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1. ## CE-QUAL-W2 bathymetry widths calculation method

The problem is the TIN resolution Solution for this problem is to make the WMS to use a finer resolution for calculating the storage: These are the results for one of the segments number after I increased the TIN resolution. This table have widths for first 11 layers. The 3000*1500 is the resolution in my new TIN and 300*150 is the one that I and the WMS team used. You can see about 20% difference between the values is almost equal as the amount I was concerned about. 3000*1500 300*150 difference 1863.5 1506.2 19% 1800.0 1461.8 19% 1727.2 1425.8 17% 1650.8 1395.9 15% 1566.9 1385.8 12% 1496.1 1190.1 20% 1423.9 1166.2 18% 1366.0 1151.6 16% 1322.9 1071.9 19% 1280.5 1049.6 18% 1242.0 1028.5 17% What I did is: 1- to convert the TIN to a DEM ( here you can define an interpolation ratio). I adjusted the new DEM resolution to 3000*1500 (it was 300*150). 2- Convert back the new DEM to TIN. And from this TIN I used the rest of the work. The calculation time will increase significantly but the results are more convincing.
2. ## CE-QUAL-W2 bathymetry widths calculation method

Hello Chris Thank you for the reply. The TIN is made from x y z points in (Longitude , Latitude, Elevation in meters) e.g. (-106.5 , 51.6, 555) At first I used the (Geographic (Latitude/ Longitude)) projection but the distance calculated between two points were not correct. So I reproject the maps to UTM. Projection : UTM Zone: 13(108w-102w)Northern hemisphere Datum: NAD83 Planar Units: METERS I checked the distance between two points that I know the distance in reality (51 4' 45"/106 37' 10" and 51 6' 17"/106 39' 0.5") . The distance should be around 3500 meters which is correct in UTM projection . (In the Geographic projection it was 0.0394 m). So I have everything in meters and when I am using the ruler I have correct values for distance. The segment Length is also correct but the layer width is not. I also checked the calculated storage capacity which is not correct and consequently the layer width. Amir
3. ## CE-QUAL-W2 bathymetry widths calculation method

Hi I have some concerns about bathymetry widths calculation. The bathymetry widths calculated by WMS are up to 50% less than the real measurements. The projection seems to be correct and when I use the ruler I get correct values. The TIN resolution is fine and good. Now I am suspicions of the following issues: 1- The storage calculation from TIN is not correct and consequently the layers widths. 2- The TIN map resolution is not fine enough. 3- The projection is not correct or the ruler tool is not correct or the ruler shows the values in a different projection system (i.e The ruler shows the length at meters while the widths are calculated in a different unit).
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