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Review Draft Eastern Gateway Wetland Restoration Site — Annual Report <br /> Though not officially considered to be a hydric soil, Holcomb silty clay loam is <br /> described as having a high water table within 1 to 1.5 feet below the soil <br /> surface, and has hydric field indicators (10 YR 3/2 with strong mottles at 10 "). • <br /> Thus, the post - construction soils present on the site are reflective of wetland <br /> conditions, and seem to match fairly closely the soils described in the Lane <br /> County Soil Survey. <br /> Hydrology <br /> One of the goals of the project was to re- establish wetland hydrology on the site <br /> by removing the fill material and lowering the ground elevation relative to the <br /> seasonal (perched) water table. Wetland hydrology during the first season after <br /> construction was documented by a staff gauge installed in the deepest portion of <br /> the site (the central pond) and by descriptive observations and permanent photo <br /> plots. <br /> The 1993 -94 season was somewhat drier than normal. The fall rains came late <br /> in 1993, and wetland hydrology was not present on the site until December. At <br /> that time, more or less the northern half of the site (corresponding roughly to <br /> the area supporting emergent meadow vegetation) became ponded, a condition <br /> that persisted until mid - spring. The remainder of the site (corresponding <br /> roughly to the area supporting wet prairie vegetation) supported mostly saturated <br /> soils, but with only pockets of ponding. After another dry spell, the water level <br /> reached its highest point in January and then maintained that level, with minor <br /> fluctuations, until April. The extent of ponding is shown well in the photos <br /> from the permanent photo stations taken on April 4, 1994. <br /> During April and May the water level dropped gradually, though perhaps more <br /> quickly than in a normal year because of the dry spring, and by late May <br /> ponding was present only in and around the most deeply excavated portion of <br /> the site (the central pond). Through June and part of July, water was present <br /> only in the bottom portion of the central pond, and elsewhere on the site, <br /> surface soils were not saturated. The water in the central pond dried out <br /> completely by late July. <br /> Given that the 1994 growing season was drier and warmer than normal, we <br /> anticipate that in many years the standing water and saturated soils will persist <br /> for a longer period of time, perhaps into early summer. We were also <br /> concerned about the survival of seedlings of the perepnial fork/hat were <br /> seeded, given the long drought experienced during the summer. However, <br /> examination of the site in the fall indicated that mortality of seeded plant <br /> species was minimal. <br /> (Add to and refine this section with staff gauge data, from Al Schloss when we <br /> get it) <br /> Page 13 <br />