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Table 16: Dams on Size 2, 3,4 Rivers by TypeEDU Dams on Size 2, 3, 4 Rivers Summary: Percentage of Dams by Type CategoriesEDUTotal #dams% HYDROELECTRIC% FLOODCONTROL%WATERSUPPLY%RECREATION %IRRIGATION%OTHERSaco 223 55 14 4 18 0 8Lower CT 201 29 7 23 21 0 19Middle CT 81 63 6 5 21 1 4Cape 5 20 0 0 20 60 0Upper CT 47 62 9 2 13 0 15Total % 47 10 11 19 1 12Total # dams 557 263 56 61 107 4 66Expert Interviews452 expert interview site records were recorded as of 12/10/02. This represented interviews fromover 85 individual experts. The sites were distributed as follows, 207 sites from Massachusetts,95 sites from Connecticut, 21 sites from Rhode Island, and 129 sites from New Hampshire.Expert interviews were not conducted in VT because their recently completed VermontBiodiversity Project provided the expert information needed. Expert interviews were also notcompleted for the coastal sections of Maine due to the desire of the Maine Chapter to gatherexpert interviews on these areas in late spring 2003.Condition: Discussion and ConclusionThe overall landscape context non-system relative analysis highlighted the trend within theanalysis area for the more northern and non-coastal areas to have better Landscape Contextranks. Over 80% of all watersheds in the Cape Cod EDU and Lower Connecticut EDU fell intothe two most impacted categories, reflecting the high levels of urbanization and agriculturewithin these southerly and coastal EDUs. The Upper Connecticut EDU had the highestpercentage of watersheds in the least impacted category 1 (15%) followed by the MiddleConnecticut (5%) and Saco-Merrimack-Charles EDU (2%). Using the category where thehighest percentage of watersheds in an EDU fell as a measure of the EDU’s dominant condition,the Upper Connecticut EDU was predominantly good, the Middle Connecticut was moderate,Saco-Merrimack-Charles EDU was fair-poor, the Lower Connecticut was fair-poor, and CapeCod was fair-poor.In terms of the Landscape Context percent developed component, the Upper Connecticut EDUhad the highest percentage of watersheds in the least impacted category 1 (55%), followed bySaco-Merrimack-Charles EDU (20%). The Cape Cod EDU had the highest percentage ofwatersheds in the most impacted category 5 (40%), followed by the Lower Connecticut EDU(31%). Numerous studies have found a negative relationship between the amount of catchmenturban area and stream reach level aquatic Index of Biotic Integrity (IBI) scores (Jones and Clark1987, Steedman 1988, Couch et al. 1997, Dreher 1997, Wang et al.,1997, Yoder et al. 1999,Gordon and Majumder 2000). Impervious surfaces associated with development are widely citedas major sources of non-point pollution such as sedimentation and alteration of the flow regimeas water rapidly runs off relatively impervious surfaces, especially in storm or snowmelt events.The increased silt and sediment load increases turbidity in streams, alters nutrient levels andchemistry of water, reduces the quality of gravel spawning beds, and can change the distributionand distinction between riffle, pool, and run habitat. These changes have been linked tosignificant changes in the diversity and abundance of species (Berkman, and Rabeni 1987).REVISED 6/2003AQUA-RESULTS-32