The surveyor’s role when natural disaster strikes

September 5, 2018  - By

No, this is not a drill or a major motion picture event.

During my lifetime, many natural disasters that have taken place around the globe. These unfortunate events have created mass destruction and caused many deaths by a variety of environmental elements, ranging from earthquakes and volcanic eruptions to hurricanes and snowstorms.

Disasters in the United States. (Image: FEMA)

Disasters in the United States. (Image: FEMA)

Once Mother Nature decides to unleash her wrath, rarely anything stands in her way. Some types of disasters create situations worse than others, but all have a reputation of leaving a trail of death and destruction.

Search and rescue is the first and foremost priority when it comes to these disasters, with cleanup and rebuilding to soon follow.

The role of the land surveyor, however, doesn’t usually enter the discussion when it comes to these situations. It has always been considered an occupation that fills an important role in development, construction and parcel ownership, but rarely is discussed in the same terms as a fireman, policeman or doctor.

We will take a closer examination at how the surveyor uses skills developed through education, technical training and practical application of geographical data to quietly assist those in need through these difficult bouts with Mother Nature.

First, however, we will discuss various types of the deadliest natural disasters, the amount of destruction that has been caused and types of problems (besides deaths) that were left because of these tragedies.

Disasters throughout history

When describing natural disasters, the obvious ones come to mind: earthquake, hurricane/typhoon/cyclone, tornado, wildfire, flooding/monsoon, drought/famine, volcanic eruption, tsunami, sandstorm, avalanche, and snowstorm.

All of these have wreaked havoc on mankind for centuries, with more physical destruction taking place in the past few centuries.

Some of the factors leading to an increase in this devastation are gains overall population and amount of buildings and improvements in populated areas. Let’s look at how each disaster impacts the areas in which it occurs:


Historically the deadliest type of natural disaster, rainfall through storms and monsoons cause flood events that have caused millions of deaths in several instances around the world. Most of the deaths caused by flooding situations are due to drowning in floodwaters that inundate areas not normally affected by normal amounts of rain.

The largest flood in recorded history took place in China during 1931, combining melting snow and ice with ongoing rain events to create a continuous flooding event that lasted most of the year. Death toll estimates range from 400,000 to almost 4 million, as many of the victims either died or moved to other regions with no trace.


This is another type of flooding disaster, but it combines large amounts of rain gathered from ocean storms with high winds to batter shoreline and inland areas. These storms can often stall in place, causing significant damage by both wind and rain.


Most weather systems associated with creating tornadoes are believed to occur in the United States, but they happen all over the world. Many of the deadliest tornadoes have taken place in the Middle East, including Bangladesh, Russia and Pakistan. These storms can include torrential rain, but most of the damage caused by tornadoes is wind-related.


Shifting tectonic plates and earth-shaking tremors are a significant cause of damage and deaths throughout the world. Most of the highest death tolls have taken place in Asia, with the biggest loss of life occurring in Shaanxi, China, on Jan. 23, 1556, with more than 830,000 deaths.

Indian Ocean (Jan. 2, 2005): A village near the coast of Sumatra lays in ruin after the Tsunami that struck South East Asia. (Photo: U.S. Navy/Photographer's Mate 2nd Class Philip A. McDaniel)

Indian Ocean (Jan. 2, 2005): A village near the coast of Sumatra lays in ruin after the Tsunami that struck South East Asia. (Photo: U.S. Navy/Photographer’s Mate 2nd Class Philip A. McDaniel)


Often a secondary disaster generally associated with earthquakes in coastal areas, tsunamis kill thousands by inundating shorelines with huge waves and sending vast amounts of water into low-lying areas and poorly constructed seaside villages. The largest tsunami in recent memory was on Dec. 26, 2004, in the Indian Ocean off the coast of Indonesia, with the death toll reaching 280,000 people.


The biggest cause of earthquakes is typically molten lava expanding to shift tectonic plates, but volcanoes are formed with the lava and associated gases finding an escape in the Earth’s crust.

Once a volcano has formed, an eruption can lead to significant damage from lava flow onto adjacent land and hot ash spewed into the atmosphere. Many volcanic eruptions throughout history have buried local cities and villages, making them virtually disappear.


Grabbing the headlines more recently has been the proliferation of wildfires. While not causing the substantial loss-of-life associated with many other natural disasters, wildfires are responsible for scorching hundreds of thousands of acres of forest and brush areas, as well as decimating neighborhoods.


This disaster only takes place in locations with significant snow pack and elevation changes. After large amounts of snowfall, various factors lead to movement of large areas of snow and ice down mountainous slopes. Often these events take place near cities and villages in mountainous regions and can leave the inhabitants buried and unreachable.

Other Types of Natural Disasters

While the varieties of events listed above can create large-scale destruction, there are others that, while smaller in nature, can collectively cause great damage and loss of life. Thunderstorms, snowstorms and sandstorms are wind-related and can be devastating to the areas being affected.

Other natural disasters that often don’t get the same recognition as those listed above include drought and famine. These environmental tragedies ruin thousands of lives, and it take years to recover from the damage caused by these inflictions.

Disaster hits. Now what?

June 28, 2008: A house in Parkersburg, Iowa, is being rebuilt while debris from a deadly EF5 tornado still covers the ground. (Photo: FEMA/Richard O’Reilly)

June 28, 2008: A house in Parkersburg, Iowa, is being rebuilt while debris from a deadly EF5 tornado still covers the ground. (Photo: FEMA/Richard O’Reilly)

All of these disaster types have led to a great number of fatalities and total devastation of cities and roadways. To help us understand what type of assistance the surveyor can provide, we first need to identify the conditions left by each of these events.

Most of the disasters simply wipe out whatever is in its path; from tornadoes, hurricanes, and wildfires to earthquakes, avalanches and tsunamis, the regions affected are left in shambles after the occurrence.

The initial search and rescue through the rubble takes manpower and careful identification of areas where people are known to inhabit, either as residences, places of employment or public spaces. These areas require retracement of existing mapping and atlases to accurately identify those places for timely recovery.

Once the search-and-rescue efforts have ceased and cleanup/rebuilding commences, the destroyed areas will need to be remapped based upon existing parcels and ownership rights. Reconciliation of existing parcels, subdivisions and rights-of-way will be required to properly return the injured areas to a habitable state.

The one disaster that’s a big wildcard, however, is the earthquake. The devastation is like the others and generally will need rebuilding like the others, but with one large difference; putting everything back where it belongs.

When large tremors cause significant shifts in inhabited and/or complex parcels, the ability to retrace existing parcels, subdivisions and rights-of-way to place them in their original location becomes a nightmare.

How surveyors and GNSS help before and after disasters

As expert measurers and establishers of boundaries, the surveyor provides guidance for the creation of parcels and rights-of-way. Through extensive education, training and experience, the surveyor combines field reconnaissance, legal definitions of parcels and high-level mathematics to provide direction for the creation and retracement of real property.

After experiencing a devastating event like the ones described above, the surveyor becomes a key position in rebuilding the affected area.

Prior to the invention and proliferation of GNSS technology, however, the use of state plane coordinate data was a tedious and time-consuming task (see my January 2017 article at GPS World).

Establishing coordinate values across a large region and/or utility system was not practical from a time or cost viewpoint. The arrival of GNSS technology in the 1990s changed that situation with the ability to determine coordinate values in real-time and create large databases of infrastructure and utility information. Government agencies (and surveyors) now could replicate, with acceptable accuracy and precision, locations of improvements and utilities throughout their jurisdiction.

2015 Fairdale, Illinois, tornado recovery. (Photo: NIU Today)

2015 Fairdale, Illinois, tornado recovery. (Photo: NIU Today)

Surveyors are now being called upon to assist with search and rescue efforts when these disasters hit to help locate and turn off existing utilities (i.e. electricity, gas, water), and to provide mapping assistance for retracing where people may be in the rubble. Because lives are at stake, timely location is essential for these services and GNSS technology use by the surveyor provides a much-needed service.

Once these disaster events being a rebuilding mode, the surveyor steps in to find the existing parcel and right-of-way lines to assist the respective owners where a deed or roadway was previously located. Most times, the surveyor can retrace existing line by locating buried monuments and recreating existing deed descriptions and/or roadway locations.

Where there becomes a problem is when the devastation is large enough to destroy all existing monuments and leave no trace of any occupied land. The surveyor must expand the search area, as far as needed, to find the closest available monuments in which to begin rebuilding the parcel descriptions.

Depending on the site conditions, GNSS equipment is used to locate the positions of the nearest monuments so the surveyor can perform retracement calculations for the disturbed area.

Once the area to be re-established to calculated, the surveyor can return to the site and place markers signifying parcels and rights-of-way for the rebuilding of roads, utilities and buildings. GNSS receivers are again utilized to increase the proficiency of the field crew by allowing the installation of the markers over a large area in a short amount of time.

How surveyors can prepare for future events

Image: DuPage County, Illinois, GIS

Image: DuPage County, Illinois, GIS

As previously written in my January 2017 column, GNSS technology has helped expand geographic information systems (GIS) into a database beast, containing everything from voter districts, zoning regions and floodplain maps to locations of most municipal utility maps and databases.

When these databases have included a geodetic layer of survey information overseen by the licensed land surveyor, the GIS is now more than a glorified digital Etch-A-Sketch. These entities within the database have geolocation as part of its dataset, with varying accuracy depending on the source of the data.

By having all this information available in a digital format, typically saved in a cloud-computing location, the ability to replicate these entities becomes a simple exercise. As more information becomes available, it needs to be included into the database for future mapping consideration.

All relevant data, together with a geolocation tag, becomes valuable for future retracement. This information could be used to locate possible survivors during a disaster event.

Upcoming technology to assist surveyors with disaster relief planning

Image: Esri

Image: Esri

Many of the tools being utilized by surveyors have the capability of helping with mapping and data collection of municipal and public facilities for GIS database inclusion.

We currently use laser and lidar scanners both terrestrially and aerially to collect point-cloud data for establishing existing conditions of various sites. This point cloud, along with high-resolution photography, can be used to augment and enhance new and existing GIS databases with extensive datasets.

By having this additional information collected and available digitally, qualified experts can perform disaster simulation tests to depict various environmental events and determine what strategies will be necessary for search-and-rescue efforts.

These experts can also use this data to predict potential flood paths, conduct seismic modeling to determine building shift, and combine weather conditions with conceivable wildfire-capable areas. All these potential life-saving exercises can utilize the surveyor as a significant data-collection source.

Coming to a theater near you…

Whether one believes in climate change or just being affected by an active environmental cycle of natural disasters, the entire world is prone to have an occurrence of at least one of these events.

Since these events are not going away, remember to help your fellow man, woman or child in their time of need. It is the duty of the surveyor to provide a service that is intended to protect the public, and being there for disaster planning, prevention and recovery is part of our mission.

Think of us like the Avengers; now there’s a sequel I’d pay to see.

About the Author: Tim Burch

Tim Burch, GPS World’s co-contributing editor for survey, is executive director of the National Society of Professional Surveyors (NSPS) and director of Surveying at SPACECO Inc. in Rosemont, Illinois. He has been working as a professional land surveyor since 1985.