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It i~ recommended that a 54-inch Rep with headwall and 66 inchcs of headwater be placed across Eaton Avenue on the west side of Second Street 10 intercept flow in the channel between Golden Avenue and Eaton Avenue. Also a 36-inch Rep culvert with 4-foot of headwater should be placed , diagonally across Eatlln Avenue and Second Street to intercept flow at the northeast side of the intersection and convey it tuthe southwest corner of the intersection. 11. 8, M previously indicated,the existing channel on the west side of See ondStreet between Golden Avenue aod Eaton Avenue is poorly developed and in very poor condition. This channel should be riprap lined and constructed with a 2-foOl bottom width and flow depth of approximately 3 feet as indicated on Figure 4 in Appendix A. Approximately 300 feet of this channel lining i~ required. 9, Existing structure no. 28 (24.inch CMP with 24 inches of headwater) is severely undersized to adequately convey flow from the lO-year design ~torm. This structure is located on the west side of Second Street and erosse~ Carr Avenue. Thi~ culvert is also in a location, as previously descrihed above, which has severe consequences on the flooding which occurs in the downtown district. A review of the existing drainage facilities along Second Street between Eaton Avenue and Bennett Avenue led tn the recommendation that an out[alllinc be cunstrueted in Second Street between Eatnn Avenue and Hennett Avenue. This outfall line will convey flow intercepted from the open chaflflel at Eaton Avenue undergroufld to the storm sewer system at Bennett AvenL1e. It is recommended that the outfall line be 42-inch Rep installed at a slope of approximately 5%. In addition, small swales shall be con,tructed on each side of Second Street between Eatoll Avenue and BellJ1elt Avo::nuo::. Inlets sl10uld be in,tallcd in thcse sWllles at Carr Avenue, one on eachsidcof Second Street. 600 lineal feet of 42-inch RCP outfall will be required. 12, VI-9 , 10, Existing structure nu. 95 (16-inch CMP with 24 inches of headwater) is inadequate to convey runoff from the lQ-year design storm. It IS recommended that this culvert be replaced with a 24-inch CMP with 30 inches of headwater, Existing structure no. 67,68 and 36 were originally intended to convey runoff from the westerly portion of the Second Street Tributary around the courthouse and into the Bennett Avenue storm ~ewer system. The~e facilities are in very poor condition, all outlets cannot be located and di~cussions with local resident~ indicate that they may not function at all. It is recommended that these cxisting structures be replaced as follows: A new inlet should be installed in the area of the inlet to existing structure no. 67. This inlet should be sized to intercept all overlnt flow which reaches it. From this inlet a new 36-ineh RCP storm sewer should be installed which runs north of the courthouse to Fir~t Street then south to Bennett Avenue. At the interscction of Fitst Street and Benncll Avenue, this pipc will be connected to the new Bennett Avenue storm sewer system. Approximately 300 lineal feet of 36-inch RCPis required. The cxisting Bennett Avenue storm sewer system between First Street and Third Street consists primarily of small grated inlets with small (less than 24.inch eMP) storm sewer piping. Discussions with city staff indicate that the storm scwer piping has sevcrely deteriorated. Also. inlet capacity appears inadequate even though large amuunts ofputential runoff will be int erceplcd hy the recommendcd upstream improvements. In addition, existing inlet locations do not appear suitable when the fulure Bennett Avenue streetscape projectts undertaken. 'Ine ioilowing improvements to the Bennen Avenue storm sewer system within the SecoOll Street Tributary arc rccommended: VI.lU