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<br />conducting transpiration, which decreases soil moisture content and increases soil moisture <br /> <br />. 9 <br />storage capacity. <br /> <br />e <br /> <br />Studies at Colorado State University have shown that vegetated channel linings may increase <br /> <br /> <br />sediment deposition up to 700 percent over hard armor systems. Using TRMs is a natural and <br /> <br /> <br />inexpensive way to retain sediment, enhance water quality, reduce non-point source pollution, and <br /> <br />facilitate groundwater recharge. <br /> <br />The City of Chattanooga, Tennessee strongly endorses to the use ofRECPs. In its stormwater <br />management efforts, the City of Chattanooga has totally abandoned the practice of constructing <br />concrete, rip rap, rip rap/concrete open channels and enclosed systems, "because these types of <br />surfaces and systems do not help in any way to reduce pollution."lo As a result of rainwater <br />monitoring, the City has determined that vegetative channels help greatly in the reduction of <br />pollution. Therefore, the City is now either requiring or encouraging open vegetative channels in <br />lieu of closed (pipe) systems. All of the channels are reinforced with geosynthetic RECPs. Used <br />as turf reinforcement mattings to reinforce vegetation in high velocity channels and steep slopes, tit <br />they extend the use of vegetation into situations and applications where its establislunent would <br />not otherwise be possible. <br /> <br />One product the City is using exclusively for high velocity and/or high volume channels is <br />Pyramat@ high performance TRM, manufactured by Synthetic lndustri,~s. The product is a three- <br />dimensional woven geotextile matrix composed ofUV stabilized polypropylene monofilament <br />yarns. This soft armor solution combines long-term strength, durability, dimensional stability, and <br />the longevity of a high performance geotextile. The unique three-dimensional geometry, in <br />conjunction with vegetation, reduces the velocity of waters, thereby controlling erosion and <br />reducing pollution. <br /> <br />Performance of this patented matrix has been extensively evaluated at a. renowned hydraulics <br />laboratory in the western United States. Vegetated, this product may resist flow velocities of up <br />to 25 ft/sec at shear stresses up to 10 Ibslft2 Not only has this high performance TRM been <br />evaluated at a major U.S. hydraulics laboratory using sandy soils and vc:getation, but the Texas <br /> <br />e <br /> <br />- 5 - <br />