Are the data layers available in a digital format?
Yes. The orthophotography is available in TIF or MrSID format. TIFs can be viewed using any image viewing software. MrSID images or TIFs are mainly used in GIS or CAD software designed to view the images. Any user who has AutoCAD 2002 or later version can use the MrSID images. We commonly provide the images in TIF format because people seem to be more familiar with that data format.
All other GIS layers are available in standard Esri shapefile format. Shapefiles can be inserted into AutoCAD or can be viewed in a variety of GIS software.
How much does it cost for digital data?
According to the Enhanced Access Policy, the orthophotography costs $100 per section or $1 per acre. It is more cost effective to buy an entire section if the request is for more than an 1/8th (80 acres) of a section. The cost of other GIS layers varies by layer (view our Digital Data Request Form for a list of available layers and fees.)
How are digital products sent to me?
If the files are small enough, the layers will be posted to our FTP site and you can download them at your convenience. Larger file sizes require CD or DVD media and are shipped according to the prices listed on the order form.
What is Orthophotography?
Orthophotos are a stereo pair of aerial photographs mathematically and optically corrected to eliminate distortion caused by the curvature of the Earth and the curvature of the camera lens, but still have the readability of an aerial photograph. The main difference between orthophotos and aerial photos is that measurements can be done on orthophotos.
Do you have historic aerials available?
Yes. We have true-color imagery for the entire county from 2000, 2005, 2008, and 2010. The southeast quarter of the county was flown in 2002 and the northeast quadrant was updated in 2003.
Historical black and white photos are available from 1966, 1980, 1985, 1990, 1995 for the entire county. We also have historical black and white photos from 1950 and 1975 available for most of the county. Historical black and white imagery was provided courtesy of Consumers Energy and SEMCOG.
What is the resolution of the imagery?
The pixel resolution of the imagery varies with each orthophotography project:
- 2000: 6” resolution in urban areas & 9” resolution in rural areas
- 2002: 6” pixel resolution county-wide
- 2003: 6” pixel resolution county-wide
- 2005: 6” pixel resolution county-wide
- 2008: 12” pixel resolution county-wide
- 2010: 12” pixel resolution county-wide
- 2015: 6″ pixel resolution county-wide
Do you have a wetlands layer available?
Yes, we have two layers that have been created to map the wetlands throughout Michigan:
- National Wetlands Inventory (NWI) – A digital version of the National Wetlands Inventory. This data was compiled in 1971. Class codes indicate the type of vegetation potentially found in that location.
- DEQ Wetlands – In 2006, the Michigan Department of Environmental Quality published a wetlands layer. The DEQ Wetlands data includes a description and acreage of each wetland area. Areas were determined to be wetlands based on their presence in the historic NWI or MIRIS data and the location of hydric soils.
How can I prove I am not in the floodplain so I don't need to purchase flood insurance?
If the property is within the floodplain on the Flood Insurance Rate Map, the only way to remove the flood insurance purchase requirement is to apply to FEMA for a letter of map amendment (LOMA.) A LOMA requires that the property owner submit surveyed elevation information that demonstrates that the structure is above the 100-year flood elevation. The elevation certificate and the LOMA can be downloaded from FEMA’s website. Contact the Department of Environmental Quality – Water Management Division at (517) 335-3448 if you have additional questions about floodplains or flood insurance.