Williams, Emad H. Habib, and Mohamed Morsy
HydroShare resource: https://www.hydroshare.org/resource/fca1ca19b9f748a2b90cf38b2effe549/
Project support: U.S. National Science Foundation, Award No. 2426270
Geographic coverage: Region 4, Guyana

Interactive map

View the interactive map of surveyed drainage gates in Region 4, Guyana

The interactive map displays the 67 surveyed structure locations and allows users to search for gates, filter by NDC area, and select map markers to view available survey attributes, including gate identifiers, invert elevations, opening dimensions, and field notes. The map is a visualization of the inventory; refer to the accompanying HydroShare dataset and the limitations documented below for research or engineering use.

1. Overview and intended use

This resource provides a georeferenced inventory of drainage gates in Region 4, Guyana. It contains 67 point records with structure identifiers, location information, number of openings, surveyed invert elevations, opening widths, and, where available, gate heights, road centerline elevations, and field observations. Some comments identify nonoperational structures, pumping infrastructure, or measurements requiring follow-up.

The inventory is intended to support drainage-system characterization, hydrodynamic and hydraulic model development, flood-risk assessment, infrastructure screening, and planning of future field verification. It is an infrastructure inventory, not a complete engineering design survey or a verified inventory of operational condition.

2. Data origin and preparation

The field surveys were commissioned by the University of Louisiana at Lafayette research project and performed by contracted local surveyors in Guyana. The survey information was subsequently assembled and made available by the research team in tabular (CSV) and geospatial (ESRI shapefile) formats.

Survey collection dates: April to June 2026

3. Files and data structure

The resource includes a CSV inventory and a point shapefile. A shapefile comprises several companion files, which must be kept together, including .shp (geometry), .shx (geometry index), .dbf (attributes), .prj (coordinate reference system), and .cpg (text encoding). A .qmd companion file is also included in the supplied set.

The supplied shapefile contains 67 point features. The supplied CSV contains 67 rows. Some shapefile fields are not represented in the simplified CSV; consult the shapefile for the additional fields and original comments. Field names may be truncated in the shapefile format.

4. Coordinate reference systems and elevations

• Shapefile point geometry: WGS 84 geographic coordinates, EPSG:4326, with longitude and latitude in decimal degrees, as specified by the .prj file.
• Eastings and Northings attributes: Projected coordinates in meters, consistent with WGS 84 / UTM Zone 21N (EPSG:32621) when compared with the shapefile point geometry. Original survey CRS to be confirmed with the survey contractor.
• Vertical datum: Surveyed elevation fields are reported in meters relative to Georgetown Datum (mGD).

Important for modeling: Georgetown Datum is a vertical reference and should not be confused with the WGS 84 horizontal coordinate reference system. Before combining surveyed elevations with a DEM, terrain surface, tidal boundary, or hydraulic model, verify that the vertical references are compatible or establish a documented transformation. The datum definition, benchmark realization, and any offset to other vertical datums are not supplied in this README.

5. Attribute guide

The following fields are present in the supplied shapefile. Descriptions marked for confirmation should be checked against the original survey deliverable.

The CSV uses some slightly different field labels, including Doors/Opening and Invert, mGD, and omits some shapefile attributes. Users should not assume that the two formats contain identical columns.

6. Completeness, uncertainties, and limitations

The inventory contains 67 records, but the coverage and detail vary among structures. In the supplied shapefile:

• Gate/opening heights are available for 6 of 67 records.
• Road centerline elevations are available for 10 of 67 records.
• Locality descriptions are missing for 32 of 67 records.
• Surveyor comments are present for 26 of 67 records.
• Some comments identify nonworking gates, associated pumping infrastructure, or values needing confirmation.

All 67 records have numerical entries in the invert-elevation and width fields. A populated number should not be interpreted as independent verification: at least some survey comments question specific dimensions or invert elevations. Review the original comments before using individual structures in model calibration or design decisions.

No comprehensive positional accuracy, vertical accuracy, benchmark documentation, survey date range, or independent quality-assurance report has been provided with this draft. The dataset should not be used as a substitute for site-specific engineering verification, especially for critical flood-control or operational decisions.

7. Recommended use in hydraulic and hydrodynamic modeling

For each structure used in a model, confirm its location, number of openings, opening dimensions, invert elevation, and operational configuration. Give particular attention to entries flagged in Comments. Reconcile the Georgetown Datum elevations with the model terrain and water-level boundary references. Where gate height or operational information is absent, document any assumptions made by the modeler.

The inventory does not, by itself, provide a complete representation of gate operation schedules, pump capacities, hydraulic coefficients, or all structure dimensions required for detailed hydraulic parameterization.

8. Versioning and citation

Version 1 represents the initial public inventory.