Laserfiche WebLink
1995 Reclamation Bids July 7, 1995 Page 5 <br /> some justification for the need to do so. My understanding is that ditches <br /> 1,4, 5, 6, and 7, in their current configuration and location, are stable and <br /> vegetated, non-erosive, and functional. Ditch 8, due to it's steep gradient <br /> in it's lower reaches has exhibited erosion in the past. However, <br /> constructing the ditch lining proposed in TR25 should alleviate the majority <br /> of the erosion concerns. <br /> Ditch Configuration and Lining <br /> The configuration of ditches 2, 3, 4, 5, 6, 7, and the spring conveyance <br /> ditch does not appear to be excessive, and appears consistent with the <br /> designs approved in TR25. My concern with these ditches lies in the <br /> requirement for an excelsior net in the ditch. The primary purpose of such <br /> a net is to provide erosion resistance and protection to the seed bed while <br /> plants are germinating and maturing. If the Division's concern with these <br /> ditches is erosional, then placement of a fiber lining of the type they <br /> suggest is not the appropriate solution. These ditches will be seeded with a <br /> seed mix which should produce a rapid cover, thereby negating the <br /> necessity of a net liner. <br /> Ditch 1 is an existing ditch. CDMG apparently proposes reconstruction of <br /> the ditch. The CDMG cross-sectional design of Ditch 1 is at minor <br /> variance with that approved in TR25. Width is comparable, but depth of <br /> the CDMG design is greater by 0.3 feet. As with all ditches, CDMG is <br /> proposing to line Ditch 1. The liner of this ditch is proposed to be a <br /> coconut fiber mat. Based on Mr. Lewicki's observations, this ditch Uq <br /> appears stable, functional, and of adequate constructed design as is. <br /> Therefore, we both question the necessity of reconstructing this ditch. <br /> Additionally, as with the ditches discussed previously, the use of a fiber <br /> mat is primarily intended as protection for the seed and seed bed, not <br /> erosion control. As CDMG is proposing mulching at all areas to be <br /> revegetated, and the seed mix has several rapidly growing components, I <br /> am not convinced a fiber mat is justified in this application. <br />