Find height of lakes using lake shapefile and DEM / contours

[AndrewElvidge]

Hi,

I've started using ArcGIS again after a 5 year break, and I've forgotten most things.
Im trying to find the height of lakes.
I have a shapefile layer for all the lakes
I have a shapefile layer showing height contours, as well as a raster DEM/DTM.
The aim then is to assign a height to each lake shape file (perhaps adding height as an extra attribute to this data).

Thinking about it, I imagine that I would need to use the raster DEM rather than the shapefile contours. Then I could take a mean of the DEM raster values cohabiting the area of each lake to assign the heights. Is there a tool for doing this type of thing?

Any help would be much appreciated.

Thanks

[markdenil]

you might use Extract by Mask on the DEM
Extract by Mask takes a feature layer as mask input.

Loop through the feature class, selecting one lake,
make a layer of just that lake
run the Extract by Mask using that layer
calculate the elevation of the output raster
throw away the Extract by Mask output
do the next lake....

[ChrisSnyder]

The most appropriate tool would be "ZonalStatisticsAsTable" tool in Spatial Analyst:http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//009z000000w8000000.htm

Use the "MEAN" statistic.

No need for looping, you can process the entire thiing in one step.