MCU14/0056 - Attachment H -Economic Needs Assessment

                              CONSTRUCTION                          STRUCTURE (IF ANY), THEN MAKE ALL
                                                                    NECESSARY REPAIRS AND MAINTENANCE                                                                  L = 2.4 m (min)
                              1. REFER TO APPROVED PLANS FOR        TO RESTORE THE DESIRED FLOW
                              LOCATION AND CONSTRUCTION DETAILS.    CONDITIONS.
                                                                                                                                                                    MAKE PIT SAFE BY
                              IF THERE ARE QUESTIONS OR PROBLEMS                                                                   Fabric may need to be
                                                                                                                                                                 FENCING OR OTHER MEANS
                              WITH THE LOCATION, OR METHOD OF       4. CHECK THE STRUCTURE AND                                 placed on the inflow bank
                              INSTALLATION, CONTACT THE ENGINEER    SURROUNDING CHANNEL BANKS FOR          Flow
                                                                                                                              to provide scour protection
                              OR RESPONSIBLE ON-SITE OFFICER FOR    DAMAGE FROM OVERTOPPING FLOWS
                              ASSISTANCE.                           AND MAKE REPAIRS AS NECESSARY.
                                                                                                                                                                         0.6 m (min)
                              2. CLEAR THE FOUNDATION AREA OF THE   5. REMOVE SEDIMENT AND RESTORE                                                                      1.0 m (max)
                              OUTLET STRUCTURE (IF ANY), AND        ORIGINAL SEDIMENT STORAGE VOLUME                                             Excavated
                              INSTALL AS PER SEPARATE               WHEN COLLECTED SEDIMENT EXCEEDS                                              sediment trap
                              INSTRUCTIONS.                         30% OF THE PIT VOLUME.

                              3. EXCAVATE THE SETTLING POND IN      6. DISPOSE OF SEDIMENT AND DEBRIS IN
                              ACCORDANCE WITH THE APPROVED          A MANNER THAT WILL NOT CREATE AN
                                                                                                                    (a) Excavated sediment trap located within a
                              PLANS. UNLESS OTHERWISE SPECIFIED,    EROSION OR POLLUTION HAZARD.                                minor drainage path
                              THE EXCAVATED PIT SHOULD HAVE A
                              SIDE SLOPE OF 2:1(H:V) OR FLATTER.    REMOVAL

                              4. APPROPRIATELY STABILISE ANY BANK   1. WHEN THE UP-SLOPE DRAINAGE AREA
                              SUBJECT TO DIRECT INFLOW.             HAS BEEN STABILISED, REMOVE ALL
                                                                    MATERIALS INCLUDED DEPOSITED                                            L1 = 5D (min)          L2 = 2.4 m or 7D (min)
                              5. ESTABLISH ALL NECESSARY UP-SLOPE   SEDIMENT AND DISPOSE OF IN A                                          ideal: 10D (min)        (whichever is the greater)
                              DRAINAGE CONTROL MEASURES TO          SUITABLE MANNER THAT WILL NOT
                              ENSURE THAT SEDIMENT-LADEN RUNOFF     CAUSE AN EROSION OR POLLUTION
                              IS APPROPRIATELY DIRECTED INTO THE    HAZARD.                                                                                         MAKE PIT SAFE BY
                              SEDIMENT TRAP.                                                                                                                     FENCING OR OTHER MEANS
                                                                                                                  Flow
                                                                    2. ALL WATER AND SEDIMENT SHOULD BE                              D
                              6. TAKE ALL NECESSARY MEASURE TO      REMOVED FROM THE BASIN PRIOR TO
                              MINIMISE THE SAFETY RISK CAUSED BY    THE DAM’S REMOVAL. DISPOSE OF
                              THE STRUCTURE.                        SEDIMENT AND WATER IN A MANNER
                                                                    THAT WILL NOT CREATE AN EROSION OR                                                                 0.6 m (min)
                              MAINTENANCE                           POLLUTION HAZARD.                                                                                  1.0 m (max)
                                                                                                                                                 Excavated
                                                                                                                                                 sediment trap
                              1. CHECK EXCAVATED SEDIMENT TRAPS     3. BRING THE DISTURBED AREA TO A
                              AFTER EACH RUNOFF EVENT AND MAKE      PROPER GRADE, THEN SMOOTH,
                              REPAIRS IMMEDIATELY.                  COMPACT AND STABILISE AND/OR           Where space is not available, make optimum use of the available space
                                                                    REVEGETATE AS REQUIRED.
                              2. INSPECT THE BANKS FOR SLUMPING
Catchments & Creeks Pty Ltd




                              OR EXCESSIVE SCOUR.
                                                                                                              (b) Excavated sediment trap located downstream
                                                                                                                           of a stormwater outlet
                              3. IF FLOW THROUGH THE STRUCTURE IS
                              REDUCED TO AN UNACCEPTABLE LEVEL                                                           Drawn:          Date:
                              DUE TO BLOCKAGE OF THE OUTLET
                                                                                                                           GMW            Apr-10 Excavated Sediment Trap                       EST-01