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I I I I I I I I I I I I I I I I I I I Unit 7 - THE HIGHLANDS - This unit is characterized by highly dissected topography with many independent tributaries that drain into Sagers Wash. The unit contains approximately 29,707 acres. There is some canyon and rock terrace development, but the canyons are not of significant depth (100 to 200 feet). There are sandstone and shale derived soils. The major rock formations ~ within this unit are as follows: Entrada Sandstone, curtis ru Formation, Summerville Sandstone, Bluff Sandstone, Morrison 0~ Formation, Burro Canyon Formation, Dakota Sandstone and Mancos C:' Shale. The estimated annual Present and FWOP condition sediment yield for this unit is approximately 0.6 acre-feet per square mile or approximately 1.8 tons per acre (PSIAC sediment yield classification 3 - moderately high). This is not a significant sediment yield and the salt yield is estimated at 2%. The estimated sediment yield from this unit is 14,259 acre-feet or 42,778 tons and 856 tons of salt. There is major sediment deposition in the Mancos Shale zone adjacent to the Highlands before the sediment enters Sagers Wash. In other words, the Highlands is not an efficient sediment and salt delivery system. There is potential for rangeland vegetation improvement in this unit. It is estimated that the vegetative improvement treatments would serve to improve the rangeland but would not significantly alter the sediment delivery or hydrologic status of the unit. This area is not recommended for land treatment project planning. Unit 8 - CISCO PITS - This unit is a treated portion of the Mancos Pediment. The unit contains approximately 9953 acres. It was treated during the 1950s and 1960s. Treatment involved the construction of a significant number of pits to control the erosive energy of the overland flows of storm events. This unit has an average slope of about 15%. This slope would normally be a highly erosive and high sediment and salt yielding source area but the land treatment measures have successfully stabilized this potential problem. The estimated annual Present and FWOP condition sediment yield rate is approximately .43 acre-feet per square mile or 1.3 tons per acre (PSIAC sediment yield classification 4 - moderate). The estimated sediment yield prior to treatment is 2.0 acre-feet per square mile or 6 tons per acre (PSIAC sediment yield classification 2 - high). The salt yield is estimated at approximately 5%. The estimated sediment yield from this unit is 3117 acre-feet or 10,350 tons and 518 tons of salt. Therefore, the treatment has controlled approximately 16,593 acre-feet or 49,779 tons of sediment and 2489 tons of salt. This unit is not recommended for project-level land treatment planning. The treatment results of this potentially high sediment yield land form are impressive and deserve a major evaluation in light of the success and the significant time increment since their installation. Such a study would determine the economics and future application of the pit treatment practice. It should be noted that the pits are presently approximately 1.5 to 2 feet deep with some vegetation in them and that the major gully systems have not just been stabilized but 13 .~_. .