Laserfiche WebLink
<br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />::,<,.. .) <br />~~:v"" <br /> <br />intervening limestones will IlCcur at less depth. As a mstter of judgment, <br />the proposed reservoir will prove satisfactory from a seepage standpoint, <br />but this conclusion must be checked by deep drilling and detailed geolog- <br />ical work. <br /> <br /> <br />The immediate foundation for the dam consists of msssive <br />sandstone strata (one to four feet thick) with intervening shale layers. <br />These beds dip do,mstream 35 to 40 degrees and strike northwesterly 40 <br />degrees. The rock is considerably jointed. One system strikes north- <br />east and dips 80 to 90 degrees to the southeast; the other strikes north. <br />west, dipping 40 to 54 degrees to the northeast. A fault of unknown <br />character, dipping 70 degrees downstream, crosses the ca~on immediately <br />upstream from the dam. The extent and significance of this fault .must <br />be determined before the geological situation is thoroughly understood. <br /> <br />Eight exploratory holes were drilled in 1948 at the damsite. <br />The foundation rocks appear adequately stable for construction of an <br />earth dam. However, further drilling is required to evaluate fully <br />reservoir and damsite seepage conditions. Water pressure tests indi. <br />cate that grouting will be necessary to control seepage of water under <br />and around the dam. <br /> <br />Prospecting and testing of the several types of available <br />msterials will be necessary prior to design and construction. It is <br />probable that satisfactoI"lJ deposits of silt, sand, and gravel can be <br />located in the reservoir area for impervious, semipervious, and per- <br />vious embankments required for the proposed earth dam. Gravels in <br />the various river terraces and in the river channel, derived in part <br />from granitic and metamorphic areas in the upper reaches of the <br />Fryingpan River., probably ldll be suitable for concrete aggregate. <br />Cliffs of ~hroon sandstones which are exposed downstream from the <br />damsite appear suitable for riprap. <br /> <br />Construction aspects <br /> <br />Oonstruction of the dam and reservoir will require the <br />acquisition of about 1,500 acres of land, most of \lhich is in private <br />ownership. The area includes about 250 acres of farm lands which <br />are devoted largely to production of native hay under irrigation. <br />The remaining area is timber or grazing land. Clearing of about 600 <br />aqres of medium timber will be necessary. It will be necessa~ also to <br />relocate appr'ox1mately 7-1/2 miles ot two-lane gravel-surfaced State <br />Highway No. 104 which now traverses the reservoir area and a like <br />mUeage of telephone line. <br /> <br />16 <br />