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stormwater outfall formerly functioned as a combined sewer outfall (CSO) and thus is designated CSO#6. The St. Joseph River is approximately 250 feet wide in the project area. 1.3 Leeper Park Island is adjacent to Riverside Drive, between Michigan Street (Indiana Route 3) 1) and East Bartlett Street. The island is owned by the City of South Bend and is part of Leeper Park. The park is maintained as lawn n with many mature trees and a variety of shrubs. Two public water supply wells on the island provide drinking water for the City of South Bend. A stone wall approximately 5 feet high and 1,400 feet long surrounds the island providing some erosion protection. The stone wall includes staircases that descend from the park lawn down to the river. Erosion along the eastern island shore, which extends approximately 720 feet, has undermined the wall. This undermining has resulted in the destruction of three sections of wall' (in two locations) totaling about 250 feet in length. Loss of the wall in these locations has resulted in severe soil erosion farther upland. 1.4 The North Shore Drive site extends approximately 1,500 feet beginning about 600 feet downstream (northwest) of Lafayette Boulevard and ending about 200 feet downstream of PaIkovash Avenue. The riverbank along North Shore Drive is privately owned in association with adjacent residential properties. The bank in this reach is steep, approaching 1 vertical on l horizontal (45°) in some locations. Approximately 51 large trees (greater then 6" stem diameter) are growing along this riverbank. Many of these trees along the lower bank are subject to erosion and undermining. Some areas of the bank, barren of trees, are covered with broken concrete rubble from previous bank stabilization efforts. Part of the bank is eroded to the back of the curb along North Shore Drive, which parallels the riverbank along this site. The erosion also jeopardizes two drainage outfalls and several utility lines at this site. 1.5 The CSO site is across the river from the North Shore Drive site at the intersection of Leland Avenue and Riverside Drive. This site is part of Shetterley Park, which is owned by the City of South Bend. The eroding riverbank extends about 100 feet centered around a retired 30 -inch diameter CSO that currently is serving as a stormwater overflow. The riverbank is approximately 35 feet high, slopes up to about lvertical to 2 horizontal (27), and is wooded. Erosion along this reach threatens the entire bank. The outfall already is being undermined. 1.6 Pur_nose and Need for the Proposed Action: The purpose of this project is to provide a suitable means of shore protection against erosion at the three sites to protect public facilities from being undermined and destroyed. This is needed to counteract the effects of high river flow velocities scouring the bank toe during flood events, which in conjunction with the silty sands and sandy silts composing the riverbanks has resulted in significant erosion along the project reaches. r_. .. i. _ r �.__.:._.._.i _._n �_:-. A-- -- :�_ r.t__. •-t_:-.i ._ ... .._. 1.:..._.1 t.... a,.v..,. .J 4'P..... c„tt, ,,� i n wui tai �«iivii Gi u�au Vy �u "vvdu� uiuii8 iiia wCit �iui ui ui� i�tnuu, iti uS U V al uu,u, vui U . rt,.,u isa..: ... t...,. study because it was determined to be caused by surface erosion and therefore is not covered by the Section 14 authority. -2-