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LSA ASSOCIATES. INC. CEQA INITIAL STUDY /MITIGATED NEGATIVE DECLARATION MARCH 2011 PREDA STREET PIPE BRIDGES UPGRADE SAN LEANDRO, CALIFORNIA 9) Surrounding Land Uses and Setting: The project site is located at an existing sewer pipe crossing over San Leandro Creek adjacent to Alder Creek Circle, near Preda Street, in the City of San Leandro (Figures land 2). San Leandro Creek is an east -west trending creek that flows westward from its headwaters above Upper San Leandro Reservoir. San Leandro Creek continues downstream from Upper San Leandro Reservoir to Lake Chabot and through the cities of San Leandro and Oakland before discharging into San Francisco Bay near the Oakland International Airport. The project site consists of two, southwest- trending, eighteen -inch diameter bell -and- spigot ductile iron sewer pipes crossing over San Leandro Creek. Two steel, Pratt-type, through -truss bridges support the pipes. While the bridges are of relatively similar geometry with painted steel plate, angle, and T- section structural members, the bridge to the east (Bridge R) is of riveted construction and the bridge to the west (Bridge W) is of welded construction. Both bridges span 80 feet and are approximately 3.5 feet wide and six feet deep. Based on dates on construction drawings, Bridge R appears to be approximately 71 years old: the age of Bridge W is approximately 36 years old. The ductile iron pipes transport raw sewage southward across the creek, by gravity-flow, to the treatment plant. The pipes consist of 18 - foot long segments connected together at bell- and - spigot joints. The pipes emerge from the bank adjacent to the Union Pacific Railroad tracks, cross the creek on the bridges, and enter the opposite creek bank adjacent to Alder Creek Circle. The pipes pass through the bridge trusses and are supported by angle sections with bent plate "keepers" that prevent the pipes from moving laterally. The reach of San Leandro Creek immediately downstream of the project site consists of a concrete - lined, trapezoidal flood control channel. The creek banks on either end of the bridge are steep and covered in dense vegetation, primarily blackberry (Rubus sp.) and English ivy (Nedra helix). Portions of the ground surface not covered in blackberry support non - native annual grasses such as ripgut brome (Bromus diandrus), barley (Hordeum sp.), and wild oats (Avena fatua); and ruderal (i.e., weedy) forbs such as Italian thistle (Carduus pycnocephalus), cheeseweed ( Malva parviflora), poison hemlock (Conium maculalum), and wild radish (Raphanus saliva). A large, multi- branched arroyo willow (Salix lasiolepis) is present adjacent to the southeast end of the bridges and its canopy extends over most of the southern bank. Several smaller arroyo willows grow within the creek channel, as well. Other tree species observed growing on the creek banks include blue elderberry (Sambucus mexicana) and silver wattle (Acacia dealbata). Arroyo willow and blue elderberry are both native to California. Hydrophytic plant species, plants adapted to aquatic environments, were observed growing within and adjacent to the channel bottom. These species include horsetail (Equisetum sp.), willowherb (Epilobium sp.), smartveed (Polygonum sp.), and bulrush (Scirpus microcarpus). 10) Other Agencies Whose Approval is Required: The City of San Leandro is the lead agency under CEQA with the primary authority for project approval. In addition, the following responsible and trustee agencies may have jurisdiction over some or all of the proposed project: P: \EG10801 \CEQA\Preda FINAL IS- MND.doc (03(28 /I I) 4