The Gorge Dam Pool sediment load record reflects impacts from a variety of sources. The mass of sediment retained each year in the Gorge Dam pool (see Section 4.3) provides an estimate of the variation in the Middle Cuyahoga River sediment load

(Fig. 9). Indirect evidence suggests that the Gorge Dam effectively traps the river’s sediment load. Downstream KPT-330 in vivo of the dam, the channel is sediment-starved and floored by bedrock and boulders. However, between the dam and the Front St. Bridge, the impoundment is deep and wide, allowing for continued mud deposition (Fig. 2 and Fig. 5). In fact, thick mud accumulation has also occurred mid-pool where the water area is less than at the core C4 reach (Fig. 5). The extremely Talazoparib nmr high sediment

load prior to 1928 is interpreted with caution, because the age model was interpolated between the 1928 210Pb age with large error bars and age of dam construction (Fig. 7). However, events at this time may have contributed to increased sediment loads. First, accompanying the construction of the dam were additional large construction projects on the banks of the dam pool to install power plants (Whitman et al., 2010, p. 80). Second, a large flood in 1913 breached the upstream Le Fever Dam (Raub, 1984) and released of some of its impounded sediment (Kasper, 2010 and Peck and Kasper, 2013). The sharp decline in sediment load at 1928 is an artifact of the age model. From the 1940s to the 1960s sediment load increased at the same time the City of Cuyahoga Falls experienced tremendous population growth in the post World War II years (Fig. 9). Visual examination of topographic maps shows growing networks of streets upstream of the impoundment as suburban developments were constructed. This increased development of the watershed could increase the river’s sediment

load (Fig. 9). Since the 1950s, expanding suburbanization is illustrated in the population growth further upstream in Stow Township (Fig. 9). This development corresponds to a general increase in impoundment sediment accumulation O-methylated flavonoid toward the present day (Fig. 9). We interpret the substantial sediment load increases between 2004 and 2008 and again in 2011 as the result of an increase in extreme flow events (Fig. 9). Five of the top ten floods recorded on the 87-year-long Old Portage stream gauge, downstream of the dam, occurred in 2003, 2004, 2005 and twice in 2011 (NOAA, 2012). These extreme flow events are effective at eroding and transporting sediment. The removal of the upstream Munroe Falls Dam in September 2005, allowed its impounded sediment to be eroded and transported downstream (Rumschlag and Peck, 2007). The greatest amount of erosion and transport from the former Munroe Falls impoundment occurred between 2005 and 2008 although the Le Fever Dam impoundment traps much of this sediment (Kasper, 2010 and Peck and Kasper, 2013).