A deep understanding of the sites soil conditions informs our design and install decisions around water, access, building, planting and so much more. Even before getting onsite to perform soil nutrient tests, excavation pits and perc tests, we can get a sense from our office chairs for the general geological conditions we may encounter in the field. The Web Soil Survey from the USGS is a fast, easy tool to understand the likely soil characteristics on our projects.
Using the Soil Data Explorer we have free access to data such as vegetation type, soil structure, water holding capacity and soil organic matter; you can really go down the rabbit hole of data. Here are some general instructions on how to use the tool.
https://websoilsurvey.sc.egov.usda.gov/App/GettingStarted.htm Try it out on your next project!
The above screenshot shows a 3D terrain model base from one of our topographic base maps. The team at Lars Langberg Architects used their magic to create the model which allowed them to put the building design into a spacial context
Below, you can see the map we provided that they used to create the model. Although all their secrets have not been fully revealed on the exact procedure to convert contour lines into 3D models, we assure you that it can be done.
Any 3D modeling program has the ability to do this. Sketchup and revit are some of the more common ones used.
As the model develops, we hope to provide a few more screenshots so you can start to see more ways that our maps can be integrated into 3D modeling. For example, we provide tree locations and diameters, and they will be adding in trees and vegetation for more accurate visualizations.
The world of maps is both mysterious and fascinating. It can inspire a great sense of curiosity and wonder for some, and a deep sense of confusion and dread for others.
Either way, I'm here to help demystify the mapping process for those who are confused and educate those who are interested. In this article I will break down the exact steps we take to produce high quality landscape base maps in a step-by-step easy to understand way. I hope you enjoy reading, and I hope you can walk away from this article with a little more understanding of what a base map is, how it's made, and how it is used in the design industry.
The Mapping Process
Ok, let's get serious. This is where I will explain to you the process we actually use to make the maps, from point a to z. Now that you understand what a total station is, I will start by explaining the process of how it works. See how-it-works-in-4-simple-steps.html for a more simple breakdown.
First of all, it is very important to set up the machine to be exactly level. Luckily we have a very nice digital theodolite that gets sent in for maintenance regularly and has a built-in leveling function. Once it is set up, calibrated, level, and lined up directly over the point we set in the ground, we begin by what is called "backsighting." This is what gives the machine a reference point in space to compare all of our other measurements.
Imagine for a minute you are mapping the above property that has a big front yard with a lawn, some planting areas, a house, and field off to the side.
In the yard we would place a nail into the ground (represented by the lower red dot) to mark an exact point on the property, and then place a second nail in the field to the side (the upper red dot) to mark another exact point. The yellow line going in between the two points now becomes the arbitrary reference angle (or "azimuth") that all other measurements will refer to.
In the backsighting process, we set the machine up directly over the first point and make sure it is level and in the exact correct location. Then we use the controller to tell the machine to lock it's laser beam onto the reflective prism that is on top of a staff we hold, and go stand at the second point with the prism (the prism reflects back the laser to machine, and the machine tracks the prism) Once locked on, we hold the staff steady directly on the second point and have the machine measure the exact distance and relative angle of the point we are backsighting. This measurement is then stored, and gives the machine a reference angle to work from. As the machine rotates and follows the prism around as we walk from point to point, it digitally keeps track of the angle changes in reference to our newly set azimuth. For each new point we hold the prism steady, and use the controller mark each point in the computer.
For example we would walk over to the corner of the house above, the machine would track our prism, and we would command the machine from our wireless controller to shoot a laser beam. The machine will then reflect the laser off of the prism, measuring an exact distance and recording it's angle of rotation from the backsight point we had previously shot. The recorded point then goes into the handheld computer device, and the mapping process begins point by point by point until we have something that looks like the screen shot captured in the picture below.
Collecting Coordinate Points
Foresite Mapping Llc is not a licensed surveyor, so we do no geo-reference our maps. All coordinates and elevations that we provide are therefor relative only to other elements shown within the mapping area and do not indicate any legal property boundaries.
A Licensed surveyor, however, will use either a GPS unit, or will locate points called benchmarks which give reference to the rest of the world using latitude, longitude, and elevation coordinates that have been placed within a datum. I'm not going to go too much into detail about what is a datum, but basically it is a system for approximating the curvature of the planet and projecting curvature onto a flat surface.
Like all other points we make in a map, the elevation coordinates we use to create contour lines are relative to the base point we created in the beginning to backsight our machine. Therefor if you wanted to have the elevation be represented in height above sea level, you would need to backsight to a point with a known correct elevation, latitudinal, and longitudinal coordinates. Likewise, if you want your map to be correctly placed within a global coordinate system, you would need to backsight to a point that geographically referenced, such as a bench mark.
When a lisenced surveyor backsights to one of these points, this is called geo-referencing, and it places the map in the right place relative to the rest of the world. This is especially important for establishing legal boundaries, and building roads or other projects that stretch over very long distances. At Foresite, we don't find that it is necessary for most design purposes to geo-reference.
If you want to measure an object that does not have a 90 degree angle, such as a tree or a point along a winding pathway, a process called triangulation will be required. Triangulation means measuring 2-3 other known points and using these measurements to deduce the location of a single unknown point.
Lets say that you are trying to locate the trunk of a small tree, and you just don't have the sight line from your machine, so you will have to triangulate using a tape measure.
In the diagram above, the orange lines represent your measurements taken with a tape measure, and where they meet is at the center of the tree trunk. From the tree to the corner of the workshop building is let's say 31. 48 feet, and from the corner of the house it is 15.25 feet. Because you already have recorded the corners of these structures, you can deduce the location of the third point from these 2 distance measurements. The pink circles in the diagram coming from the corners (this is a quick sketch, so forgive that the circle is not exactly centered on the corners) can be drawn on the map with the exact radius of the measurements taken. So the larger circle from the workshop corner is 31.48 feet, and the smaller circle is your measurement of 15.25. Where the circles intersect, you have your triangulated point. There are only 2 intersections, and therefor there are 2 possiblities of where the point is, however, you will take note of the approximate location of the object and will be able to tell which intersection to use. Alternatively, you could measure from a 3rd point, and this would narrow your intersection down to 1 point only.
Hand Measuring Elevations
Start by tying the string to your relative elevation point. It is easiest if you begin this process from the highest point and work your way down (obviously you cannot pull a string below ground surface level). If you are creating contours, you can use a form stake or piece of re-bar and tie the string 1 foot above ground elevation.
Once it is tied to your relative elevation point (point a), pull the string tight, use the line level to make sure it is level, and measure the distance from the string to the new point you are measuring (point b). If the string is tied 1 foot above your relative elevation point, make sure to factor that in. You can use the same relative elevation point now to measure to multiple other points (points c, d, e, and f can all be measured from point a)
By combining the above methods, it is actually possible to measure an entire property by hand, although it will be much more time consuming and not as accurate as using a total station.
Once we have taken all measurements we need using Theo and tape measuring, we head back to the office to start laying out the map using AutoCAD.
Using CAD to Format a Layout
After we have collected all of the raw information in the field that we need including site photos, we take it back to the office and begin to compile everything into a readable and presentable format. We use a popular software called AutoCAD to do this, although it could be done with any CAD software. The maps are then scaled, labeled and made ready for printed or digital layout.
The process of formatting is an interesting subject, so keep your eye out for a more detailed article about this yet to come.
Customization and End Product
After formatting, scaling, and labeling the map, it is ready to be used for designing a landscape planning. Because we format all of our maps to standard architectural scales, they can be printed out on a 24x36 paper and drawn on directly or with tracing paper. We also provide a dwg. or dxf file for those using AutoCAD, vectorworks, dynascape or other design software.
Every designer is different. That is why we customize each map and provide a pdf with layers that can easily be turned on or off and printed. simplified maps that leave out certain information such as text and elevations can be useful for many reasons.
If you are a designer or architect and are looking for a source of quality base maps, See how-it-works-in-4-simple-steps.html and check out 4 easy steps we can provide free mapping estimates, and get your project mapped quickly. Or click below and fill out a short form to receive your free, no strings attached estimate. We are always happy to receive estimate requests, and have a no pressure policy.
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If you are reading this, you are most likely either a busy professional landscape designer or you are a landscape architect needing a plan view base map for your project. It can be a lot to balance between designing, clients, and fitting it all into your schedule. So, we get it, you probably also don't have that much extra time to make your own base map, let alone figure out how to get one made by us!
That's why we made this simple guide so it'll be quick and easy for you. Well, actually there are 4 steps, and they are pretty easy. In this post, we break it all down.
And with no further ado...
Here is how it works
1.) Request a free estimate by clicking the button below, and enter in some basic information into the form. Or you can call us at 707.827.7913 and we are happy to help! No commitment required
2.) We will send you an estimate so you can factor the price of the map into the cost of your design. (We also work directly with property owners, in which case the designer can refer us to a client.)
3.) We coordinate a time to "shoot" the map of the property. Once our mapping process is completed, you will receive your digital map files via email to be printed or imported into your design software
4.) Dream your design! A solid map is the base from which you build!