Navigating Stillwater Reservoir

Too Long, Didn't Read

Stillwater Reservoir in the Adirondack Mountains of NY is unsafe to boat on, especially in low water levels.

Grab files from this website for safe routes, campsite locations, custom depth maps, and offline underlying satellite imagery (since there's no cellular data on the water).

Load all the files into recommended apps on either Android or Apple mobile devices, or modern Lowrance depth finders. Turn on your device location and use your GPS/GNSS position to safely navigate.

Use the text guides and instructional videos to figure out how to load the data and use the apps. Load all the data ahead of time, and practice using the app before you're on the water.

Check the upper left menu for more, including: campsite details, paper maps, photos/videos/articles/info/web-links about the area, and the history of the updates to this website.

If this site has helped you, and you're so inclined, please donate.


This site documents my project to create digital navigation data for Stillwater Reservoir, located in the Adirondack Mountains in the Town of Webb, Herkimer County, New York. Stillwater's elevation level fluctuates almost 15 feet in a typical year (1664-1679 ft), and has a large number of rock shoals and stumps that cause havoc for boaters.

In light of how imprecise previous navigation methods were, a convergence of technologies making it feasible, and suffering several destroyed boat props myself, I was motivated to start this project.

The only guidance available prior to this project has been paper maps, or estimated routes using visible landmarks and verbal guidelines. Both methods are difficult to effectively use on the water. I've used my skills in map making to create a highly accurate electronic boater's map of the reservoir that's easy to use on the water. By leveraging this data on a mobile device with a highly accurate GPS/GNSS position, you can avoid all hazards and safely navigate the reservoir.

The project began in summer 2014 with the program Google Earth, and its provided historical satellite imagery from November 9, 2011 and October 11, 2008. In this imagery, the water elevation was approximately 1668 and 1670 feet respectively. Nearly 7-10 ft below the typical summer month water elevations.

Since then, I've moved out of Google Earth to more capable software tools, and I've located other sources of imagery with lower water levels including satellite imagery, aerial photography and video taken during the draw down of the reservoir in 2001.

I've documented the imagery utilized in this project on the Available Imagery page. The majority of the imagery is available in the downloads section below.

A major project has also been undertaken to collect sonar depth data for the entire reservoir and create a custom contour depth map. Data was collected from 2015 through 2021, and is ongoing. Most of the reservoir has already been covered (~95%), and completion is likely in the near future.

Following completion of the down-scan contour depth map, the plan is then to move on to creating a side-scan mosaic of the entire reservoir. See the depth finder guide below for more details.

The results of these efforts are six categories of data layers:

1. Routes - Contains precise, color coded "safe routes" for motor boats. It also includes safe zones for water sports.

2. Hazards - Contains polygon data encompassing shoals that were visible in the low elevation map data, but were at least partially covered in high water conditions. (Deprecated in lieu of depth map layer)

3. Campsites - Contains the approximate locations of all forty-six designated campsites on the reservoir. For detailed campsite information, go to the Campsite Information page.

4. Image Overlays - Provides three categories of orthorectified images (accurately laid over the underlying satellite imagery)

I. Drawn maps found online or located through research, provided by state or county governments or private enterprises

II. Topographical maps found online

III. Examples of satellite imagery used to create this project

5. Depth Maps - Contains contour depth maps created from data collected 2015 through 2021, and is partially complete. Also contains data on submerged, extinct geographic features.

6. Boat Tracks - A collection of bread crumb trails from boat tracks on the reservoir, including my personal trips while following my own routes, depth collection tracks used to create the depth map, the DEC Forest Rangers' routes, and user tracks submitted by the public.

See the "How To Use the Data Layers" guide below for more information on interpreting the colors of the different data layers at different reservoir elevations.

I've also compiled step-by-step guides and a tutorial video for loading the map data onto mobile devices. Whether it's an Android or Apple, phone or tablet; a mobile device and the data on this site can be utilized to navigate and avoid most dangers on the reservoir.

Mobile devices and specialty apps have far surpassed the capabilities of stand-alone GPS units to load complex data sets. Also, mobile device GNSS chip-set capabilities predominantly surpass those of handheld units typically used for hiking. For these reasons, I only recommend using mobile devices on the reservoir.

This site is merely documentation of my work for my own personal use on Stillwater. If you choose to use any of the data on this site, please read the disclaimer below first.

I welcome all feedback. If you have any questions, comments, or information to add, please use the email at the top of the contact page.


Navigation Data Layers in Google Earth

(Map Data Last Updated: September 20, 2021)

(As of the forced site migration by Google on 9-Sep-2021, you will have to re-download this file for Google Earth)

Download (KML)

Contains all the data layers!

Loads in Google Earth desktop program on Windows/Mac/Linux (not the web version or mobile app)

See the Google Earth guide below for more information.

Direct Links for Mobile Devices

See the "Android Phone/Tablet" or "Apple iPhone/iPad" guides below for more information.

Routes: Download (KML)

Campsites: Download (KML)

(Additional data layers can be downloaded from Google Earth)

Offline Map Tiles

These files provide underlying ortho-imagery (satellite maps) on a mobile device while on the reservoir and away from cellular data or WIFI. See either the Android or Apple guides below for information on how to use these files. (click on Download below, then on the next screens, click the blue download buttons). All the downloads below are the mbtiles file type. Also see the "Available Imagery" page for associated water levels and sources of each set of map data.

Recommended Starting Imagery For Use On The Reservoir

MapQuest Open Aerial (2011) - Levels 12-18 (53 MB) - Download


Contour Depth Maps

2020 Vector - Levels 12-19 (38 MB) - Download

2020 Shaded Relief - Levels 12-19 (100 MB) - Download

Vector map is easy to read on the water, while the Shaded Relief map shows much more detail.


Topo Maps

New USGS - (c. 2000's to present) - Levels 6-15 (23 MB) - Download

Old USGS - (c. 1910's to 2000's) - Levels 10-16 (58 MB) - Download

Historical USGS - (c. 1890's to 1910's) - Levels 8-14 (83MB) - Download


Other Imagery Used In This Project

USGS Aerial (1942) - Levels 11-17 (135 MB) - Download

USGS Aerial (1952) - Levels 11-16 (14 MB) - Download

APA/Aero Graphics (1978) - Levels 13-17 (198 MB) - Download

NYS Orthos DHSES (1994) - Levels 10-15 (26 MB) - Download

NASA Blue Marble (2000) - Levels 11-15 (5 MB) - Download

Aerial Composite Image (2001) - Levels 13-17 (18 MB) - Download

USGS Landsat 7 (2001) - Levels 12-15 (2 MB) - Download

NYS GIS (2003) - Levels 1-18 (138 MB) - Download

USDA (2006) - Levels 12-17 (58 MB) - Download

USDA (2008) - Levels 3-18 (177 MB) - Download

NYS GIS (2009) - Levels 11-17 (156 MB) - Download

USGS (2010) - Levels 11-17 (163 MB) - Download

Google Satellite (2013) - Levels 7-19 (380 MB) - Download

NAIP (2013) - Levels 11-17 (153 MB) - Download

NYS GIS (2013) - Levels 11-17 (150 MB) - Download

NAIP (2015) - Levels 9-18 (374 MB) - Download

Google Satellite (2015-6 Combo) - Levels 10-19 (445 MB) - Download

Google Satellite (2015) - Levels 14-19 (445 MB) - Download

Google Satellite (2016) - Levels 15-19 (445 MB) - Download

NYS GIS (2017) - Levels 15-19 (305 MB) - Download

USGS (2017) - Levels 15-17 (217 MB) - Download


Some offline map files were created using MOBAC. This is a great program, check it out in order to create personalized offline map sets.

Other map files were created using Global Mapper. It's a great program, more powerful than MOBAC, but is also more expensive.

You can quickly view these files on your Windows Desktop using the MBTilesViewer program. Simply unzip and start the program, then drag and drop the downloaded mbtiles file into the program window. You can navigate with the left mouse button and zoom with the mouse wheel, just like in most map programs. For some of the files, you may have to manually zoom into the reservoir for the tiles to appear.

You can also use the free program QGIS to view these files, see the guide below.


Mobile Devices

Android Phone or Tablet

Apple iPhone or iPad


Google Earth



Recommended Boat Installation

Depth/Fish Finders with GPS and memory

Garmin & Other standalone GPS units

Disclaimer -- Please Read!


I make no guarantee that the data on this site provides accurate guidance or safe passage. I've created this data for my own personal use, and it is for general reference only, not for true navigation. Using the data found on this site for true navigation means you assume all liability for property damage and personal injury. Stillwater reservoir is a dangerous place to take a boat.

The files found on this site are not a foolproof solution and do not replace use of common sense, local knowledge, and proper boating safety. This entire project was created from satellite and aerial imagery, and collected depth data. It has not been thoroughly tested over the entire reservoir using additional equipment, and data may be incomplete in certain areas.

It should also be understood by anyone using the data on this site, that their GPS devices are not free from error. A GPS receiver's position solution may contain residual errors that can make them unreliable at times. The sources of error (additional reading) vary with time, geographic location, and receiver capabilities and quality. These factors are outside the control of both the user of the device, and the creator of this site.

Even if the map data provided on this site is perfect (which I am sure it is not), an incorrect position provided by the user's receiver may still create a hazardous situation. You can take an introductory course, or an online college course about GPS if you want to learn more.

Another contributor to the overall error of my routes layer, is the horizontal accuracy of the professionally rectified satellite imagery. Every set of imagery can have its own associated error with respect to the true positions of items shown in the imagery, although it does seem to be improving over time. I believe this source contributes very little to overall errors, as multiple sets of imagery from multiple sources all agree very closely.

Contributing to the certainty of this assumption, my independently collected depth imagery also coincides very closely with the imagery. I have noticed there are certain imagery sources that disagree slightly with the majority of data sets. However I have factored this discrepancy into the creation of my routes layer by de-weighting the significance of that imagery.

In addition, multiple human and technological factors contribute to errors in navigation. These factors include, but are not limited to: Incorrect layer color interpretation, poorly selected zoom levels, improper layer selections, slow update rate of the map display, slow update rates of your device's computed position, paying attention to the app while safely driving the boat, poorly executed turns, failure to properly follow a path, decreased situational awareness, poor reaction times, and distracted driving.

Add to the list the many other factors that contribute to the overall dangers of boating on open water, such as foreign objects in the water, wind & waves, hazardous weather, mechanical issues, other boaters, etc.

There are also many dangerous stumps in Stillwater Reservoir. The stumps move varying distances every year with the winter ice, and they get dropped in new places in the spring thaw. Also, following high water there is a lot of floating drift wood just under the water's surface. This project makes no attempt to document all the locations of stumps.

Copying or use of the data layers for anything other than personal, non-commercial purposes is prohibited without my express written permission.

This website, its downloadable contents and the outside hyper-linked websites are not meant to be a comprehensive guide and shall in no way guarantee safe passage through, around, over and under the Stillwater Reservoir. All users of this website are responsible for utilizing any and all reasonable measures when traversing through, around, over and under the Stillwater Reservoir. The makers of this website shall in no way be responsible for any accidents, incidents or occurrences (naturally occurring, man-made or otherwise) that may arise during the use of this website, its downloadable contents and the associated hyper-linked websites while traversing through, around, over and under the Stillwater Reservoir. Users of this website shall assume any and all risks that are either directly involved or incidental to traversing through, around, over and under the Stillwater Reservoir. The information presented on this website is based on the observations and work product of the creator of this website and not that of an expert mariner, professional topographer, professional geographer, geographical information systems professional, freshwater marine specialist or any other applicable expert. No guarantee is being made that any and all dangers inherent or possible to the Stillwater Reservoir have been cataloged or mentioned in the materials contained on this website, its downloadable contents and the associated hyper-linked websites. Users of this website shall assume any and all risks that are either directly involved or incidental to utilizing the websites hyper-linked to this specific website. The creator of this website shall not make any guarantees as to the contents and accuracy of the hyper-linked websites mentioned above or to any current and future websites that may hyperlink to this specific website. Furthermore, when traversing through, around, over and under the Stillwater Reservoir all users of this website are expected to abide by the laws, codes, rules and regulations of the Town of Webb in the State of New York, County of Herkimer in the State of New York, State of New York and the United States of America that are both applicable to freshwater marine navigation and otherwise.