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<br />. <br /> <br />where several sources of information conflicted or were inconsistent, <br />an effort was made to resolve the question by contacting appropriate <br />agency officials or by field inspection. Where t.he classification <br />of a stream or basin is of a marginal nature, generally the lower <br />ranking is assigned. Thus, if a channel seemed to be between Class A <br />and B, it is assigned a Class A ranking. <br /> <br />Channel stat.us is based on current development levels, and it must <br />be recognized t.hat future development within a basin in many cases will <br />cause channels that. are currently adequate or marginal to become <br />completely inadequate. This is particularly true in those areas where <br />development causes an increase in the peak rate and volume of runoff, <br />while, at the same time, there is a constriction of the channel due to <br />flood plain encroachment. <br /> <br />The distribution of the 398 subbasins in the region by basin/flood <br />plain and channel status is shown in the following table, which gives <br />the number of subbasins in each category: <br /> <br />Drainage Basin Problem Classification Matrix <br /> <br />. <br /> <br /> BASIN/FLOOD PLAIN STATUS - <br />Basin Functional Status Development <br />(Channel Status) Full Probable Moderate Minimum <br /> A B C D <br />No Defined Channel A 1 (14) 4 (24) 9 (18) 13 (17) <br />Poorly Defined B 2 ( 5) 5 (20) 10 (34) 14 (32) <br />Marginal Capability C 3 ( 8) 6 (35) 11 (41) 15 (33) <br />Adequate but Restricted D 7 ( 1) 8 (16) 12 (14) 16 (23) <br />Fully Adequate E 17 ( 0) 18 ( 5) 19 (13) 20 (45) <br /> <br />NOTE: (1) Numbers indicate Problem Potential Ranking, e.g. 6. <br />(2) The number of basins in each group are in ( ), e.g. (35) <br />(3) The total number of basins is 398 <br /> <br />. <br /> <br />Note that for channel Classes D and E, which represent well-defined <br />channels capable of conveying the runoff from a major storm without <br />flooding, except as limited by structures for Class D, the number of <br />subbasins increases significantly as the level of basin/flood plain devel- <br />opment decreases. This indicates that natural channels are generally <br />adequate for conveying runoff from basins in a natural state, but that <br />as development by man begins to occupy the basin two things happen <br />concurrently: (1) channels are constricted and obstructed with <br /> <br />13 <br />