Making data available in support of the blue economy, one step at a time

The Canadian Hydrographic Service (CHS) recognizes that knowledge of the seafloor is required for a  multitude of reasons; from scientific research to commercial applications and beyond, these reasons are why CHS is committed to collecting and sharing quality bathymetric data. 

On Sept. 24, 2020 CHS made a significant step forward in sharing a consolidation of its bathymetric data holdings for non navigational purposes, providing key information in support of the Blue Economy. Bathymetric data is  represented from all available methodologies and technologies—everything from lead line, single and multibeam sonars, to bathymetric LiDAR, with the most modern and technologically advanced taking precedence in areas of overlap. 

The CHS’ NONNA-10 data series represents a 10-fold improvement over its predecessor, the CHS NONNA-100 data series, which was released two years earlier. “NONNA” refers to NON-NAvigational, and the 10 or 100 references the approximate resolution of the data in meters.

In addition, CHS introduced the CHS NONNA Data Portal, to facilitate access to the CHS NONNA data. Users can view, query and download data directly from the portal. The CHS NONNA data are accessible free of charge via the data portal, both to view or download in various formats: 32-bit GeoTIFF, ASCII++, CSAR, and BAG. Since the September launch, the portal has enabled users to download over 84,000 CHS NONNA-10 products! 

Access to the CHS NONNA data supports a broad range of scientific activities including but not limited to: 

• Geographical planning for activities such as identifying areas for resource exploration or  environmental protection, or supporting the protection of Species At Risk.

• Numerical modelling to simulate habitat mapping or nutrient and sediment transport.

• Informing policy and program development for a wide variety of marine-related activities.

• Broader scientific research concerning ecology, climate change mitigation, and  geomorphology. 

Please visit the Government of Canada’s Open Data site for more information about the data and to access  the products. The CHS NONNA Data portal is currently a pilot project and as such, we encourage you to  provide feedback on your user experience and how you are using the data, such that we may meet your specific requirements even better going forward. 

The future of hydrography is digital, and the CHS NONNA data series is one small transformative step for  the Canadian Hydrographic Service in that regard. 

The Canadian Hydrographic Service lets its first contract solely for the provision of ASV-based hydrography

In July 2020, the Canadian Hydrographic Service (CHS) solicited interest, through Public Services and Procurement Canada’s Hydrographic Services Supply Arrangement, to conduct a multibeam survey in Lake Superior. But this wasn’t just any contract for the provision of hydrographic services. Rather, there was one caveat that made this solicitation different from any others to date. The statement of work for this contract stipulated that the service provider must use commercial off-the-shelf autonomous technology instead of a conventional survey launch or ship.

The focus area of this survey was a 7.5 km by 100 km portion of a secondary low impact shipping corridor directly south of Thunder Bay, abutting the US border. This location was used to simulate an Arctic shipping corridor, for future plans to utilize autonomous vessels in the Canadian Arctic. Depths within the area ranged from 30m to 300m. Of note, this area also coincides with a portion of the world’s largest National Marine Conservation Area.

These ASVs are the approximate size of a car and roughly 750 kg each. They were remotely monitored and controlled 24/7 via a satellite connection from various locations in Europe, by both ASV pilots (for navigation) and hydrographers (for data collection/data quality review). A minimal field staff component was on-site in Thunder Bay for data retrieval, ASV maintenance and support.

Of keen interest to the CHS was the ability for the ASV to employ ‘auto-swath’ technology, allowing automatic line adjustment in response to changing water depths. The use of auto-swath technology is instrumental in efficient multi-beam data collection. The lakebed in this area was relatively unknown, being last surveyed in the mid 1970’s, using single beam technology with 500m line spacing.

The CHS is hoping to leverage this experience going forward, taking several recommendations into account such that ASV technology may reach the level of maturity required for full implementation. One specific area of focus will be to evaluate the feasibility of adding payloads to the ASV in order to support additional in-situ marine science.

Not only will this modern dataset allow the CHS to update its navigational products in the area, it will also be consolidated into CHS’ NONNA-10 and NONNA-100 data series, available for free download in support of a broad range of non-navigational uses.

Shipwreck City of Genoa examined by ultra-high resolution underwater lidar in southern Lake Huron

In support of Lakebed 2030, GLOS tasked the crew with both a surface survey using ship-mounted sonar and an ultra-high resolution laser survey using a remotely operated vehicle (ROV). Laser surveys represent a type of newer mapping technology that can improve understanding of underwater features and benthic habitats by creating extremely detailed 3D images. 

The test site for this mission was in southern Lake Huron where the ill-fated City of Genoa steamship was hauled after wrecking in 1911 near Sarnia, Ontario.

Over the course of three days and 27 surveying hours, the team collected high-resolution sonar data of the lakefloor using an R2 Sonics 2420. 

The ROV was fitted with a laser scanner: a ULS-500 from 2G Robotics.

Several recent advances in coastal surveying can improve speed, accuracy, and cost

By Ethan Theuerkauf
Assist. Professor at Michigan State University

In the old days it took a survey crew on shore and on a boat many hours to acquire nearshore survey profiles that mapped the top of the bluff or dune to offshore beyond the depth of closure. In addition, once back in the office, much more work was required to process those data. That has now all changed. 

The shore crew is now one person outfitted with a high-accuracy GPS system and a drone and the boat crew is now one person on a personal watercraft (PWC). In addition, the shore and water parts of the survey no longer need to be conducted simultaneously—they can be combined together using computer programs back in the office. Surveying with these new technologies was ten times faster than the methods used in historical surveys, which allows more frequent monitoring of larger stretches of the coast.

How does it work? The coast shoreline portion of the survey utilizes a quadcopter drone with a camera to collect a series of photographs over the study site. Throughout the site about a dozen black and white targets known as ground control points, are placed through the study area and surveyed with a GPS.  These are used to turn the photos collected with the drone into centimeter-accurate 3D maps of the beach, bluff, or dune. From here, a profile can be extracted and compared to the historical data collected by Dr. Meadows since the 1980s.

The end result is an integrated digital beach and bluff and an offshore profile. During this current episode of high Great Lakes water levels and rapid coastal change, we have found that this rapid, accurate, and cost-effective method of tracking coastal change is extremely beneficial for generating important datasets for coastal research and management.

NOAA will continue efforts to close the Great Lakes hydrographic data gap this year

By LCDR Charles Witsotzkey
NOAA Navigation Manager for the Great Lakes Region

Several recent mapping missions from NOAA’s Office of Coast Survey have brought the region closer to closing the hydrographic data gap, with two large, traditional contract surveys planned for later this year. 

One will focus on southern Green Bay, WI (Project OPR-Y390-KR-21) and another near  Whitefish Point in Lake Superior (Project OPR-Z394-KR-21). The two project areas are shown below, along with an underlay depicting OCS Hydrographic Health Model priority areas. The model is a quantitative risk-based assessment used to inform survey prioritization. Coast Survey considers both local requests and the hydrographic health model when determining project areas.

The southern Green Bay project will address known and suspected chart discrepancies, provide baseline environmental data for the proposed Green Bay National Marine Research Reserve, and directly support a University of Wisconsin - Madison research into the prevalence and sources of PFAS Chemicals in the Green Bay ecosystem. 

In the northern half of Green Bay, NOAA continues to evaluate data from a recently-completed contract that used state-of-the-art Satellite Derived Bathymetry methods to obtain usable depth data for charting applications. Coast Survey and the National Geodetic Survey’s Remote Sensing Division completed the contract. Preliminary results indicate that the new methods will be useful for obtaining near shore bathy data in areas with high levels of water clarity. 

This year’s Whitefish Point project will support the update of nautical charts for an important commercial shipping area. 

Coast Survey’s recent surveys near Chicago in 2020 (Project OPR-Y395-KR-20) and the Straits of Mackinac in 2019 (Project OPR-X388-KR-19) are still in the Coast Survey quality control process. The Chicago data was recently delivered to the quality control branch, and it will likely be 12-18 months before the data starts to be delivered to NOAA’s National Centers for Environmental Information (NCEI). 

Processing the Straits of Mackinac survey has been delayed somewhat due to competing high priority projects and consultations with various authorities to ensure sensitive data is managed properly. This survey data is presently beginning to be transmitted to NCEI. 

Prioritization analysis currently underway to pinpoint important areas for future surveys

Last July, a region-wide prioritization effort kicked off, reaching out to over 400 stakeholders to determine the areas in most need of lake bottom surveys, and the responses are in.  

After compiling the data from the dozens of responses from participants who were provided by lakewide action management plans (LAMPs) and the Coastal States Organization, organizers will publish a report, making the findings available to the public. The goal is that the report will help inform the location and methods for future surveys for maximum benefit to the stakeholders spanning federal, state, tribal, academic, and nonprofit organizations. 

Part of the national IWG-OCM study, this prioritization effort was funded by the Great Lakes Restoration Initiative (GLRI) through the U.S. Geological Survey. The Great Lakes Observing System collected responses using the NCCOS Spatial Prioritization Widget, a participatory GIS, created by NOAA National Centers for Coastal Ocean Science (NOAA NCCOS).