Evaluating Rapid Mapping Elements

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Qui non est hodie cras minus aptus erit. – Ovid
He who is not prepared today will be less so tomorrow.

Mapping is an essential tool in evaluating post-event conditions and planning for response and recovery; this reality is nothing new. And in recent years of preparing for the unthinkable, the overall readiness for a wide range of disasters, emergencies, and otherwise time-critical situations has been given well-deserved and often long overdue priority consideration.

The greatest priority has rightfully been given to providing training and resources for first-responders. Though not traditionally regarded as first-responders, surveyors and field mapping personnel have seen very visible examples of how important and sometimes critical their roles are in rapid response situations. Natural disasters, mining crises, accidents, environmental hazards; headlines for each come readily to mind, and the role of mapping in their resolution.

Rapid Mapping Elements, or RMEs, are the resources available to respond with rapid site condition mapping products. These include equipment, systems, hardware, software, and available trained personnel that may be activated in rapid response to such events. Evaluating each element, providing contingency plans for a wide range of events, testing and training need not be a costly exercise, and preparing for the infrequent and unlikely can improve day-to-day operations.

Contingency planning for many local communities has become a daunting task. Budgets are already tight, and the irony of the trend for shrinking emergency planning budgets has enraged many, especially first-responders. Simply waiting for federal funding for the less visible aspects of emergency planning is not prudent; many local communities and related industries have become proactive in these efforts.

The surveying community can provide a great service by evaluating the RMEs in local communities and work with the emergency response planners in developing contingency plans. In many places this outreach has already taken place. Commercial interests were quick to respond. At the ESRI International GIS conference and exhibition in 2003, more than 11,000 attendees could visit a gallery of commercial and public sector booths devoted entirely to emergency response planning tools and solutions. An equally prominent theme was featured at the 2003 Autodesk University conference and exhibit, as well as many other surveying mapping and GIS conferences over recent years.

For many, the most visible of the RM Es tends to be the software solutions, which provide the actual maps. It is not to say that the development of such tools is easy (or inexpensive), but the design of such tools has been fundamentally at hand, by nature of existing GIS viewing and analysis applications. One can find customized solutions featured prominently on the websites for the commercial interests, as well as those of many public sector agencies. A fine example of these types of theme specific mapping tools is listing on the Crisis and Response Mapping Center for the State of Indiana (http://www.in.gov/ctasc/mapping/tools.html), and one only has to do a web search for "emergency mapping tools" to find any number of ambitious response planning portals. This is all good news; it is possible to provide instantaneous access to a wealth of existing infrastructure records, thematic GIS data, scanned maps and plans, to the emergency response personnel via Web-based, standalone and wireless solutions.

What one will find little of in such a web search is a decent treatise on the field collection component, or in-depth planning for a wide range of field contingencies. This is not to overlook the actual mapping steps, but it is hoped that years from now, when mapping software may be a standard toolbar on most desktops, the field equipment, trained personnel, equipment, communications, and backup contingencies are as well thought out. One can find situation specific examples for individual types of events; structural deflection monitoring, crash-site investigations, landslide analysis, search and rescue. There are fabulous tools available to fit almost any scenario and several valid methods for dealing with them.

Though impossible to think through every possible scenario, one interesting exercise is to reason through a few scenarios that come most readily to mind. Gather a few peers together for an informal brainstorming session, work through a few of the following event types, consider changing conditions during the site mapping process, and you may see some common patterns and procedures that may apply to many more event types.

You must also plan for a likely changing scenario, consider the probable and the improbable. In making assumptions as to which solutions may be practical in any given scenario, you might be surprised, then perhaps taken aback by the questions posed by emergency response folks who rightly tend to think through the worst possible cases.

Figures 1 and 2 illustrate an example of an exercise where post-event site conditions needed to be mapped on a tight time line, but where direct site access was limited. It was decided that RTK would be used for main features and site control, and remaining features would be mapped from a nearby vantage point using reflectorless total stations. A combination of actual and simulated conditions changed this scenario and plan of action.

Getting creative in the face of adversity is an invaluable trait. In The Right Stuff, author Tom Wolfe described the thought process of test pilots in crises of almost insurmountable odds: "I’ve tried A, I’ve tried B, now to try E". In the words of Epicurius "Skillful pilots gain their reputation from storms and tempests." We should not wait for a disaster to test these plans, nor should we completely withhold improvements and efficiencies only for emergency situations.

One proposal for testing field mapping skills and mobility of field crews, rather than a purely hypothetical or simulated event, is to try out some of the methods on ongoing lines of business. What project manager would object to a survey returned ahead of schedule? (with the understanding that this was accelerated as part of contingency training). Would it be an effective use of emergency training budget to allow crews on a current design/construction project to take a little more time to test out some backup methods?

Not too far in the future it may be possible, and is highly probable, that emergency response planners could take advantage of a system like the following. Minutes after an event, planners could log into a secure Web portal at any time, and from practically any location (via wireless) a preliminary site map is created using a deep pool of inter-local thematic data. On this Web-based map interface, the responder can request a site survey and highlight the extents and key features needed. A roster of on-call qualified personnel is notified, and guidelines are available that describe how to handle this type of scenario and what equipment is needed and available. Backup and standalone data and mapping tools are available. The site survey is completed, and the data is posted directly to the mapping application via wireless, or the next available method.

The pieces, for the most part, are already here. Now is time for the action planning.

Gavin Schrock is a surveyor and GIS Analyst for Seattle Public Utilities, where he focuses on using digital data to improve the cost ratios for engineering projects. He has worked in surveying, mapping, and GIS for 23 years in the civil, utility, and mapping disciplines. He has published in these fields and has taught surveying, GIS, and data management at local, state, national, and international conferences.

Among the scenario changes posed by the event coordinators were:
Q. What if your crew with the total station is unable to reach the site?
A. The GPS receiver and laser range-finder from a nearby facility could be used.

Q. What if the central server for your GPS network fails?
A. Data could be downloaded for post-processing via direct cell link to the base-station.

Q. What if your cellular communications fail? (which coincidentally did happen during this simulation)
A. One of the network base-stations is transmitting corrections via radio.

Q. What if access to the GPS satellite data is compromised? (However unlikely it is that all satellites would become unavailable at once, people cannot rely entirely on GPS for a number of reasons, primarily because a sky view is not always possible.)
A. Traditional trigonometric surveying methods may be employed, establishing locations by referencing know locations.

Q. What if there is no control nearby?
A. Many other options exist, though perhaps yielding less-than-accurate results: use known objects on the ortho-rectified aerial imagery and corresponding planar coordinates, astronomic observations, sight other landmarks, stadia and plane-table (which was previously often used for crash site mapping).

Q. If all technology tools were unavailable, how would you proceed?
A. Rest assured, if anyone can figure out the best way to provide field measurements, surveyors would certainly be the best qualified and most experienced at doing so.

Any time-sensitive or time-critical need for mapping or site evaluation services may be a candidate for the application of RME. These may include:
Natural Disaster Response
Site mapping to evaluate the spatial condition of a site or structure
Storm or damage/flooding
Settling, sinkholes

Non-natural Disasters
Human initiated unintentional or accidental:
Vehicle collision with infrastructure (e.g., bridges)
Utility breaks

Accident and Crime Scene Evaluation, Terrorist Event Scene Evaluation, Civil Engineering/Utilities Time-Sensitive Issues
Construction timelines
Critical redesign
Seasonal and operational time constraints

A 2.958Mb PDF of this article as it appeared in the magazine complete with images is available by clicking HERE

About the Author

Gavin Schrock, LS

Gavin Schrock is a surveyor and GIS Analyst for Seattle Public Utilities, where he focuses on using digital data to improve the cost ratios for engineering projects. He has worked in surveying, mapping, and GIS for 23 years in the civil, utility, and mapping disciplines. He has published in these fields and has taught surveying, GIS, and data management at local, state, national, and international conferences. Contact Gavin Article List Below