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Silt Push Boat Course Operation and Maintenance (O&M) of Sewer & Storm Water Drainage System including Safety Precautions O&M of Storm Water Drainage System Lecture 1 Module-2 Lecture-1 2/15 1 Lecture Contents 1. Storm Water Drainage System and its Components 2. Current Issues 3. Sediment Deposition 4. Need for O&M 5. Maintenance of Drains Module-2 Lecture-1 3/15 Storm Water Drainage System Receives runoff from “Storm sewer” inlets and conveys the replaced with the runoff to some point term "storm drain" where it is then to differentiate discharged into a It may be a between sanitary channel, water body, . closed-conduit sewers and storm or piped system . Open channel drains Module-2 Lecture-1 4/15 2 Culvert A drainage pipe used to convey a stream through a road or embankment It may carry a stream for a long distance underground to a surface discharge location Short in length and open at both ends and often must withstand substantial traffic loads Module-2 Lecture-1 5/15 Ditch Ditches are constructed to convey water from storm runoff to an adequate outlet. A good ditch is shaped and lined and does not cause flooding, erosion, or sedimentation. Gutter That portion of the roadway section adjacent to the curb which is utilized to convey storm water runoff. Module-2 Lecture-1 6/15 3 Drop Inlet A location where storm water runoff from an open area enters the storm drain system. Drop inlets are usually part of the public drainage system, but can sometimes be considered private. Module-2 Lecture-1 7/15 Catch Basin A structure in the form of a chamber which is provided along with the sewer line to admit clear rain Water free from silt, grit, debris, etc, into the combined sewer Allows rainwater runoff to be safely collected to prevent road and property flooding Module-2 Lecture-1 8/15 4 Critical Issues Encroachment of drains Silting of drains due to constant blockages Stability of drainage cross-sections dislocated and damaged old lining of the drains Module-2 Lecture-1 9/15 Critical Issues Unpleasant odor of dirty water flowing in the drains Absence of comprehensive data on storm-water drainage network Inadequate attention to cleaning of natural drains and clearance of excess floral growth on the drains Free access to dispose wastewater from nearby habitation Module-2 Lecture-1 10/15 5 Sediment Deposition & Related Issues Due to the sediment deposition the problems occurred in the open channel includes: Encourages prolific weed growth Cause flooding of various degrees of magnitude Ponding of water creates breeding grounds for some disease causing agents Silted roadside drains produce ponding on roads Module-2 Lecture-1 11/15 Sediment Deposition & Related Issues In the case of buried or completely covered storm channels, problems occurred are: Silting + Weed Growth + Bushes Release & accumulation of gases (that can be highly corrosive to the channel material) Module-2 Lecture-1 12/15 6 Need for Maintenance Lack of regular maintenance cause the accumulation of the sediment and garbage in the drain Extensive, regular sediment removal is a difficult and expensive process Routine inspection and preventive maintenance are the best ways to prevent blockages and deterioration of drains Module-2 Lecture-1 13/15 O&M of Drainage System Departments should devise maintenance procedures including: . Frequency of inspection . Programme for dredging . Necessary repair works . Documentation for maintenance records Module-2 Lecture-1 14/15 7 Edit the text with your own short phrases. The animation is already done for you; just copy and paste the slide into your existing presentation. Course Operation and Maintenance of Sewer & Storm Water Drainage System Including Safety Practices Module 2 Operation and Maintenance of Storm Water Drainage System Lecture 5 Maintenance of Storm Water Drainage System 2/22 1 Edit the text with Contents your own short phrases. The animation is already done for you; just copy and O & M Plan paste the slide into your existing presentation. Maintenance Activities for Road Drainage BMPs for Storm Water Drainage System BMPs for Dredging Module-2 Lecture-5 3/22 Edit the text with your own short phrases. The animation is already done for you; just copy and paste the slide into your existing presentation. O & M Plan Module-2 Lecture-5 4/22 2 Edit the text with Requirement of O & M Plan your own short phrases. The animation is already done for . Define the Area to be Covered you; just copy and paste the slide into . Identify Problem Areas your existing . Set an Inspection Schedule presentation. Assign Responsibility for Inspection . Define What Categories of Work will be Performed Under this Program . Identify Parties Responsible for Debris Removal . Keep Records . Budget Module-2 Lecture-5 5/22 Edit the text with O & M Plan for Open Drains your own short phrases. The animation is Storm Are any of these conditions Problem Recommendation already done for water present? you; just copy and paste the slide into system your existing presentation. feature General Dumped yard wastes or no degradable materials Accumulation of trash and Remove trash and debris (glass, plastic, Styrofoam, etc.) are present in debris and dispose of properly. pond Undesirable vegetation is invading the pond Nuisance, poisonous, or Seek advice from the Dept. noxious weeds of Agriculture before applying pesticides. Certain pesticides should not be used near waterbodies. Module-2 Lecture-5 6/22 3 Edit the text with O & M Plan for Open Drains your own short phrases. The animation is Storm water Are any of these Problem Recommendation already done for system feature conditions you; just copy and paste the slide into present? your existing presentation. General Grass is taller than Overgrown Mow grass regularly. Grass should be mowed to a height of 10"m vegetation 4-9" for best storm water control. Avoid over-applying fertilizers. Excessive fertilizer application may compound water quality problems. Offensive color, odor, Unknown or Remove substance and eliminate its source. If you don't or sludge is present uncharacteristic know if the substance is hazardous, either take a sample or substances contact a qualified hazardous waste consultant for more information. Excessive mosquito Mosquitos Install predacious bird and bat nesting boxes to control population is present insects Module-2 Lecture-5 7/22 Edit the text with O & M Plan for Open Drains your own short phrases. The animation is Storm Are any of these Problem Recommendation already done for you; just copy and water conditions present? paste the slide into your existing system presentation. feature General Water flows through holes in Rodents Destroy rodents and repair dam or berm. dam or berm; holes are present around pond Large trees interfere with Overgrown Remove trees that interfere with access or maintenance maintenance activities trees activities. Preserve trees that are not a problem Accumulated sediment Excessive Clean out sediment to original shape and depth of the exceeds 10% of the designed sediment pond. Re-seed pond, if necessary, to control erosion. pond depth Module-2 Lecture-5 8/22 4 Edit the text with O & M Plan for Storm Sewers your own short phrases. Storm water Are any of these Problem Recommendation The animation is already done for system feature conditions present? you; just copy and Accumulated sediment or trash Excess accumulation of Clean out sediment and trash paste the slide into General your existing exceeds 20% of the diameter of sediment or trash from pipe. You can use a high presentation. the pipe pressure hose, vacuum suction, Vegetation is impeding water Overgrown vegetation or other appropriate cleaning flow method. Pipe is rusted; protected coating Corroded pipe is damaged Dent in pipe has reduced the Defective pipe pipe diameter by 20%; water Replace or repair pipe to flow is impeded; pipe is broken original design specifications. Water is leaking from pipe Cracked pipe Module-2 Lecture-5 9/22 Edit the text with your own short phrases. The animation is already done for you; just copy and paste the slide into Maintenance Activities for Road Drainage your existing presentation. Module-2 Lecture-5 10/22 5 Edit the text with Drains your own short phrases. The animation is Defect Cause Outcome Remedies already done for you; just copy and Obstruction Vegetation Blockage Cleaning & paste the slide into and Silting growth, loose Clearing; your existing silt and rock; Deepen ditch (de- presentation. silting), and/or Invert Slope is provide new too flat turnouts Defect Cause Outcome Remedies Drain Lining is Poor Erosion; Erosion control Construction; Damaged Damage to (Turfing and Sudden change in lining Wattling); flow direction; Repair lining; Soil Settlement Realign drain Module-2 Lecture-5 11/22 Edit the text with Drains your own short phrases. The animation is Defect Cause Outcome Remedies already done for you; just copy and Erosion control Invert and Invert slope is Soil Erosion paste the slide into Re-grade/realign sides of drain too steep your existing Carriageway drains presentation. are eroded washed away Repair scour protection Line drain slopes Defect Cause Outcome Remedies Drain Cross- Vehicular or Partial Silting Reshape/regrade Section animal traffic; Erosion Ditch Destroyed Cave-in Line the drain Module-2 Lecture-5 12/22 6 Edit the text with Culverts your own short phrases. The animation is Cause already done for you; just copy and Defect 1. Invert slope too flat; paste the slide into Silting or Debris Blocking 2. Culvert constructed too low; your existing 3. Vegetation and floating debris presentation. lodging Outcome Remedies 1. Intended waterway opening will 1. Clearing and cleaning; be reduced; 2. Provision of a debris rack 2. Ponding on upstream side; 3. Road embankment overflow Module-2 Lecture-5 13/22 Edit the text with Culverts your own short phrases.
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