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**[[Ranking_of_items_with_shoaling_effects_included#Interpretation_of_Rankings|Interpretation of Rankings]]
**[[Ranking_of_items_with_shoaling_effects_included#Interpretation_of_Rankings|Interpretation of Rankings]]
**[[Ranking_of_items_with_shoaling_effects_included#Using_Details_views_to_better_understand_final_Rankings|Using Details View to Better Understand Final Rankings]]
**[[Ranking_of_items_with_shoaling_effects_included#Using_Details_views_to_better_understand_final_Rankings|Using Details View to Better Understand Final Rankings]]
='''Ranking of items with shoaling effects included'''=
So far the examples presented in this guide have not included shoaling considerations, just to keep things straightforward while introducing the overall layout and functionality of CPT.  However, for practical decision-support applications of CPT towards OM budget development, shoaling information needs to be included to help achieve rational allocation of funding.  This section will describe how CPT can include shoaling considerations along with commerce data when ranking channels for maintenance dredge funding.
==''Explanation of Default Shoaling''==
Because controlling depths for the thousands of channel sub-reaches in the USACE navigation portfolio vary due to local hydraulic conditions, it is a significant information management challenge to include all of this data within comprehensive decision-support package for OM dredging.  The CPT development plan calls for several mechanisms to be employed for inclusion of up to date shoaling conditions and channel limiting depths, including linkages to automated channel survey analysis packages, online historical datasets, and manual user upload of channel conditions via the CPT interface. 
Until these additions have been developed, CPT allows for inclusion of shoaling effects through use of a default shoaling parameter.  As discussed in Section 2.3.1, the default shoaling feature assumes a uniform shoaling rate across the entire grouping of selected channels (or Projects, Districts, etc.).  The practical effect of employing this feature is that entities are now ranked in terms of the tons or $-value transiting at the deepest of maintained depths.
==''Interpretation of Rankings''==
To help demonstrate the effect of shoaling on the Rankings compiled by CPT, return to the Charleston Harbor, SC example used previously in Section 2.  Use the Reach level analysis tab and select all of the sub-reaches in Charleston Harbor.  Under the Preferences tab, uncheck the Ignore Shoaling box and set the Default Shoaling rate to 3 ft/yr by simply typing a “3” in the input box (do not enter units).  Select only year 2007 to ensure consistency with the previous example, and save Preferences.  The Rankings tab will reveal the table shown in Figure 50.  Comparison of this table with that shown in Fig. 13 shows significant differences in the rankings once the focus is shifted to the deepest 3-ft of maintained depth in each channel. 
[[Image:Figure50_RankingsWith3ftShoaling.jpg|400px|thumb|left|Fig. 50 – Rankings of Reaches in Charleston Harbor with 3 ft of shoaling assumed, 2007]]
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Another useful comparison to the previous example using Charleston Harbor is to generate .kml overlays for viewing in Google Earth.  Use the default KML Settings under Preferences and export the Rankings table to KML.  The resulting Google Earth view is shown in Fig. 51.
[[Image:Figure51_RankingsWith3ftShoalingGoogle.jpg|400px|thumb|left|Fig. 51 – Charleston Harbor Reach Rankings with 3 ft of shoaling assumed, 2007]]
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It is very interesting to note that the Entrance Channel and other sub-reaches that were prominently shown in Fig. 18 when all cargo was included are now of secondary importance, in terms of tons transiting in the deepest 3 feet of maintained depth.
==''Using Details views to better understand final Rankings''==
Selection of the entry for Shipyard River in the Rankings table in Fig. 50, which carries roughly 1.8 million tons of cargo that would be disrupted by 3-ft of shoaling, will reveal the draft profile shown in Fig. 52.
[[Image:Figure52_DraftProfile.jpg|400px|thumb|left|Fig. 52 – Draft profile for Shipyard River in Charleston Harbor, SC, 2007]]
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Revision as of 18:37, 6 July 2011

Channel Portfolio Tool (CPT)

POC: Dr. Kenneth Ned Mitchell br\Kenneth.n.mitchell@usace.army.mil br\601-634-2022 br\US Army Engineer Research and Development Center (ERDC) br\Coastal and Hydraulics Lab (CHL)

Active URL (CAC authentication required): https://cpt.usace.army.mil/

Developmental URL (Corps machines only): https://itlgis01.usace.army.mil/CPTIWRWeb

CPT is developmental software that is updated frequently.

CPT User's Guide

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