1-ft Contours (2022)

This hosted feature layer has been published in RI State Plane Feet NAD 83 (2011). If feature service is unresponsive. We have provided a download link to the full geodatabase for the 1-ft 2022 contours. This is a 2GB file. Overview This feature service presents highly detailed 1-foot contour lines for the state of Rhode Island, derived from high-resolution lidar data collected in 2022. The contours were created under the RI Statewide Enhancements D24 project, which utilized lidar data with an aggregate nominal pulse spacing (ANPS) of 0.35 meters (approximately 8 pulses per square meter). The data adhere to the U.S. Geological Survey National Geospatial Program Lidar Base Specification, 2022 revision A. Contours are provided in a projected coordinate system using Rhode Island State Plane Feet (NAD83 2011) horizontally and are vertically referenced to NAVD88 with GEOID18. This precise topographic data supports a variety of planning, analysis, and management applications across Rhode Island. Feature Layer Topographic Contours (TOPO_Contours_01ft_2022): This layer contains 1-foot interval contour lines capturing terrain elevation variations statewide. Each contour feature is classified as either an index or intermediate contour type, with elevation values expressed in US survey feet. The dataset enables detailed terrain analysis, floodplain delineation, infrastructure planning, and environmental assessment activities. Geographic Coverage This dataset covers the entire state of Rhode Island, providing comprehensive elevation detail critical for state and local government, environmental agencies, and private sector stakeholders. Data Sources and Use Constraints The contour dataset originates from collaborations involving USGS, Fugro, and RIGIS, and is licensed under the RIGIS agreement. Users should note that data is provided "as is" without warranty and is intended for informational and planning use rather than legally authoritative surveying. Proper professional interpretation and verification are recommended for applications requiring high positional accuracy.本托管要素图层已采用罗德岛州平面英尺坐标系（NAD 83 (2011)）发布。若要素服务无响应，我们已提供2022年1英尺等高线完整地理数据库的下载链接，该文件大小为2GB。 ### 概述 本要素服务提供罗德岛州全境高精度1英尺间隔等高线，数据源自2022年采集的高分辨率激光雷达（Light Detection and Ranging, LiDAR）数据。该等高线数据集由罗德岛州全域提升D24项目生成，项目采用的激光雷达数据总标称脉冲间距（ANPS）为0.35米（约每平方米8个脉冲）。本数据集符合美国地质调查局（U.S. Geological Survey, USGS）2022年修订版A的《国家地理空间项目激光雷达基础规范》。等高线采用罗德岛州平面英尺坐标系（NAD83 2011）作为水平投影基准，垂直基准则采用北美垂直基准面1988（NAVD88）结合大地水准面模型18（GEOID18）。这套高精度地形数据可支持罗德岛州境内各类规划、分析与管理类应用。 ### 要素图层 地形等高线（TOPO_Contours_01ft_2022） 本图层包含覆盖全州的1英尺间隔等高线，用于表征地形高程变化。每条等高线要素均分类为计曲线（index contour）或间曲线（intermediate contour），高程值以美国测量英尺为单位。本数据集可支撑精细化地形分析、洪泛区划定、基础设施规划及环境评估等工作。 ### 地理覆盖范围 本数据集覆盖罗德岛州全境，提供完整的高程细节，对州及地方政府、环境机构与私营部门利益相关方均具有重要价值。 ### 数据来源与使用限制 本等高线数据集由美国地质调查局（USGS）、辉固（Fugro）及罗德岛州地理信息系统（RIGIS）合作产出，依据RIGIS协议进行授权。用户需注意，本数据按“现状”提供，不附带任何担保，仅用于信息参考与规划用途，不可作为具有法律效力的权威测量依据。对于要求高精度位置精度的应用场景，建议进行专业的解读与验证。