SBCT Final EIS - Govsupport.us

Chapter 3 ⎯ Affected EnvironmentMontane wet ohia forest is generally restricted to gulches and ridgetops between 3,200 and 4,000 feet.The dominant tree is ohia. Ohia shrubland falls between 2,500 and 3,000 feet in SBMR. The steep,windswept ridges have shallow soil, and rainfall is generally between 100 and 200 inches per year.Dwarfed native tree and shrub species thrive here.There are three community types within the lowland wet communities, where conditions are generallywarm and sheltered from wind, with annual rainfall exceeding 100 inches. Ohia forest is below theKoolau summit between 1,900 and 2,700 feet and below 5,000 feet in the Waianae Mountains(USARHAW and 25th ID [L] 2001a). Uluhe shrubland is widespread on many of the Hawaiian Islands,usually in wet lowland areas below 2,200 feet. Loulu hiwa forest gets between 75 and150 inches of rainfall annually. It occurs exclusively in the Koolau Mountains on steep, rocky windwardslopes. This is considered a globally imperiled vegetation community (USARHAW and 25th ID[L] 2001a).There are four types of lowland moist communities on the training areas: Kawelu grassland, Ohialowland moist shrubland, Oahu diverse forest, and Koa/Ohia forest (USAG-HI 2004). Lowland dryshrubland is generally dominated by aalii and is found on the main Island of Hawaii. Adjacent communitiesare often dominated by nonnative grasses and shrublands in fire-disturbed areas like SBMR.WetlandsThe U.S. Army Engineer District, Honolulu completed a wetland inventory of USAG-HI propertieson Oahu. The report identifies two wetland areas around SBMR and eight areas in SBER (USACE2005c).The first wetland area at SBMR is in the upper reaches of Waikele stream in the South Range. Fieldverifiation of this site found it lacks wetland hydrology, and therefore was not classified as a regulatedwetland (USACE 2005c).The second is a large wetland area near Mount Kaala at the westernmost boundary of SBMR. NationalWetland Inventory (NWI) data and field verification indicates the wetland extends off SBMRonto the Kaala Natural Area Reserve to the northwest and the Waianae Kai Forest Reserve to thesouthwest. The wetland is within the Schofield Barracks Forest Reserve where no SBCT activitieswould occur.The largest of the eight wetland areas on SBER is the Ku Tree Dam and Reservoir area. The reservoirwas created in 1925 by the construction of Ku Tree dam. The dam was abandoned in approximately1938, and the water level in the reservoir has dropped 80 feet. The area is considered to have revertedto its pre-reservoir condition of a network of streams, and is not a regulated wetland. Ku Tree damand reservoir are located in training area ER–4, north of the lower 72 landing zone (USACE 2005c).Koolau Reservoir is located in training area ER–12, south of the upper 72 landing zone and the WinteraTrail in SBER. As with Ku Tree Reservoir, the ditches, tunnels, and dams that once createdKoolau Reservoir have long been abandoned. Data collected from multiple site visits indicate the areapossesses the vegetation, soils, and hydrology of a regulated wetland (USACE 2005c).An unnamed wetland feature was identified on NWI maps of the area. It is located within trainingarea ER-12 in central SBER on the northern bank of the south fork of Kaukonahua Stream. Field verificationof this wetland found the area to lack hydric soil and hydrology, and therefore is not a regulatedwetland (USACE 2005c).February 2008 3–60 2/25th SBCT Final EIS