Restoration of the 11.4-Acre Marsh, Wet Meadow and Riparian Woodland: The restoration of this wetland has focused primarily on reestablishing the original marsh which occupied the northeastern portion of Seigler Valley. By re-establishing the original hydrology, marsh restoration will also re-hydrate the surrounding wet meadow and reestablished riparian woodlands. As shown in Figure 3, this marsh occupied approximately 11.4 acres before the first efforts were made to drain it northward to Seigler Creek in the early 1900's. The marsh and surrounding wetlands were further dewatered by the construction of two additional drainage ditches between 1948 and 1952.
The original grade of the wetland outlet will be reestablished through construction of a small concrete flashboard dam at the downstream end of the drainage channel. The spillway height was initially adjustable through the use of removable 4x6 in cross-section boards stacked horizontally in a channel-iron slot inset into the sides of the spillway. This allowed final adjustment of pool height following observations made during the first few rainfall years.
Back-filling of the drainage channels was not a reasonable restoration measure due to the extensive amount of disturbance it would have caused to existing wetland vegetation and soil profiles. Additionally, the availability of deeper water and the presence of small islands formed from existing channel spoils has provided a significant benefit to wildlife.
Marsh hydrology and natural realignment of wetland plant communities has been studied in detail as part of the required monitoring plan. The wetland delineation and plant community map completed for the design phase has served as baseline data.