Base Map Techniques and Sources of Information

This piece was originally published in Giving the Land a Voice: Mapping Our Home Places, edited by Sheila Harrington, LTA Land Trust Alliance of British Columbia, copyright 1999.

Science is based on human values and is itself a Value System.” – Abraham Maslow, Motivation and Personality

Before launching into the details on what and how to map, there are several preliminary decisions you need to make to provide some focus. First, you should decide the purpose or objective of your map(s) which will dictate what you need to map, the size of the area you want to cover, the size of the finished map(s), and the level of detail you wish to include.

Some examples:

Habitat/Stewardship Potential

What are the main species; what are the habitat types found; their distribution/condition; and what needs to be maintained or enhanced to increase long-term viability.

Potential Resource Management

What is available for extraction or development (water, plants, trees etc); how is it distributed; what is its natural replacement (assuming it’s renewable) or enhancement potential; and what are the associated values.

Agriculture/Sustainable Development

What soil types and soil use history does the land contain; what are the conditions of sun/shadow and other weather factors such as wind/rain; and how can these be considered or enhanced for human sustainability.

Social/Community Values

What is of value on this land which can be maintained now and into the future: are there historic buildings, underground springs, aquifers, gravesites, or other human features of significance which may be of importance for the current landowners, future landowners, or the larger community.

Favourite or Cherished Places

What are your personal favourite places, views or quiet spots; if your map is to be passed on, these places may not be initially obvious to new landowners who are focused on their own visions of the land and their own needs/uses.

None of these examples are mutually exclusive, nor do they exhaust all the reasons for preparing a map. However, they do give an idea of the various reasons landholder or community mapping can be done and the direction or focus of your mapping plans.

After focusing on the purpose of your maps, you will also need to think about size. Determining the audience for the maps will help you decide on the size of the area you wish to map and the size of the finished maps. This chapter describes how to make a base map at a parcel level. See Chapter 6 for further base map techniques for larger, community or bioregional-scale methods.

Creating a Parcel-level Base Map

To create any form of map you will first need a base map onto which your selected information can be plotted. Any map will suffice as a base map, but good base maps are those that have a minimal amount of information on them so that you can place features in their actual geographical position. A map that shows only coastlines may not have enough geographical information on it to locate all land features. Conversely, a map that shows coastline topography, geology, and vegetation, may have too much information on it already to clearly locate additional features.

To be able to fit features onto a map clearly, particularly for parcel-level mapping, it is advisable to use a map that will show the parcel in a large scale (see Box 1).

Keeping these two points in mind, there are at least five ways to create a base map. They involve using the following methods: freehand or mental mapping, lot survey, aerial photos, copying from other maps, and creating an original survey.

About Scale (Box 1)

A map’s scale indicates the relative ratio between distance on the map and distance in reality. For example, a map with a 1:10,000 scale indicates that that one unit of measure­ment on the map (e.g. one centimetre) is equivalent to 10,000 units of measurement in reality. Scale is expressed three ways on a map:

  1. textually, e.g. one inch equals one mile.
  2. visually, with a bar scale, e.g.
  1. numerically, e.g. 1:5000.

A map with a large ratio such as 1:1000,000 is called a small scale map. A map with a small ratio, such as one inch equals a quarter mile, is a large scale map.

1. Freehand or Mental Map

Draw a freehand or mental map of the area from your mind’s eye. This may help you get started thinking about what you want to map and in relating it to paper.


  • any size sheet of blank paper
  • pencil
  • imagination and self-confidence in sketching


  • very easy
  • can create map of any desired size
  • makes map more personal
  • lends itself more to artistic maps


  • no true scale, so it may be hard to work with when geographical locations and distances are important


Visualize the main geographical features of the area (e.g. property boundaries, forest boundaries, streams, shoreline), and then draw them on paper.

2. Lot Survey

Visit a local surveyor, realtor or land title office to obtain a lot survey plan of the property.


  • none


  • very quick and easy to obtain


  • not very useful if your map boundaries are not property boundaries
  • may cost a small fee
  • a survey is not always available for the area you want to map


Find the legal description of the property, which is given on any legal land title papers.

Tools Needed (Box 2)

The following tools will be needed throughout the mapping process:

  1. sharp pencil – the best pencils are mechani­cal pencils which remain sharp and give a consistent line thickness
  2. velum – a type of tracing paper sold in sheets
  3. mylar – a plastic tracing paper superior to velum because it does not tear or shrink; however it is more expensive
  4. photocopier – required consistently in mapping
3. Aerial Photographs (Air Photos)

Trace geographical reference information from air photos of the area you wish to map.


  • 8×11 sheet of tracing paper
  • sharp pencil
  • air photo of area to be mapped
  • photocopier


  • very easy to do


  • if area is smaller than 25 hectares (50 acres) it will require considerable enlargement to get the map to a workable size.
  • air photos can be expensive and are not always available


In British Columbia air photos can be ordered from Maps B.C. (see Resources). In other areas, ask government agents if these photos are available.

University map libraries and government branches with libraries also have air photos, but these are not for loan. Once the photos have been obtained. simply mark on the air photo the perimeter of the area you want to map, or highlight any features such as rivers, roads or clearings that act as geographical locators and provide a basis for scale. Then, lay your tracing paper over the air photo and trace the desired information. If you wish to use this as your base map, use a photocopier to enlarge it to the scale you want.

Diagram 1: Aerial Photo
Diagram 2: Duck Creek Farms Map

Duck Creek Farm maps developed by John Wilcox using lot plans, survey maps, air photos and soils maps. (The original composite plan was prepared by Phillip Swift, B.C. Land Surveyor.) John drew in the creek and identified soil types by vegetation and by digging holes. He plans to take two acres out of the farm status he has for salmon enhancement and Fisheries, in addition to putting in buffer zones around all the creeks and ponds.

4. Photocopying from Other Maps

Photocopy or trace the desired area from a large scale map, e.g. cadastral maps (1:5000) or zoning maps (1:10,000), and enlarge them with a photocopier to the size you want the finished map to be.


  • cadastral, zoning or any other map that shows the area you want to map at a large convenient scale
  • tracing paper or velum sheets
  • sharp pencil
  • photocopier


  • very easy to do
  • scale readily known and easy to work with


  • scale may still be too small for some areas (less than 5 acres/2 hectares)
  • maps such as cadastral or zoning maps can be expensive to obtain.
Photocopying Maps (Box 3)

It is important to remember that whenever you alter the size of a map you are altering its scale. Thus a 1:10,000 map doubled in size will be a 1:5000 scale map. Most photocopiers indicate their enlargment or reduction size as a percentage. To calculate a new scale simply remember that scales are like fractions, i.e. 1:1000 can be written as 1/1000. Thus 1/ 1000 x 2 (100% enlargement) = 2/1000 = 1/ 5000.

Often maps will have both a numerical scale and a bar scale. When this is the case you can avoid doing the calculations by using the bar scale to measure distances, for this scale is always accurate when it has been enlarged or shrunk with the rest of the map.


Use a photocopier as described in the above method (see Box 3). Cadastral maps can be ordered from Maps B.C. Zoning maps can be purchased from your local municipality or regional district.

5. Survey Area and Draw an Original, Scaled Map


  • compass
  • tape measure or any device for measuring long distances
  • notepaper
  • sharp pencil
  • large sheet of graph paper
  • protractor (some compasses will work)
  • ruler


  • can produce map of most areas at any scale
  • more personal than traced maps
  • most satisfying map to produce


  • relatively difficult and time consuming
  • greater chance of errors to arise


First, select a fixed starting point, such as a property boundary corner post. Standing as near to it as possible, point the compass at the next corner post in a clockwise or anti-clockwise direction. Read the compass bearing and record it in your notebook.

Then measure the distance between the two points with a tape measure, hip chain or by pacing. If you cannot see the next corner post, aim the compass at a feature that lies in the same general direction, e.g. a tree. Repeat this process as many times as necessary until the next corner post is visible. It is essential that you note all bearings and distances clearly. The best way is as follows:

a) Use capital letters alone to indicate corner posts (called stations), and use capital letter plus prime number to indicate recordings between corner posts (e.g. C3).
b) Use 360 degree bearings when surveying, as it is less confusing when you transfer them onto paper.

Diagram 3: Plotting Your Survey
Diagram 4: Base Map

Sample Survey Notes: (Refer to Diagram 3 to see how this is plotted)

This process is continued until you end up back at the starting point. Make sure you remain consistent in your direction of travel, i.e. once you’ve started surveying in a clockwise direction, stay with that direction until you finish.

To double check your readings, take back shots of the previous stations as you move to the next station. This bearing should be exactly 180 degrees from the front shot.

If linear geographical features are to be mapped (e.g. river courses) use the same method as above. Start at the point where the river meets the border of the area to be mapped. Point the compass parallel with the stream course and measure the distance to the next change in direction of the stream course.

Continue this process until you reach the point where the stream passes out of the map area. Unless the finished map will be very large, it is not necessary to measure every meander of the stream, only the major ones.

Once the entire area has been surveyed, the data can then be plotted onto your map. Using a large sheet of graph paper, designate the top of the paper as 0 or 360 degrees (this will be equivalent to magnetic north). Starting at the first station in your field notes, plot the recorded data, using a protractor to measure the angles/bearings and a ruler to measure the distances. The ratio you use to convert distances in your notes to distances on your map will be the scale of your map. Once this data has been plotted, you will have something similar to Illustration 3.

Often when mapping polygonal features (e.g. property boundaries) you will find that the last bearing back to the starting point does not meet exactly. This is due to the cumulation of many small errors in measuring bearings and distance. There are many complicated formulas for correcting this, but if the error is not significant and the map’s purpose is not for exact navigation, it is easiest to “fudge” the last line and to join it to the starting point.

Next, lay a blank sheet of paper, velum or mylar over the rough map. With a pencil, mark the stations you require, such as parcel corner posts. When this is done, draw lines to connect these points. As Illus­tration 4 shows, you should end up with a clean, uncluttered base map. After copying the original, you will have a working base map upon which you can add other features you select.

Sources of Information

Once you have your base map, the next stage is to find and select information to add to it. Just about anything with a spatial element can be mapped: from the sites where your dog buries its bone, to where your various soil zones are located. For some people this is an exciting concept which causes them to overindulge in mapping features. This can be disastrous for a map as it will make it too busy for the viewer to absorb. (You can choose to layer information onto a series of maps thematically if there is a large variety of features you wish to include. See Chapter 6: Creating a Bioregional Map Atlas for details.) As long as you remember your map’s purpose, you will save time identifying what information you wish to find, ensuring that the map is meaningful to the viewer.

When researching information there are four general routes you can follow. They are:

1. Identification of Physical Features on Site (Field Survey/Inventory)

If you wish to map current physical features, there is no source better than your own observations, notes and resultant data. See the next chapter for detailed techniques on the field survey. You may also wish to check for existing surveys and inventories made by other people in your area. Check with local societies, businesses and government offices.

2. Data from Other Maps and Records

This is the next best source of information after physical identification. Federal government agencies keep records on salmonids and marine species, climate, stream flow, census information, wildlife, voting patterns, and a host of related data. At the provincial level, regional offices of the Ministries of Forests, Environment, Lands and Parks, Mines and Petroleum Resources, and the Land Title Office hold detailed maps of forest cover, resource extraction histories, fish and wildlife habitat and land maps which relate to their jurisdictions. Many First Nations have spent millions of dollars in the last decade promoting their interests with maps. Crown Corporations such as B.C. Hydro do mapping which will also be of use, as do private corporations who make maps for the promotion of specific economic development projects.

When looking for suitable maps there are at least five places you can go. They are:

I. Local Nature or Historical Societies

Local nature and historical societies are excellent sources of information and are probably among the first places you should go when doing research. You can meet people who have knowledge and interest in the local physical or historical features as well as knowledge of the sources of information on these features.

Local societies can provide such items as bird counts, sensitive areas surveys, archaeological inventories, historic/heritage resource inventories and biological surveys.

II. Archives

If any historical data is to be mapped, e.g. heritage home sites, old logging sites, etc., local archives are excellent sources of information. They store older maps and air photos which provide historical data which can be mapped.

III. Libraries

Like archives, libraries also provide historical information. In addition to maps, they hold books and articles on local history, studies and government statistics (e.g. annual precipitation, population, temperature etc.).

IV. University Map Libraries

Map libraries at universities are treasure houses of a wide variety of maps. At the University of British Columbia there is a central map library, plus specialized map collections held in the Departments of Geography and Geology. Not only can you collect a vast amount of information from these maps, it is a good place to look at different styles of maps, including labels and symbols you might use.

Most often, map libraries will not lend out maps, so you will need to take notes and photocopy the maps you most want to use, and then purchase them through other locations. Map librarians are on hand to assist in locating whatever category or scale of maps you are looking for. Unfortunately, due to the sheer profusion of maps being produced, University map libraries usually don’t hold the most current of maps.

V. Government Map Agents/Departments/Maps B.C.

In B.C. all government maps are put out by Maps B.C. In other areas, check with your local government agent. Besides cadastral and air photos, another useful map series sold by Maps B.C. are T.R.I.M. (Terrain Resource Information Management) maps. These show contours, roads, houses, lakes, streams and forest cover at a 1:20,000 scale. They are useful for base maps; however you need to order ahead. (Maps B.C. produce a catalogue which lists everything they sell.) T.R.I.M. maps, like most new maps today, are stored as digital data. If you have the right computer software, you can purchase T.R.I.M. maps in digital form. Otherwise, hard copies must be ordered and specially printed for you, which takes at least two weeks.

Because other maps will rarely be at the same scale as your base map, remember you can use a photocopier to enlarge or reduce them. If this isn’t possible, you can measure the geographical position of a feature using a ruler and then transcribe this onto the base map. To do this you must know the scale of both maps and have a common georeference point from which to measure (e.g. a road, that appears on both maps).

3. Air Photos

In addition to existing maps, air photos have been taken over all of British Columbia. They are useful sources of information if you are mapping large areas. To use air photos to their full potential, you will need two photos of the same area and a stereoscope. This is a viewing device which focuses on and magnifies the images of the photographs. By carefully manoeuvring the photos so that you get exactly the same image from each photograph (shut one eye and look through one lens; shut the other eye and look through the other lens) the result will be a 3-D effect called parallax. When you achieve parallax, tall trees, rises and falls in topography, buildings, etc. all become apparent. Because some level of expertise is required to calculate heights and identify vegetation in air photos, they are not as useful as field surveys/inventories when collecting data for parcel-level maps. However, they can be incredibly useful if you can obtain one from the 1970s, ’60s or even ’50s, because historical features such as old stream courses, homesteads, barns, forest, farmland, which no longer exist will be visible and, therefore, mappable. The most recent air photos can be ordered from Maps B.C. Older air photos may be viewed at map libraries, archives or planning offices.

4. Neighbours

Often the best sources of information for bioregional and historical or cultural features is one’s own neighbours, especially if they are long-time residents of the area. Information on features such as seasonal creeks, homestead sites, wildlife sightings etc. can all be obtained from the people who live in the area. Depending on the purpose of your maps, it also would be useful to call people who have moved away or visit an old-time resident of the region.

How to Transfer Data Onto Your Base Map

Once you have collected all the information to be mapped, you are then ready to notate it onto the base map. Transferring data onto a map is an art, because it must be done in a way that will be both clear and meaningful to the viewers. The two main techniques used for illustrating data are symbols and labels. See Chapter 6 for some additional tips and techniques for making a series of maps.

The best map composition involves a cohesive and critical view of the data to be mapped as well as a clear choice of symbols and text. Some real-world features, such as species counts and average or seasonal temperatures, are abstract concepts which do not relate to specific physical locations. These subjects may require unique symbols and effective words which will allow the map reader to discover interrelationships and knowledge about their home places.

Diagram 5
Diagram 6: Frog Map

The most common way to represent data on a map is with symbols (e.g. [] = house, O = old growth tree). When choosing symbols it is important to remind yourself of the map’s purpose. If the map is intended to be an artistic work, then you can be more creative and less systematic with the symboling (i.e. each symbol can be unique). If, however, the map is intended to be an information tool, symbols must be consistent, e.g., all trees = x. Some data, such as elevation, precipitation, forest land or open land can be illustrated using colour coding or lines indicating boundaries.

Before choosing symbols for a map, look at a selection of professionally produced maps to see different examples. The best widely available book of symbols that can be copied is Sourcebook to International Symbols (1972) by Henry Dreyfuss.

No matter what type of symbol you use, it is vital that your map have a legend that explains what they mean. It is also important to give your map a title, a north arrow, a scale, information sources, and last but not least, a date. These should always be located on the map where they are easy to see but do not interfere with or detract from the map’s visual image.


Usually in mapping it is necessary to label certain features that are unique and do not fit into a symboling system. Names of features such as mountains, rivers, streets, bays, etc. all need to be written on the map as they give the viewer some points of reference. If the map is intended for per­sonal or artistic use, then the labelling can be done by hand in any calligraphic style. If it is intended to be an information tool for others, it should be done carefully by hand or you can use Letraset or typesetting methods. In either case there are some techniques that you should always use:

With a sharp pencil and a straight edge, lightly draw a line where the label is to go. The label should be exactly parallel with the bottom of the map and with all other labels. Often this isn’t possible due to space constraints, but it is worth trying. People quickly give up reading maps if they must rotate the map through 360° to read all the labels. With linear features such as rivers and streets, it is acceptable to label parallel to their direction.

The most important aspect of making a good map is to keep it clear, simple and easily readable.

Diagram 6 illustrates how information can be shown with the use of symbols. It also shows how labelling is generally done. Note how all place names are parallel with the bottom of the map and with each other. This also applies to the map title and anything written in the legend. Bordering around the map and between map and legend is done to distinguish and highlight the main feature on the paper, the map! Maps should never go to the edge of the paper as, over time, paper edges wear off, rip, etc. Note also that scale and outside sources of information are clearly shown on the map, but do not detract from or interfere with it.

Creating a Finished Map

At this point you will probably have your base map covered in symbols and labels due to errors and accidents, a lot of eraser marks, wobbly lines, coffee stains, etc. If this is the case, you will want to create a finished map which is tidy and more presentable. Suggested methods follow:

  1. Lay a blank piece of paper, velum, or mylar over the rough copy map. You can do this on a flat table, on a window, or through the use of a light table. Align the bottom map under the upper sheet so that the bottom map appears centrally (or wherever looks best) within the border. After securing the two papers with removable tape, draw lightly with a sharp pencil the outer border of the map. Once this has been done, trace over feature symbols and labels that are desired on the good copy map.
  2. When all features and labels are on the good copy of your map, you can then “ink” them in with a pen. This means going over all your pencil lines, dots, etc. with a black or coloured pen (or use a series of pens with different thicknesses relative to what you want to stand out.) The type of pen depends on the quality of the map you want at the end. The map in Diagram 4 was inked in with a regular ball point pen. As you can see, this works, but it does not look like a profes­sional map. The frog map was inked in using three different types of drafting pens. (Drafting pen kits and rulers can be purchased at drafting supply stores or university book and stationery stores.)
  3. When the good copy map is finished, the last step is to photocopy the good map, enlarging or reducing it as desired. Note, however, if the map is enlarged or reduced, the map’s scale must be a bar scale. Since the bar is altered with the map, it will remain accu­rate. Other scales will need to be calculated. It is not essential to photocopy your map, but it is desirable since it leaves you with a “master” copy that can be stored safely. The “working” copy can then be used, modified or pinned on a wall.
Liked it? Take a second to support Quinn Collard on Patreon!
Become a patron at Patreon!