NOAA RNC Tile Service displays first ENC-only product

NOAA Office of Coast Survey released its 1:12,000 electronic navigational chart (NOAA ENC®of the Merrimack River, Massachusetts, in the RNC Tile Service. This is the first time a navigational chart—created solely as ENC product—is included in the tile service. The tile service renders a traditional depiction of the nautical chart for use with GPS-enabled electronic chart systems or other “chart plotter” display systems to provide real-time vessel positioning for recreational mariners. This chart is included in the single chart tile sets and the quilted tile sets both in the online and offline versions.

The Merrimack River, located in Massachusetts, is just south of the New Hampshire border.The single chart tile set is named​ 13274K0000_1.
The Merrimack River, located in Massachusetts, is just south of the New Hampshire border. The single chart tile set for this area is named​ 13274K0000_1.

The tile service version of the Merrimack chart retains the look of a NOAA paper chart but is derived from the ENC charting database. This gives users the opportunity to use ENC-only data with a traditional NOAA chart feel. NOAA intends to incorporate all future charts that are produced only as ENCs into the tile service (ENC-only charts are outlined in the National Charting Plan, page 25).

“This release represents a major milestone in nautical charting,”  said Rear Admiral Shepard Smith, the director of Coast Survey.  “This is the first chart that was digital from its inception, breaking with the longstanding practice of digital charts based on paper charts.”  

For professional mariners, it is important to note that there is no paper chart equivalent, and that this chart will not be served by the Notice to Mariners systems provided by the U.S. Coast Guard and National Geospatial-Intelligence Agency.  Updates will be made as necessary by NOAA weekly.  Customers with compatible applications will get the updates automatically.

The original 1:12,000 ENC of the Merrimack River was released at this time last year. Recognizing the need for a more detailed chart, a group of local and state stakeholders concerned with the economic revitalization of the area contacted NOAA to create a new, larger-scale chart. The new, larger-scale ENC was compiled using U.S. Army Corps of Engineers data, NOAA lidar data, and privately funded survey data. When shown in detail, the combined data provides mariners with a clearer picture of the overall conditions and dangers to navigation. The availability of this chart in the RNC tile service provides mariners greater flexibility in viewing the chart.

This update to the RNC tile service also includes the ArcGIS Tile Metadata Service, adding support for source chart metadata from within ArcMap and other GIS applications. Instructions for loading the tile metadata into ArcMap have been added to the developer’s website.

merrimack-tileservice3
Instructions for loading tile metadata into ArcMap are available from the tile service website.

The ArcGIS Tile Metadata Service can be accessed from a web application, as shown below in our ArcGIS sample viewer for the quilted tile set.

merrimack-tileservice4
ArcGIS sample viewer for the quilted tile set.

 

 

NOAA surveys for recreational boat traffic safety in Tampa Bay

NOAA’s navigation response team 2 (NRT2), homeported in Fernandina Beach, Florida, conducted a survey around the Sunshine Skyway Bridge, which spans Tampa Bay. The U.S. Coast Guard (USCG) and additional members of the Tampa Bay Harbor Safety Committee requested the work and expressed interest in establishing alternate routes for recreational boating traffic. Alternative routes will alleviate increasing congestion where the main ship channel passes beneath the bridge. This area is naturally restrictive to navigation and, as a result, there have been multiple accidents and near accidents here in the past.

Multibeam echo sounder coverage. Credit: NOAA
Multibeam echo sounder coverage. Credit: NOAA

Lt. j.g. Patrick Debroisse from NOAA Research Vessel Bay Hydro II installed a topographic lidar system on NRT2, which marked the first time a lidar system was employed from an NRT boat. The lidar system enabled 3D data to be collected for those portions of the bridge that are above water line. NRT2 collected lidar data for associated bridge protective structures and two fixed light range towers in addition to the bridge and bridge supports.   

The accurate positional and dimensional information gleaned from this data will be used to compliment extensive hydrographic sonar data collected beneath the surface. Together, the complete data set will enable full consideration of area features, both above and below the water line, in determining the placement of alternative routes.

TampaBay_SunshineSkywayBridge

The center spans of the Sunshine Skyway Bridge (left) were successfully captured from lidar data (right). Photo credits: NOAA
The center spans of the Sunshine Skyway Bridge (above) were successfully captured from lidar data (below). Credits: NOAA

A USCG approval decision is anticipated in the spring. If approved, the chief of the cartographic team will work to have the alternate routes added to all affected NOAA charts.

The NRT2 team consists of James Kirkpatrick (team lead), Lucas Blass, and Howie Meyers. NOAA’s NRTs operate trailer-able survey launches to provide time-sensitive information during emergency response and maritime incidents such as vessel groundings, sinkings, or cargo loss. The launches are equipped with multibeam and side scan sonar, which can help identify navigation hazards and mitigate risk to life and property.

The largest scale raster navigational charts of this area, charts 11415 and 11416, are available online.

NOAA Ship Fairweather uses new technology to improve survey efficiency

By ENS Peter Siegenthaler

Following the scheduled winter repair period, Fairweather is kicking off the 2017 field season in Tlevak Strait; the waterway between Dall Island and Prince of Wales Island in Southeast Alaska. This area was last surveyed between 1900 and 1939, and the lead-lines used at the time to determine depths were susceptible to omission of rocks and other features in an area. Using the latest innovations in hydrographic technology, Fairweather will be resurveying these areas with complete coverage multibeam echo sounder bathymetry. This allows Fairweather to identify any rocks or shoal features missed in prior surveys, increasing the safety for local communities, whose economies and livelihoods are dependent on maritime transportation of goods.

One of the new developments Fairweather’s survey department in particular is excited about is a new software program affectionately named “Charlene.” Charlene was developed by PS Eric Younkin at Coast Survey’s Hydrographic Systems and Technologies Branch (HSTB) to automate the night processing workflow. This simplifies hours spent each night converting and correcting raw sonar data into an automated script which takes in raw data at one end and generates products at the other. Initial results are promising, and the ship is looking forward to fully integrating Charlene into the processing workflow.

Another new development for the 2017 field season is new multibeam sonars for the ship’s survey launches, which were installed during the winter repair period. The preliminary data acquired by these sonars has shown vast improvement over their predecessors’ data, which will go a long way towards reducing data processing timelines. The new sonars do this by automating most of the acquisition parameters in real-time, far faster and more effectively than could be achieved manually. They also take advantage of a multitude of hardware and software advances that have taken place over the past several years, resulting in systems that are quieter, smaller, and easier to operate.

Fairweather is continuing to use and develop the launch-mounted lidar systems (lasers) for the acquisition of shoreline data. This was another HSTB-developed process that was validated during the 2016 field season. This year, Fairweather is using those lessons learned in order to further improve our acquisition workflow. These systems create accurate real-time point clouds of features above the waterline and have revolutionized the way hazards to navigation are documented. Before the use of lasers, shoreline verification frequently required physically touching rocks and obstructions above the water surface for accurate measurement and placement. This process involved increased risk, took more time, and produced less accurate data. The new laser workflow addresses all these limitations. By scanning the shoreline at a distance with calibrated equipment, efficiency, accuracy, and safety are all greatly improved.

Overall, Fairweather is enthusiastic about being back at work in Alaska. With her new software, sonar systems, and dedicated crew, the stage is set for and productive field season!

Area surveyed by Fairweather May 30- June 10, 2017.
Area surveyed by Fairweather May 30- June 10, 2017.

NOAA survey ships adopt laser scanners to improve safety at sea

How tall is that rock, really? Is that islet charted correctly? Mariners will have greater confidence in the location and height of charted features as NOAA’s hydrographic ships increase their use of newly adopted laser technology to measure and locate topographical features like rocks, islets, and small islands.

Recently, Lt. j.g. Patrick Debroisse, junior officer on NOAA Ship Fairweather, trained his NOAA Ship Rainier colleagues on how to use the topographic laser that they will soon be receiving.

Fairweather used this laser throughout this past season for feature attribution, and I was tasked with creating the procedures and training other ships,” Debroisse reports. “Rainier will be the next ship to receive the lasers, followed by the East Coast ships [Thomas Jefferson and Ferdinand R. Hassler].”

laser image of NOAA ships
Laser image of NOAA Ships Fairweather, Rainier, and Shimada moored at Marine Operations Center – Pacific, acquired during training

 

NOAA charts features such as rocks, piles, islets, kelp beds, and buoys, to give the mariner a clear picture of the dangers that could be in the area. Along Alaska’s and Maine’s rocky shores, for instance, features can be especially important because the tide ranges can be large. It’s especially important to accurately measure a rock at low tide, so a mariner will know its depth when they can’t see it at high tide.

Features on chart 16604
This area on chart 16604 illustrates features that could use the precision of topographic laser scanning.

 

Charted features are also used for visual points of reference during navigation.

Until recently, hydrographic ships’ launches were used to locate the features. To get a reasonable location, the launch would carefully approach the rock or other feature, and “kiss” it with their bow. They would then add the five feet from the boat’s GPS unit to the feature, and mark it on their field hydrographic sheets for use by the cartographers. If the seas are too heavy, or the area too rock-strewn, the surveyors stand on the ship or shore, and use a hand-held laser range finder to measure the height and distance of the feature, and then note the time so it can be corrected for the tide.

One of Rainier's four launches at work in Uganik Bay.
One of Rainier‘s four launches at work in Uganik Bay.

 

This laser technology will be safer than using a launch, and more precise than is possible with the human eye. The laser uses focused light to find and place objects accurately, similar to the way sonar is used to find the seafloor. The laser head produces sixteen laser beams, which reflect off the target object and are received back by the laser head. The computer then uses that data, along with precise positioning and attitude (roll, pitch, and yaw — or orientation) data, to determine the height and location of the object.

These infrared lasers are invisible and completely safe to the eyes of humans and any animals in the area. Also, unlike airborne lidar units that obtain shallow water bathymetry, the ships’ laser cannot penetrate the water.

Fairweather worked with the Coast Survey Development Lab to test this laser scanner, to determine its feasibility as a topographical tool in the Alaskan environment,” Debroisse says. “We found that this laser method increased the speed and accuracy of data acquisition, and increased the safety of the boat crews completing these surveys.”

And safety, after all, is important for everyone from the NOAA charting teams to the millions of chart users.