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<br />major exception is the native tree growth along the chapnel banks. The overall project has been <br />given an unacceptable rating because of the tree growtp issues, although most of the individual <br />project features received an acceptable or marginally acpeptab1e'rating this year. <br />, <br />! <br />At the request of the CWCB, the UDFCD has perfotmed annual maintenance tasks along the <br />project reach. Such activities have included: ' <br />. removal of non-native trees and trash trees from the channel bottom and other areas, <br />. repair of drop structures and other riprap features, , <br />. removal oflarge flood deposits and other debris fr9m the channel, and <br />. Temoval of sediment and trash that blocks culvert Qutlets and hinders flap gate operation. <br /> <br />. <br /> <br /> <br />e <br /> <br />In 1999, the CWCB and UDFCD completed a joint! effort to hydraulically model the project <br />reach of the South Platte River. This effort resulted [from a meeting held in 1996 whereby the <br />Corps agreed to allow trees to remain on the channel banks if the HEC-2 analysis showed no <br />significant impact to the water surface profile due to i*creased roughness. The CWCB expended <br />funds to obtain new topographic mapping for the project reach (2' contouT interval), and the <br />UDFCD expended funds to contract with ICON Engineering to perform the hydraulic analysis. <br />The cost of this effort was on the order of $100,000.1 The study was submitted to the Corps for <br />their review, and comments were retumed to the CWCB. The CWCB and UDFCD responded to <br />those comments. No further actions or decisions have taken place regarding the hydraulic model. <br /> <br />PROJECT NON-COMPLIANCE <br />At this time, the South Platte channel improvement project has received an unsatisfactory rating <br />from the Corps of Engineers. In the event of a flood disaster that damages the project, the <br />CWCB is not eligible to receive emergency Tepair fml.ds and assistance from the Corps' PL 84-99 .. <br />program. Until such time the project receives a ~etteT inspection rating, repair of damaged .. <br />project features would be the responsibility of the CWCB. <br /> <br />POTENTIAL SECTION 1135 PROJECT <br />The Omaha Corps has offered to participate in a Section 1135 project (PToject Modification for <br />hnprovement of Environment) with the CWCB. T~e purpose of the 1135 program is to modify <br />features or operations of previously constructed C'orps projects to improve the quality of the <br />environment in the public interest. The non-feder~l cost share requirement for this program is <br />25% (in-kind services and lOT cash). The non-fedetal sponsor's share of the cost is not payable <br />unless the project enters the construction phase. I <br /> <br />Specifically for the South Platte River, an 1135 project would address the issue of vegetation <br />management along the project reach. Work couldlinclude removal of non-native (and possibly <br />some native) species of trees along the banks of ttie river, with replacement trees added outside <br />of the 100-year floodplain. In addition, the projectiOperation and Maintenance manual would be <br />revised and amended to incorporate the new I concepts of vegetation management and <br />enviTonmental considerations. ! <br /> <br />We assume that an 1135 project would bring the ~ubject river reach back into compliance with <br />Federal requirements, <br /> <br />, <br />, <br />, <br />i <br />! <br />) <br />Flood Protection. Water Project Planning an~ Financing. Stream and Lake Protection <br />Water Supply Protection. r:;onservation Planning <br /> <br />e <br />