EWB-USA Technical Paper 101: Field Mapping ~ A How-To on Mapping in a Developing Country

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Field Mapping

A How-to on Mapping in a Developing Country

Christopher Kirkland1, Briana Herrmann2, and Jon Fripp PE3 Subject: Information Systems Key Words: Mapping, GPS, AutoCAD, Assessment

 

Abstract: A basic map of a community is essential for its residents to receive adequate services, such as water and electricity. When proper surveying techniques are not available, alternative methods can be used to complete a map of an unplanned community. This paper explains how sketching, photography, and GPS data were used to create a house-by-house map of an unmapped community in San Mateo, Belize. The final product was put into Google Earth and AutoCAD to provide interactive and static versions to allow for various uses. The goal of this paper is to provide guidance in properly gathering and evaluating data from a developing community that can be utilized to provide a map to fit the community’s needs.

Objectives

This report describes a mapping technique for developing communities used by the Engineers Without Borders-Texas A&M University chapter. This technique was developed during two assessment trips to San Mateo, Belize in 2012 and 2013. This report describes a first-pass surveying technique, intended to create a basic layout of a small town that can be used as a guide for further study. The mapping procedure includes sketching, collection of GPS data, photos, and the construction of electronic maps using AutoCAD and/or Google Earth. The authors believe that the techniques presented could be used and adapted by any development aid group. Also presented is a list of lessons learned to accelerate the learning curve for Engineers Without Borders chapters or other organizations attempting to map their own partner communities.

Research Background

San Mateo, Belize is an underdeveloped community located on the island of Ambergris Caye off the coast of mainland Belize. The 55 acre town is built primarily on reclaimed mangrove swamp using scrap wood. The majority of the area lacks solid dry ground; most homes are built on piers. Makeshift bridges created from wooden planks connect 1 Mechanical Engineering Student, Texas A&M‐EWB   2 Civil Engineering Student,  Texas A&M‐EWB  3 Civil Engineer Technical Mentor, Texas A&M‐EWB, North Texas Professional EWB, and Southern Methodist University‐EWB 

many of the homes in the back of the town. The unreliable access to homes has prevented utility companies from properly serving the area. In addition, the roads leading through the drier areas of the community are constructed from gravel piled on top of organic material (primarily trash) filled in with sand.

At the time of the assessment trips, the lack of basic services in much of the community was due to the aforementioned difficulty of access, as well as a serious lack of knowledge about the community layout. The nearby town of San Pedro had no direct jurisdiction over San Mateo, but did provide some basic services. This effort was hampered by the fact that the government was unaware of how many homes existed in San Mateo or even how many people resided there. At the time of the first assessment trip, very few (<5%) of the homes were older than 14 years. Over the course of two assessment trips, the EWB-TAMU team created and refined a process to locate individual homes, identify major roads and bridges, and provide a rough estimate of the population. The primary constraints were the small size of the team (8 people), the lack of expensive surveying equipment, and the relatively short time available for mapping (around 1 week for each trip, including other information gathering). This report will prepare future organizations for efficient field mapping with limited resources in a developing community.

Preparation

Data and Maps: The mapping team’s most important resource will be knowledge of the region. Before travel, the team should study any available aerial or satellite images of the target area. Become familiar with local landmarks, geography, and access points. Careful observation should be taken when viewing satellite images, as the images found may be several years old. Utilizing Google Earth imagery to visualize the changes in the region over the past several years can be beneficial in seeing any growth pattern or additional geographical features that have recently occurred.

Several base GPS points should be found using a satellite imagery program (Google Earth). These coordinates should be located on recognizable landmarks within the region and should be recorded for use in-country (i.e. Hotel, bank, etc.). These will serve as reference points to confirm the handheld GPS is functioning properly when in-country.

Team leaders should identify where the team will be staying and any good gathering points in case of emergencies. The distance finder feature on a satellite imagery program can calculate distances between locations, such as the distance between where the team will be staying and the closest hospital. Another use of this function is to determine how far the team will have to travel each day from their place of stay to the community center. This will give the team an approximate travel time in which they can plan the day’s events accordingly, provided they are staying outside of the community.

Each team member should know the following information, which can be obtained from a mapping service such as Google Earth or Google Maps:

Geographical features of the community Reference coordinates Location of residence while in-country Location of emergency meeting points Distance from place of residence while in-country to work site

Mapping Group Responsibilities: Mapping team members should be selected before traveling to allow for time to practice. The authors established that two mapping teams of three people worked best, but this might change for other organizations depending on the availability of team members and the complexity of the work required. The following describes the roles within each mapping team. These roles are what EWB-TAMU found worked the best in San Mateo. These may be modified to fit a specific project.

The first member of the mapping team is the photographer. This person is responsible for taking photos of the homes and tracking the GPS coordinates. Permission should be granted from the homeowner when taking photos of homes throughout the community. Collecting house photos is important for three reasons. First, many of the residents that EWB-TAMU encountered were not completely comfortable with overhead maps. Therefore, having photos of each house served as visual aids to families in order to identify their home location once the map is complete. Second, the photos can be incorporated in an electronic map on Google Earth (see Post-Assessment Procedure). This electronic map serves as an interactive visual aid to the community. Third, having photos allows the team to communicate certain characteristics of the community to other team members post-assessment.

The next member of the mapping team is the sketcher. This person will need to draw a rough layout of the roads and homes while the team moves throughout the community. Therefore, visualization of an overhead layout of the town and keeping a consistent grid and scale is crucial for this job. If possible though not required, the sketcher should be someone with good drawing skills or even artistic experience. The sketched map should include house locations and their corresponding assigned house numbers that will be determined by the scribe.

The final member of the mapping team is the scribe. This person determines and records the rating scale for each home; records the corresponding house number, photo number and rating; and records the GPS coordinates that is to be called out by the photographer. During the EWB-TAMU first assessment trip, the mapping team had the scribe rate the overall quality of construction of the homes using a predetermined scale. This scale was based on features like new paint, sand filled yards, or multistory structures. The intent of such a rating system would be to provide a simplistic view of economic divisions within the community, which might influence how projects are implemented. More information about these ratings is provided in the In-Field Procedure section. Regardless of whether the handheld GPS unit can store coordinates, recordings of the GPS coordinates should be written in the mapping journal as insurance. They should also record specific data that is relevant to the project (discussed further in the In-Field Procedure section). The scribe should be careful to

communicate with the sketcher whenever they assign a house number, so it can be added to the sketch accordingly.

Figure 1: In-Field Sketch of Community

Electronic Mapping Equipment: All equipment for the mapping team should be purchased well in advance in order to practice and identify potential problems that may arise with the equipment. The most important tool is the handheld GPS unit. Among other features, it should be rugged, water-resistant, easy to read in direct sunlight, and simple to use. Ideally, it will also be able to store dozens or hundreds of locations, as this will ease the electronic mapping process. Each member of the travel team should practice using the GPS to become familiar with the coordinate storage and retrieval process; extended use will also give an idea of the unit’s battery life. Make sure to bring extra batteries and a charging system. Each mapping team will need one GPS. GPS units are an excellent investment for a group interested in working in developing areas. If finances are an issue, the travel team may look into borrowing GPS units from other members within the organization.

It is highly recommended to bring a laptop and a couple of external storage devices (USB flash memory drives) with the travel team. A laptop will enable the team to begin

work while in-country. This will lessen the workload back home as well as bring attention to any mistakes or discrepancies in the data. Bringing portable storage with the team will serve as back up devices in case anything should happen to the laptop or written data. The authors recommend uploading any work onto at least two storage devices at the end of each day. Nothing can be predicted when in-country, so taking extra caution is always recommended.

Multiple cameras will also be necessary for the mapping team. They are subject to the same performance requirements as the GPS units, with the additional need for easy point-and-snap operation. Any relatively new camera should have acceptable clarity and resolution. Many cameras also have a video feature, which will allow team members to document the work they are doing. Taking videos of the community layout can benefit the team members who were not able to travel. Showing a video will allow team members to easily visualize the community and provide a better tool for discussion. Photographers should be familiar with the camera storage size and carry extra batteries and storage cards.

As an additional option, the travel team might want to consider the use of a laser range-finder. If the travel team has access to such an item, it might prove useful for locating regions that are visible but cannot be accessed by foot (houses across a river, etc.). However, accurately using such a device can be difficult depending on terrain and geographical obstructions. Unfortunately, EWB-TAMU was not able to successfully incorporate a laser range-finder into the mapping procedure, though such a device can be beneficial in adding accuracy to the mapping process.

Manual Mapping Equipment: Non-electronic items and knowledge will be crucial for the trip’s success. Blank, lined, and waterproof survey journals will allow scribe(s) to record data easily and safely. It may also be beneficial to print data sheets ahead of time to keep mapping information in a standard table format. Scribes and sketchers will need clipboards, preferably ones with storage compartments to house maps and recordings. Pencils and good erasers are a must for map modifications or data sheets corrections.

The travel team will also need several copies of overhead imagery maps printed on 8.5”x11”, 11”x17” and/or 24”x36”. The 24”x36” sheet usage will be described further in the End-of-Day Procedure section of this report. Team leaders should bring aerial maps that show the reference points selected earlier as well as their corresponding coordinates. The final pieces of equipment for the mapping teams are common-sense items: a first aid kit, snacks, water, sunscreen, bug repellent, and anything else that might be needed over the course of a long, work-filled day.

In-Field Procedure

Team Discussion: Proper communication with the team before setting out makes the day’s work more organized and efficient. Before heading into the field, the team should discuss the tasks and goals set forth for that day. Every member should be aware of their given responsibilities as well as the responsibilities of their fellow team members.

Everyone should have the proper equipment and be dressed accordingly. Communication devices may not be available for the project’s location. Therefore, meeting points at a specified time should be decided upon before the team separates. This allows the members to update the team throughout the day, ask questions that may have arisen while separated, and leave room for any adjustments that may need to be made within the groups. Supervision: The professional mentor or mentors on the trip should be closely involved with briefing mapping groups and if possible accompany them through the community. Mentors can provide valuable guidance when deciding on what features to include in the map, how to schedule and organize separate mapping groups, and how to adjust plans as new information becomes available. Scheduling meeting times for groups in advance will help the mentors keep track of students and monitor their progress. Scope the Area: The team should take a brief site assessment of the community on their first day in the community. Walking around together and becoming familiar with the community layout will help the team become comfortable with the environment and take note of anything that would hinder the team’s in-field work.

While taking a walk through of the community, the team, if applicable to the project, can establish a standard rating for the homes based on the conditions seen. A rating system should be determined based on the project goal. For instance, trying to find the source of a predetermined condition (poor water quality, sickness, etc.) may be knowledge that is desired for the project. Once this information is input into the map, the team can identify a correlation between their data and the differences in the community households.

If allowed, the team should ask any community leads or NGO’s present in the area if there is any map available already. For an example, a map was available in San Mateo that only a few people were aware of. It was originally developed for property line purposes. The map proved inaccurate to how the community was actually viewed, but allowed EWB-TAMU to develop an overview of what was to be expected.

Figure 2: Community Property Line Map

Establishing Map Characteristics: The survey team will need to identify which map characteristics they will want to note before entering the field. This data adds dimension to the finished map. Such characteristics can range from household amenities to health effects found throughout the community. The following provides an example of which map characteristics the authors used for the mapping of the San Mateo community:

Electricity (if visible) Water Lines (if visible) Septic Systems (vault toilets) Water purification system Roads/Bridges Landmarks (bodies of water, shops, etc.) Project-Specific Data (health-assessed homes)

A separate team of students with the EWB-TAMU travel team performed water and health tests at random homes throughout the community. By labeling which homes were visited and tested on the map, home locations could be correlated with the test results. This can be very beneficial to the project, especially when trying to reach the source of a particular problem within the community. It is important to note the caution that should be taken when releasing this map to individuals outside of the team’s organization. To avoid any arguments or tension amongst the community, it is advised not to share this map with individual community members. Blame could be passed from one community member to the next if a home is noted as having contamination or disease. When communicating sensitive results like these, it is best to collect the data

into a spreadsheet and strip out personal information. The information can also be discussed in private conversations with residents. Either approach will avoid alienating individuals while still educating community members.

GPS Reference Points: Ensuring that your GPS device is accurate and working properly is essential before beginning the mapping process. Correlate the coordinates the team established before leaving home with that of the GPS readings in-country. A good starting point is the team's accommodations while in the community. Keep in mind that the GPS readings will not be exact with the values found from a satellite imaging program (Google Earth), though they should not differ by more than a degree.

GPS Coordinates: The more coordinates the mapping teams can obtain, the higher the accuracy of the finished map. All roadway and landmark coordinates should be recorded. Begin by taking road GPS coordinates at all endpoint, intersections, and curvature points along the roadways. These points should be taken from the center of the road. The typical road width throughout the community should be included in the data recordings. All GPS coordinates taken should be recorded by the scribe and labeled by the sketcher on the sketched map.

At the team’s discretion, coordinates can be taken of homes. It is recommended to take a select amount of house coordinates and record their locations on the sketched map. These points will serve as additional reference points to check the finished map accuracy. It is recommended to record as many house coordinates as possible to improve the quality of the map.

Overlapping Yesterday’s Work: When surveying the community over multiple days, it is recommended to overlap the previous day’s work with the beginning of the present day’s work. Repeat the surveying process for a small portion of an area surveyed the previous day before continuing with the new day’s work. Tying in sections of the map will present flaws or errors to the team’s attention that can then be assessed and recollected if applicable.

End of Day Procedure: Set aside enough time within the team’s work day to complete the following end of day procedures:

Photo Tracking: Upload photos taken that day onto the laptop. Renumber the photos with the corresponding house number assigned. (For example, house number 26 may correspond with the photo number 180 on the camera. Therefore, renumber that photo number from 180 to 26). Save these to the laptop as well as to multiple external storage backup units.

Google Earth: If internet is available near the project site (internet café, bar, motel, etc), input GPS coordinates recorded that day into the Google Earth file. This can show the team if any incorrect GPS coordinates were obtained and allow the team to recollect this data on the next day. Further instructions for using Google Earth can be found in the Post-Assessment Procedure. Save this file to the computer as well as to multiple external storage backup units.

Transferring: This step is optional but recommended in order to lessen the work load once back home. Transfer data recorded by the scribe into an excel spreadsheet. Save to the laptop as well as to multiple external storage backup units.

Debrief the Team: Every member should describe their any challenges or interesting occurrences that happened that day to the team. This is an excellent way to brainstorm and discover new possibilities for the project. Allowing every team member to be updated on daily events gives everyone the opportunity to learn from mistakes or discoveries.

Post-Assessment Procedure

Excel: Now that the team is back home, they will need to input their data into an organized system. The Texas A&M travel team used Microsoft Excel to input the survey journal into an electronic form that could be shared with the rest of the team and members of the community. This spreadsheet should show house numbers, characteristics of the homes, photo numbers, photos, GPS coordinates, and any additional information the team may have recorded. If time permits, it is recommended to begin this step while in-country. The team can then finalize and clean up the spreadsheet when back home. An example of the Texas A&M excel spreadsheet can be found in Appendix A.

AutoCAD: A basic knowledge of AutoCAD is desired for this portion of the mapping project. Appendix A contains steps that the team should take when designing the community map in AutoCAD.

Google Earth: Google Earth is a powerful and free mapping tool that can help non-profits create high-impact and useful representations of communities. The program can be downloaded free at http://www.google.com/earth/index.html for Mac, PC, or Linux operating systems. Follow the steps in Appendix A to produce a map with controllable layers and photos of the area, available for use by anyone with Google Earth.

Image Hosting: If the team wishes to incorporate images into the Google Earth map, it is necessary to find a way to host the images so any map user can see them. Skydrive, Dropbox, Flickr, Photobucket, and many other services are available for hosting files in general or just images. Upload images to the team’s selected service and locate a sharing option. This should create a public html link, which allows any user to view a single photo. It is this link which should be copied into the “Image URL” box on each location marker. A marker with an attached image will have a distinct bouncing animation when the cursor is over it. Clicking on the marker will bring up a white box; after a long delay to communicate with the image hosting site, the image will appear. This method does require internet access, so users with no access will be able to view markers and layers but not images.

An alternative is to place every image in a larger folder along with all of the .kmz files (see Appendix A for explanation of .kmz files) and reference these images in the “Image

URL” section of the markers (for example, C:\Users\username\Documents\BelizeMap\ house_1.jpg). By sending the entire folder, the need for internet on the user’s end is removed. However, internet hosting has the advantage of allowing images to be swapped out in a single location to update the map for every user. In addition, the inclusion of every image file can make for a very large folder which may be too big for email. Finally, if the team has a website and can easily edit it, images can be stored on the website to both document the trip and host them for map access.

Lessons Learned

1) Bring multiple prints of the community layout. These should vary in size (letter, 11x17, 24x36). These layouts should be any aerial view of the community that can aid the team’s vision on the community’s topography (such as Google Earth).

2) Bring reliable clipboards that can withstand wind and rain. A portable storage clipboard would help protect your sketches and notes from any harmful weather.

3) A few proper working cameras are important when surveying. To make things easier, the team would want to try and use only 1 camera for the surveying process. This will make recording and uploading photos more efficient. However, extra caution in the team’s cameras should be taken when preparing for your trip. The team should be prepared with at least one of the following: 1 or more back-up cameras, extra batteries, and/or an appropriate camera charger.

4) Following the “End of Day Procedure” by uploading the team’s photos, GPS coordinates, and map transferring will be very beneficial to the team. Making sure your photos are labeled appropriately makes for a speedy process and less room for error. Inserting the GPS coordinates into Google Earth while in the community allows the team to see if any coordinates need to be reshot. Transferring the hand drawn sketches on to a larger print out (24x36) will show the team their progress and allow for any mistakes to be found and given the chance to be corrected. For an example, our team used two different cameras while in field and did not upload our photos until we were back home. Our numbering system ended up slightly skewed so we had to rely on memory to match some of the photos to their corresponding homes. By doing this process while still in the community, the houses and layout is still fresh in your mind and any discrepancies you may find could easily be solved the next day. Fortunately, our team did input the coordinates we recorded every night into Google Earth as well as redraw the map onto a larger print. We ended up finding a few that were skewed and were able to go back the next day to properly reshoot the points again. Our team split into two survey teams to better cover the community in time. Therefore, by transferring both sketches onto a larger print out in the evenings, we were able to determine any sections of the community that may have been neglected. Based on our team’s mistakes, it is highly recommended to follow the “End of Day Procedure” every night to ensure accuracy and fewer headaches.

5) By taking GPS coordinates of certain landmarks throughout the community of neighboring town can show a reference point for the person inputting the coordinates into Google Earth or AutoCAD.

6) As noted under the “In-Field Procedure” section, it is very important to determine a rigorous rating scale for the community as a team. Ensuring that everyone understands and agrees upon a set of detailed rating conditions will allow for consistent results.

7) It is easiest to split up the community, using an aerial or satellite photo, into sections to map that can be mapped within a few hours. Before beginning the mapping work for the day, the team should assign sections of the community to be mapped to each group. This will increase the team’s efficiency and organization.

8) While in field, we found that traveling light was the easiest way to perform our job and interact with the community. Bulky backpacks may not be very accommodating when entering into the community members homes. Carrying pencils and clipboards and cameras can be tiring and hinder the team's efficiency. We recommend wearing one of the following: a pocketed vest, fanny pack, or a small flat backpack.

9) There may be other tests or procedures that need to be followed out during the team’s time in the community but mapping should be considered first priority. Focusing on the mapping first will allow the team to stay together on the same task and allow for any mistakes to be found and fixed before leaving.

10) Keeping two records of the team’s survey data while in field is important in case of any weather damage or lose of the data sheets. Recording duplicate data sheets may seem tedious but acts as insurance to the team’s hard work while in field.

Conclusion

Conducting an assessment trip can be difficult even with excellent knowledge of the community. In an unplanned town, it can be nearly impossible to gather reliable data about the entire region. This makes a basic understanding of mapping techniques valuable for anyone interested in development aid. The authors’ experiences in San Mateo, Belize allowed them to develop a flexible, easy-to-learn mapping procedure that can be applied to any unplanned community of reasonable size.

The success of any trip depends heavily on preparation. Team members must understand their role in the mapping groups, whether they are the photographer, sketcher, or scribe. Delineating responsibilities clearly ensures that no information is lost due to carelessness. Teams will need to practice with each other and with equipment that has been purchased in advance. Electronic gear such as cameras and GPS units is important, but so too are the basics like journals and clipboards.

It is not enough to make excellent plans for a mapping project; plans must be followed while in the field. Understanding the information that the team needs is crucial, both to save time and to ensure completeness. Procedures like overlapping surveyed sections

and checking GPS data against reference points will catch errors the moment they are made. Consolidating work at the end of each day also serves to identify problems and to safeguard the team against loss of previously-collected data while in the field.

Mapping information can be collected into a professional-easy to use format that is static (AutoCAD) or interactive (Google Earth). AutoCAD has the advantage of creating easy-to-print maps and is a format often used by civil engineers, so it may be best for groups working with professional engineers. Google Earth provides the ability to move around on the map and even add pictures, and the software is free for anyone. This makes the maps excellent for identifying individual family homes or as a fundraising tool to “walk” donors through the community.

The authors and their team made a number of mistakes over the two trips as they developed the mapping procedure, which at times were extremely costly in terms of time and quality of results. These lessons learned include details about packing, procedures, and quality control of the final map. They may prove particularly useful for a group which has already practiced some kind of mapping but wishes to correct flaws in their process.

The authors hope that this report proves useful to many groups working on development aid projects. In the case of questions or comments about the report, readers may email vpprojects.ewbtamu@gmail.com. As always, development work is constantly changing, and suggested improvements are welcome.

Appendix A: Step-by-Step Instructions

AutoCAD:

1) Project Layers - Set up the layers in the CAD file to correspond to the maps features (water, GPS points, roadways, homes, etc.). Darker colors within AutoCAD print darker on paper, therefore keep in mind which features should be accentuated and which are not as important to the map. Utilize the line type features to define different map characteristics. Reference M1.3 – Health Assessment Map for a visual.

2) Title block - Create a title block for the project. This should include an organization logo, university logo, name of project, location of project, scale, date, team members, and AutoCAD designer. The title block is typically 24”x36” in size.

3) XREF’s – Overlay an aerial photo of the community. Find the distance of a particular feature on the aerial photo using the distance function in Google Earth. Use this dimension to scale the XREF’d image (aerial photo) to the equivalent size in the CAD file. This will be used as a guideline for the mapping process. Note: The location of this image in model space may need to be changed once the GPS coordinates are inputted. Reference M1.2 – Assessment Map with Aerial Photo for a visual.

4) Scale - Establish a scale size that will allow the map to fit within the 24”x36” title block. Use the XREF image to check the scale (Example: 1”=100’).

5) Add a north arrow and scale bar. If not found within AutoCAD symbols, these features can be downloaded for free from various AutoCAD forums online. EWB-TAMU used www.cadblocksfree.com.

6) Insert the road coordinates. There are many ways the team can accomplish inserting the GPS data. If the team is able to download the coordinates from the handheld GPS device, an option may be to import the coordinates. If this is not an applicable option, manually inputting the coordinates would be the alternative. EWB-TAMU utilized the manual data entry. This is how it may be accomplished:

a. Convert the GPS coordinates into UTM (Universal Transverse Mercator) coordinates. There are several website available to convert these. Keep in mind that there will be a large number of coordinates that will need to be converted. Therefore, choosing a website that can convert a file of coordinates (in excel) will be very handy. EWB-TAMU used the website www.earthpoint.us. Note: Conversion to UTM coordinates is not required but recommended as it simplifies the data entry in AutoCAD.

Figure A-1: GPS to UTM Coordinate Spreadsheet

b. Set up a new layer for the points and choose as the current layer. c. In the AutoCAD file, type “units” into the command line. Change the

“Insertion Scale” to meters (the UTM coordinates should be in meters) and the “Type” to decimal.

d. Establish an origin. Type “point” into the command line. Set the point to (0,0) to establish a false origin.

e. Insert the UTM coordinates by repeating the “point” command. The X value should be the Easting coordinate and the Y value should be the Northing coordinate.

7) Now that the road coordinates are inserted, the design the community roads may now be created by connecting the road coordinates with a polyline. If the coordinates were taken from the center of the road and the team recorded the road width, use the offset function to offset the road centerline to the edge of road. For instance, if the road is 24 feet wide, offset the centerline by 12 feet on each side. Note: using a polyline (command: PL) to draw the centerline of the straight sections of road will keep any curves in the road intact when offsetting.

8) Insert the remaining coordinates. These coordinates can be such things as houses, landmarks, waterways, etc.

9) Utilize the coordinates and sketched map that was developed in field to design the rest of the map (i.e. location of the homes and landmarks). If the sketched map is neat and precise, it may be scanned into an image and XREF’d into the AutoCAD design (much like Step 3). This image can then be underlain to the roadways that were previously inserted into the file. If the sketched map serves more as a visual, there is no need to XREF in the sketched map. Instead, the team may go off of the visual and memory to best approximate the houses and landmarks locations.

The houses and landmarks can be drawn in the CAD file at the team’s discretion. Using the coordinates of the landmarks and select homes will serve as the best

means to develop the map. These coordinates can be viewed as check points to ensure that the team is inserting unmarked homes correctly (homes without coordinates).

10) Label the houses to the appropriately assigned number. Each house should have a number that correlates to the data obtained in field and should be clearly labeled on the map. Reference M1.1 – Base Map for a visual.

11) Label any landmarks (restaurants, shops, schools, bodies of water, etc.) and street names.

12) If applicable to the project, create a symbol or marking to show where tests had been performed. This could range in a darker color for homes that had their water tested to labeling with an alphabetical code to be called out in the notes. Reference M1.3 – Health Assessment Map for a visual.

13) Establish a notes section of the map design. These notes should include: a. Any discrepancies within the map that should be brought to the reader’s

attention. b. Where the correlating data can be obtained. c. Reasons for the house numbering (as not to offend any of the community

members with why a house was labeled #110 and not #1). 14) Note: The polyline function in AutoCAD (command: PL) is a great tool especially

when creating the map. It connects the lines drawn in a group, allowing for easy edits and moving. A polyline can also be easily edited to better the appearance of the line, for such things as line type and line width (command: PEDIT).

Google Earth:

1. Sort GPS data into categories. Primary groups might include house locations and marker points along roads. Other groups include more specialized information like homes visited by a medical assessment team.

2. Create a folder for each group of GPS points by right-clicking “My Places” on the left side of the screen, and going to Add -> Folder. One of the folders should be labeled “Reference Points” or something similar.

3. Zoom into the region of interest by using the mouse to click and drag the scroll bar on the right side of the screen (plus and minus symbols).

4. Adjust the tilt of the view to vertical by clicking and holding on the downward arrow inside the inner circle of the compass at the top right of the screen.

5. Click on the reference point’s folder to select it. Then, click the yellow thumbtack image at the top of the screen to add a new point to this folder.

6. Enter a name for the point, which might be the point number, house number, name of the landmark, etc. Enter the GPS coordinates and include a picture link by clicking “Add Image…” and entering the URL into the box (see below for more details on image hosting). Adjust the icon and label’s size and color under the “Style, Color” tab, and select an informational marker, if desired, using the yellow thumbtack icon next to the point name.

7. Repeat Step 4 for each point in the reference points category (make sure to use GPS coordinates obtained on the ground, not from Google), then move on to a new category and repeat. Use different colors or different symbols to make layers stand apart.

8. Check to see if the reference points are lining up with the landmarks shown on the satellite image. If not, check to see if there is a consistent error in the points (i.e. all of the markers are shifted to the right of the landmark image). If this is the case, use the “Add Image Overlay” tool at the top of the screen to insert the satellite image used for the paper maps. Select “Browse” to find the image, and use the green corners to shift or scale the image and diamond to rotate. When the overlay landmarks match, hit “Ok” to insert the image. Make sure the image is inside the reference point’s folder in the left-hand navigation bar.

9. When the road points folder is complete (if applicable), connect the road points using the “Add Path” tool at the top of the screen. Open and click from road marker to road marker to create a path. Use sketches to help guide how the road is drawn. If different types of roads were observed and recorded, give the path a unique color. Hit “Ok” after putting in the path to confirm. The path tool can only handle single trails, therefore use the path tool multiple times if the road branches.

10. To make the map less cluttered, move the road paths items into a separate folder. Most viewers will not need to see the GPS points used to draw the roads.

11. Add an informational point into each folder with a label crediting the team and noting the timespan when the information was collected. If the map finds its way to other organizations or individuals, it is important that they know who to contact with questions.

12. Click the check boxes next to each folder to make the layer appear or become hidden. Turn off layers that cause excess clutter; a good starting set of layers would be roads and houses or even just roads.

13. Right-click on each folder and select “Save As” to save each map layer individually. The files will have a .kmz extension.

14. Send the .kmz files to anyone wishing to use the map. The files can be sent altogether, or can be sent individually (allowing only certain files to be provided). This is particularly important if some layers contain sensitive or private information like assessments of house condition or disease risk of residents.

Note: The following attachments are the resulting data and maps from EWB-TAMU Belize Project. They may serve as visuals for anyone who so desires to use them.