Laserfiche WebLink
Bioretention Area' Maintenance Plan for <br />Stanford in Redwood City — Phase 1 <br />March, 2017 <br />Bioretention areas function as soil and plant -based <br />filtration devices that remove pollutants through a <br />varietv ofphysical, biological, and chemical treatment <br />Processes. These facilities normally consist of a grass <br />buffer strip, sand bed, ponding area, organic layer or <br />mulch layer, planting soil, andplants. <br />Project Address and Cross Streets <br />Multiple <br />Assessor's Parcel No.: Multiple <br />Property Owner: Leland Stanford Junior Universitv <br />Phone No.: (650) 723-9611 <br />Designated Contact: Annette Walton <br />Phone No.: (650) 724-4945 <br />Mailing Address: 3160 Porter Drive. Suite 200. Palo <br />Alto. CA 94304-8442 <br />The property contains 28 bioretention areas, located as described below and as shown on Exhibit `B". <br />I. Routine Maintenance Activities <br />The principal maintenance objective is to prevent sediment buildup and clogging, which reduces <br />pollutant removal efficiency and may lead to bioretention area failure. Routine maintenance activities, <br />and the frequency at which they will be conducted, are shown in Table 1. <br />Table I <br />Routine Maintenance Activities for Bioretention Areas <br />No. Maintenance Task Frequency of Task <br />I Remove obstructions, debris and trash from bioretention area <br />Monthly, or as needed after storm events <br />and dispose of properly. <br />2 Inspect bioretention area to ensure that it drains between storms <br />Monthly, or as needed after storm events <br />and within five days after rainfall. <br />3 Inspect inlets for channels, soil exposure or other evidence of <br />Monthly, or as needed after storm events <br />erosion. Clear obstmctions and remove sediment. <br />4 Remove and replace all dead and diseased vegetation. <br />Twice a year <br />5 Maintain vegetation and the irrigation system. Prune and weed <br />Before wet season begins, or as needed <br />to keep bioretention area neat and orderly in appearance. <br />6 Check that mulch is at appropriate depth (3 inches per soil <br />Monthly <br />specifications) and replenish as necessary before wet season <br />begins. <br />7 Inspect bioretention area using the attached inspection checklist. <br />Monthly, or after large storm events, and <br />after removal of accumulated debris or <br />material <br />II. Prohibitions <br />r Bioretention areas include linear treatment measures designed to filter water through biotreatment soils. A bioretention area <br />that has no waterproof liner beneath it and has a raised underdrain in the underlying rock layer to promote infiltration, as <br />shown in Section 6.1 of the C.3 Technical Guidance, may also be called a "bioinfiltration area". <br />Page 6 Stanford in Redwood City - Phase 1 <br />ATTY/AGR/2017.072/STANFORD - STMMA <br />REV: 04-05-17 PR <br />