How NOAA Coast Survey streamlines workflows for vital navigation products
The NOAA Office of Coast Survey's newly revised hydrographic survey specifications and advanced toolsets streamline workflows, boost automation and enable seamless integration with the National Bathymetric Source (NBS) - Coast Survey's compilation of best-available bathymetry used across all navigation products. As a result, Coast Survey has driven consistent year-over-year reductions in the time required for data throughput. Final processing, packaging and delivery from field units to the shoreside branches is 65% faster in 2025 than in 2021, and data quality review and delivery from the branches to the NBS is 74% faster in 2025 than in 2021.
Coast Survey provides navigation products and services that support maritime commerce, keep people safe and secure and protect coastal environments. Timeliness is critical in meeting these objectives, which is why Coast Survey is committed to accelerating and optimizing the delivery of these products and services. It is imperative for Coast Survey to be able to rapidly ingest, qualify and integrate this data (measured collectively as 'data throughput') into navigation products and services. This data originates from hydrographic data collected not just by NOAA but also over 150 external data providers (comprising tens of thousands of individual survey contributions).
The comprehensive, multi-year overhaul of the hydrographic survey specifications and deliverables, or HSSD, published publicly in 2024 leveraged the use of S-100-based metadata and universal licence tags, enabling rapid and scalable data qualification and handling. The document also underwent a significant reduction in length (with a 53% reduction in page count), and was made more accessible through both PDF and online HTML formats.
To support the new HSSD, HydrOffice QC Tools 4 and other critical tools were released, with specifications and software co-developed to ensure optimal compatibility. Altogether, QC Tools 4 fully or partially automates ten distinct sections of the new HSSD. The development team continually receives suggestions and requests for additional automation from both NOAA users and the broader global user community.
Ocean mapping capabilities are continually evolving. The specifications that dictate these must - at the survey and product level - therefore also evolve. The HSSD represents NOAA's implementation of the International Hydrographic Organization (IHO) standards for hydrographic survey and product specifications. The fully revised HSSD, first published in 2024, marked the largest overhaul of the document in more than 20 years. This comprehensive rewrite ensures full compatibility with advanced, data-driven processes that embrace automation and standardization.
The new HSSD adopts S-100-based metadata attributes to describe data quality in terms of coverage, uncertainty and feature detection. This metadata framework has been incorporated throughout the entire Coast Survey workflow, ensuring seamless consistency and compatibility from specification to final product. As a result, the requirements, evaluation, ingestion and synthesis of bathymetric data for product creation are all accomplished in the same S-100 metadata framework, eliminating the need for metadata translation or conversion at any stage of the workflow.
Coast Survey ingests vast amounts of data generously contributed by external providers, who range from other NOAA offices and federal partners to regional and state initiatives, universities, private sector surveyors, port authorities and beyond. Thus, it was imperative for data sharing to become much more simplified. Traditional models that relied upon custom legal agreements were laborious, time-consuming and often did not sufficiently clarify terms for third-party use. The modernized data sharing approach in the new HSSD embraces the use of universal data licences, wherein a data provider applies a well-known and recognized licence to their data. This ensures that Coast Survey and all third-party users are properly informed of the terms of use, without requiring any meetings or legal reviews. The known licence terms enable automated handling of the data - recognition of the licence makes it 'machine readable'; that is, an automated process was built and implemented to handle data under the known licence type. This shift makes data sharing and data handling vastly more simplified, streamlined and scalable.
To further facilitate data contributions from external providers, the new HSSD provides a general framework for submitting data of all types to Coast Survey, not specific to any type of sensor, and not restricted to any type of survey (e.g. safety of navigation surveys). Ideally, this opens the aperture for more external data submissions by clearly defining minimum submission requirements alongside what is maximally expected of a hydrographic survey conducted for safety of navigation. Additionally, the S-100 metadata framework in use has the attributes 'decoupled' for a more flexible data qualification. For example, the lack of uncertainty calculations in an external data submission would not by itself degrade the feature detection capabilities exhibited or the bathymetric coverage achieved in a survey.
The HSSD document itself was made much more concise, and reduced to focus solely on technical specifications. Guidance, procedures and best practices (which had accumulated over the years in the legacy HSSD) are instead maintained in more applicable references (e.g. Standards of Ocean Mapping Protocol, Field Procedures Manual and vendor documentation). This results in a more focused document that is not redundant with other resources, and it is easier for users to find the information they need. Additionally, the HSSD is maintained in Adobe RoboHelp, which offers one-click export to both PDF and HTML versions, the latter of which offers a wiki-like experience to view NOAA hydrographic specifications. Because of the rapid update capability, new HSSD versions are released on an as-needed basis, and potentially midseason, to disseminate critical information to surveyors.
Following a guideline of letting digital data speak for itself as often as possible, without human encroachment, reporting requirements in the new HSSD were substantially reduced from the legacy version. Initially, only an XML metadata file was produced; however, in response to user feedback, a more human-readable PDF report has since been added. Despite this addition, the reporting requirements remain intentionally minimal, aligned with Coast Survey's data-driven and streamlined approach. Prose is limited to aspects that cannot be directly inferred from data or metadata. This balance is still being refined, however, and working groups within NOAA are actively engaging with surveyors and end users to determine the best equilibrium between a traditional descriptive reporting style and an automated XML metadata output.
HydrOffice QC Tools is a long-standing collaborative effort between Coast Survey and the Center for Coastal and Ocean Mapping and Joint Hydrographic Center (CCOM/JHC) aimed at automating compliance with NOAA hydrographic specifications and, more broadly, identifying common data quality issues across the hydrographic community. The release of QC Tools 4, a major version update, was strategically aligned with the debut of the overhauled HSSD in 2024, ensuring full compatibility with the new specifications. Other critical tool updates supporting the new HSSD were released at the same time by Coast Survey developers, and these included Charlene (for automated data transfer and processing), Scribble (for automated survey metric reporting) and xmlDR (for streamlined survey metadata generation). The co-development of these tools alongside the new specifications, combined with real-time field testing, provided critical feedback loops between writing teams and software developers, to ensure the new specifications effectively support automation.
QC Tools 4 serves as the primary tool to ensure compliance with the HSSD. Within its parameters, a user may set the NOAA quality metrics as defined in the new HSSD, which in turn govern the evaluation criteria of the various automated checks. As with previous versions, QC Tools 4 assesses the core deliverables of a hydrographic survey: bathymetric grids, feature files and the submission folder structure. A list of QC Tools 4 features and functionalities are outlined below (and shown in Figure 3):
Bathymetric Attributed Grids (BAGs), developed by the Open Navigation Surface Working Group (ONSWG), are required deliverables under the new HSSD, and serve as the primary input format into the NBS. Consequently, recent development in QC Tools 4 has placed particular emphasis on BAG Checks, which evaluates BAGs to ensure compliance with the HSSD and their seamless ingestion into the NBS. A list of BAG Checks functionality is outlined below.
BAG Checks offers two profile settings: a 'General' profile, aligned with the ONSWG BAG specification, and a more comprehensive 'NOAA NBS' profile, which enforces the NBS requirements and flags individual nodes that fail any of the checks.
The NBS has ingested roughly 2,800 BAGs since 2018. NBS data is available to the public as BlueTopo, which is the best-available bathymetry as determined from survey dates and the various metadata attributes (e.g. coverage, uncertainty and feature detection) that are available at each node. BlueTopo is served from NOAA's nowCOAST, a cloud-based web mapping GIS portal for real-time meteorological and oceanographic data (see Figure 4). BlueTopo is currently available in all US East Coast, Gulf and Caribbean waters, with the Pacific, West Coast, Great Lakes and Alaska regions to be built out in 2026.
In 1967, HydroPlot, the first fully automated system for hydrographic data collection and processing, was installed on the NOAA Ship Whiting. Since then, Coast Survey has consistently harnessed the power of computing to streamline and enhance hydrographic operations. With advancements in hardware and software capabilities, Coast Survey's tools evolved accordingly, with Shipboard Data System (SDS) in the 1980s, Hydrographic Data Acquisition and Processing System (HDAPS) in the early 1990s and Pydro in the early 2000s. The current ocean mapping tools developed by CCOM/JHC and NOAA (freely available via the open source Pydro and HydrOffice suites) have been instrumental in enhancing hydrographic workflows.
Coast Survey developers work relentlessly to replace tedious and manual processes with automated workflows, bridging gaps where commercial software lacks the flexibility required to meet Coast Survey's needs. This continuous focus on streamlining reflects a well-established culture within Coast Survey; one that was firmly in place long before the publication of the new HSSD in 2024.
Since its introduction in 2015, HydrOffice QC Tools has seen widespread adoption within NOAA and beyond. It has delivered significant benefits, notably bringing much-needed consistency in the review practices between ship and shore. It has also helped define a clear 'finish line' for review tasks, that otherwise is not easy to define. Additionally, it has proven to be highly valuable as a practical tool for familiarizing new personnel with hydrographic survey specifications. Similarly, Charlene, a tool first released in 2016, has revolutionized data management and processing in Coast Survey. By automating workflows and minimizing human error, Charlene has led to substantial improvements in data quality. In 2022, the Hydrographic Data Review (HDR) process was launched at Coast Survey's shore-based processing branches, resulting in a much leaner and more efficient workflow that substantially reduced review times. In 2024, Field Project Instructions (PI) were also overhauled to fit within the adopted HSSD metadata framework. The HDR and PI (as well as numerous other reporting mechanisms) are fully supported in xmlDR, a long-standing and essential component of the Pydro suite of tools.
With the new HSSD as the foundation for streamlined, data-driven workflows - and tailored toolsets delivered to support them - Coast Survey has drastically improved the speed and efficiency of hydrographic data throughput. This advancement enables the timely ingestion of high-quality data into the NBS and, ultimately, to NOAA's end users. Aligned with a broader organizational commitment to streamlining, these efforts set a clear trajectory for ongoing workflow optimization, greater scalability and a future-ready navigation product pipeline.