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sticks. Unless protective measures are taken, this process of "succession" <br />will continue; eventually the ponds will become swampy bogs, then grassy <br />meadows, then scrub forests. Succession occurs very slowly, but it is inev- <br />itable without intervention and increased water flow. <br />Water flows from the pc west of Coodpasture Island Road into the pond <br />just north o the jobile home park. It then flows east under Delta Highway, <br />north through Debrick Slough and back under. the highway to connect to the <br />lower pond system (see map 2). During periods of high water, flow is diverted <br />into the lower'ponds by percolation and overspills located between Goodpasture <br />Island Road and Delta "Highway. The locations and sizes of the culverts serving <br />the Delta Ponds are c to satisfactorily routing the water supply to the <br />ponds. Equally inpor - are the dikes which separate the upper and lower <br />ponds. Because the el_va�io <br />n of the lower ponds is approximately three feet � <br />below that of the upper ponds, any breeching of the dikes would have serious <br />consequences for pond levels and water flow direction. <br />Overall, the network of culverts and dikes appears adequate, with proper <br />maintenance, to serve as the basic frame for the development of Delta Ponds as <br />a public park, although the results of further technical study might.indicate <br />the need for minor engineering adjustments. .Of most immediate concern is the <br />need for aft increase in water supply, especially during the critical summer <br />and early autumn periods of low flow in the Willamette River. During these <br />periods, the water level of the river is below that of the ponds, thus depriv- <br />ing the ponds of necessary flow. <br />Finally, it should be kept in mind that Delta Ponds is part of an old <br />river channel, and during the 1964 flood, considerable water flowed through <br />this corridor. Since 1964, the capacity of the Willamette River has decreased <br />between the Ferry Street Bride and the Beltline Bridge due to, among other <br />factors, a decrease in gravel extraction in the area, migration of gravel and <br />