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HomeMy WebLinkAboutCC - Storm Water Report CENTURION ENGINEERS, INC. Prepared By: Property Location: Centurion Engineers, Inc 2055 South Locust Grove Road 2323 S.Vista Ave Ste 206 Meridian, ID 83642 Boise, ID 83705 www.centengr.com STORM WATER SYSTEM, SYSTEM OPERATION AND MAINTENANCE REPORT FOR 2055 SOUTH LOCUST GROVE ROAD MERIDIAN. ID 83642 Date: September 13, 2023 ITUR-'to A Prepared by: -� 4 7457 Matt Reinhart, P.E. 113/23�Q Centurion Engineers, Inc. f � F mareinhart@centener.com 208.343.3381^ Page 1 of 14 Centurion Engineers, Inc . Table of Contents Title Page Tableof Contents....................................................................................................................................................................2 1.0 Manual Purpose.................................................................................................................................................................3 2.0 Facility Location and Description.....................................................................................................................................3 3.0 Landowner's& Operator's Responsibilities......................................................................................................................3 3.7 Retention of Inspection Records.......................................................................................................................................3 3.2 Subsurface Disposal Systems—Seepage Beds.................................................................................................................3 4.0 Safety Information............................................................................................................................................................4 4.7 Inspections........................................................................................................................................................................4 4.2 Maintenance......................................................................................................................................................................4 4.3 Maintenance Schedule......................................................................................................................................................5 4.4 Component Failure............................................................................................................................................................5 5.0 Best Management Practices.............................................................................................................................................6 5.0 Facility Maps of New Project............................................................................................................................................7 7.0 Maintenance and Inspection Forms.................................................................................................................................9 Page 2 of 14 Centurion Engineers, Inc . 1.0 Manual Purpose This manual outlines the maintenance duties to be performed by the Landowner and or the Operator/ Manager Nine Mile Creek Bungalows located at 2055 South Locust Grove Road, Meridian, ID 83642. The goal is to preserve the integrity and successful operation of the new storm drainage system for the project. 2.0 Facility Location and Description The project is to create a four-lot residential subdivision with a common driveway.The project will retain stormwater onsite. The storm drain system is comprised of one seepage bed. Storm water runoff from the site surface flows to one sediment tank with asphalt driveway around it.The sediment tank is located in the paved centrally located common driveway. The project site is relatively flat generally grades from the east to the west.The storm water will be directed to one sediment tank.The stormwater will be directed through the sediment tank into a seepage bed. 3.0 Landowner's & Operator's Responsibilities It is the responsibility of the landownerto perform,or cause to be performed,all maintenance on all storm drainage facilities located on the property. (Refer to Sections 2.0,4.2 and 7.0.) The land/owner, operator/manager is required to provide access to the city of Meridian for inspections and review of operation and maintenance activities/records. 3.7 Retention of Inspection Records Keep all records of inspections performed on the entire drainage system for a period of at least five (5) years. 3.2 Subsurface Disposal Systems—Seepage Beds The catch basins, pipes and sediment tanks must be inspected periodically and after substantial rain events for trash and debris. All debris shall be removed and disposed of properly. All paved areas must be kept free of dirt and sediment to minimize impacts to the seepage beds. Accumulated oils and grease and sediment must be removed from the catch basins and sediment tanks on at least an annual schedule. Volumes of onerous materials within the basin should be observed and checked by a qualified person. Frequency of cleaning accumulations from the basin/tank may vary depending on the site, and uses occurring on it, but it is very important to have them checked and properly maintained for system longevity. Catch basins, pipes and sediment tanks may be cleaned by contracting with a septic pumping service to pump out and dispose of sediment that collects. Material removed from the basins/tanks is considered hazardous and should only be removed and disposed of by a qualified person. Additionally, there are monitoring wells located near and/or in the seepage bed. These monitoring wells may be used to observe the presence of any ponding water. Should water be present in the any monitoring wells for a period of time exceeding forty-eight(48) hours after a rain storm event,the ponding may be an indication of slowing infiltration rates and possible failure of the seepage bed system. In this case, a qualified maintenance company must be retained to assess the situation and conditions and recommend any correction effort necessary. Spills in the access drives areas,particularly of gasoline and oils,must be contained immediately. It is suggested that readily available cat litter be used to spread on the spill to allow for containment followed by proper clean-up. IF WASTE MATERIALS WITHIN SEDIMENT TANKS OR BASINS IS NOT REMOVED IN A TIMELY MATTER AND ON A REGULAR BASIS AND IS ALLOWED TO ENTER THE SEEPAGE PIT,THE SYSTEMS WILL FAIL. REPLACING THE SYSTEMS IS EXPENSIVE AND MAY BE AVOIDED BY QUALITY MAINTENANCE. Page 3 of 14 Centurion Engineers, Inc . 4.0 Safety Information 4.7 Inspections The inspector should have the proper safety equipment(heavy-duty gloves,steel-toed boots,first aid kits,for example) and training before conducting any inspections. If the storm water system inspection reveals a safety problem, it may be necessary to modify the site activities to reduce or eliminate the safety risk.The following is a list of safety precautions an inspector should be aware of when conducting storm water system inspections. • Never enter a confined space unless the individual has had proper Occupational Health and Safety Administration (OSHA) training. Do not enter any confined space until the atmosphere has been checked and proper safety equipment is worn or erected. • Avoid entering pipes or conduits without another individual present. If the structural strength of a pipe or conduit is questionable, do not enter the pipe or conduit. • Check the ventilation in the storm water system before using any ignitable materials. Storm water systems may be sealed and have poor ventilation, posing a safety risk to the inspector if the vapor comes in contact with an open flame. Also be sure to allow the storm water system to vent for a period of time if a peculiar odor is present. • Wear gloves if any mechanical parts or structure components are going to be handled.Wearing gloves not only reduces the risk of getting cuts and abrasions, but also reduces the exposure of pollutants to the skin. • Lift manhole covers or other structural covers (trash racks,access covers,etc.) carefully.These items can be very heavy and if wet, can be slippery.Also, learn the correct way to lift heavy items to avoid back injury. • Be aware that nails, broken glass or other sharp debris may be in the storm water system and can cause injury. Wearing the proper safety clothing will reduce the safety risk associated with these objects. • All maintenance and inspection records must be kept and maintained for a period of not less than five (5) years. 4.2 Maintenance All maintenance work should be done in accordance with OSHA regulations. Maintenance personnel will have the proper safety equipment (heavy-duty gloves, steel-toed boots, first aid kits, for example) and training before performing any maintenance on a storm water system.The following is a list of safety precautions maintenance personnel should be aware of when they perform maintenance on storm water systems. • Operate equipment safely and in accordance with manufacturer specifications. Equipment operators should be aware of site personnel at all times to avoid causing injury to others. • Contact utility companies before excavating at the site. Underground utility wires may be present. Cover or clearly mark excavated areas that cannot be filled in at the end of the day to alert people of the potential risk.Also, be aware of overhead electrical wires that could come in contact with maintenance equipment. • Identify where you will dispose of removed sediment or wastes prior to cleaning the storm water system. Use shovels,trowels or a high-suction vacuum to remove wastes. Do not clean out sediment or waste with bare hands. The sediment or waste may be hazardous. Place the sediment or waste in an area where it cannot be washed into a storm drain or water body. • Wear gloves if any mechanical parts or structural components are going to be handled.Wearing gloves not only reduces the risk of getting cuts and abrasions, but also reduces the exposure of pollutants to the skin. • DO NOT WASH OIL, GAS OR ANY OTHER SPILLS INTO THE STORM DRAIN SYSTEM. Do NOT come into direct contact with wastewater within the system.Do not enter any confined area where waste is present. Decaying waste produces deadly gases that can be fatal. Page 4 of 14 Centurion Engineers, Inc . 4.3 Maintenance Schedule Weekly Intervals and After a Rainfall Event 1. Perform a visual check of the access drive and common area. Remove and dispose of trash and litter. Every Three Months 1. Observe the appearance of the fluid in catch basins. If excessive solids and accumulations of surface oils are present in it, it is time to have it pumped. Every Year 1. Have the catch basins and sediment tanks pumped and cleaned. Perhaps pumping may be required more or less often depending on use.After several years, a trend for cleaning should become apparent. 2. Review the general condition of the catch basin, sediment tanks and their accesses. Make any repairs necessary. 3. Open and observe any standing water in the monitoring wells. Ponding water for periods in excess of forty-eight hours is an indicator of possible infiltration failure. 48 Hours After a Notable Rainfall Event 1. Open seepage bed monitoring wells and observe for ponding water. If present, a qualified maintenance company must be retained to assess the situation and conditions and recommend any correction effort necessary. 4.4 Component Failure The various components that comprise the drainage system may fail if necessary, maintenance is not performed or simply due to system age. Failure is defined as the system not being able to treat and dispose of run-off in the manner intended by the design. Component failure is most notably evident by the system not infiltrating all run-off water within 48 hours. The reader is directed to the various maintenance and inspection forms contained within this manual in Section 7.0. Each system component has a sheet to diagnose problems observed and recommendations for correction. Should the corrections suggested not resolve the observed problem,the system may be in failure. In that case,contact the Meridian City Community Development forfurther information and recommendations for failure correction. Page 5 of 14 Centurion Engineers, Inc . 5.0 Best Management Practices The following BMPs are intended to keep pollutants out of the storm water runoff at the site.These BMPs are also known as source controls and were selected from the Idaho Catalog of Storm Water Best Management Practices. Ensuring the source controls are followed is the responsibility of the maintenance supervisor.These include the following: • The parking lot is to be kept clean and free of trash and debris.This is particularly true in the area of the trash enclosure and fuel islands. • Should a fuel or grease spill occur, do not wash or rinse the material into the storm drainage system.This could foul the drainage system. Place clay absorbent material, such as diatomaceous earth or cat litter on the spill area. Let the material be absorbed and then sweep the material up for proper disposal. • Drop cloths will be used when performing maintenance work,such as painting,scraping,or sand blasting.The collected, material will be disposed of daily. • For site maintenance,sand bags,filter fabric or rock dams will be used to cover the catch basins. Material such as dust, grit, paint chips or grease or dirt must not be deposited on the parking lot near storm drains. • All drop inlets have been stencilled with. a"DO NOT DUMP WASTE"message. Page 6 of 14 Cent ur io n Eng ineer s, Inc . 6.0 Facility Maps of New Project 9"�3�2p'�€ �a,yy,_ 'aru wooer Sao xmvnn eo uo�mown a�®_xm wmn8uw�'nwx I lOEE'EbE802 y 3u o a3t0m0 imunob 3w x vows mm e0 verve v 00 !o0190a'nE'..7"z0202 n:ie v�MNIDN3 wo�E 2wyom L84L'"� smopsmq IT..D a1ry,I amNxuns 'ONI'S7133NIDN3 NOItlNN37 ,� 4�L8tI1M� �e Pu]P�taa45 altil .5,.-d .52 € O ao M, o 0 fflnii NH o R. It Ril Ill's I- ere� IN IN � #r-4 Ili I [gill b. � €.,b� @t . d tl xb Z �.€ "6 a 5- b e €1 eel gO € z€€€ — '€ g € q €��a :ga€ C A� ��4�&: Jill, a is g sgx= 6 ¢ � �gg� it sJ Z ® s I 5 IN i g ���- �b W 9 Nil 5iF "8 pp be 8 S i'E HOW M lilt IN I r a Nils � ®� s Page 7 of 14 Cent ur io n Eng ineer s, Inc . .33N/OM m�auawz.rwliaereceeoz � � Y��dO� 3 ��ne��imums%'0xou a�ia�nw�sumn urea sP�e of"✓Roe 9az ws�a nxn s azaz ueld LMaune Puel Yiaau�8w 8uPlnsuaJ LSbL�'� sMo 2-a 310-o alryl-IN 21 'DWI•SH33NIDN3 NOINIUN33 HO�801N�° �ei� si?elaQ a5e?eyi uuoyS�8 uo�lauzsm, �uaN ON IG -—-—-—-—-— o B `E ;•<:�� fig$ _� �E ��gi � g pp s Jim iIs 0 �s w 1 H Page 8 of 14 Centurion Engineers, Inc . 7.0 Maintenance and Inspection Forms Inspection Cover Sheet Date: Facility Name: Facility Address: Facility Owner: Inspector Name: Inspector Phone Number: Important Safety Information • Never enter a confined space or trench unless you have proper Occupational Health and Safety (OSHA) training. Do not enter any confined space unless the atmosphere has been checked and proper safety equipment is worn or erected. • Check the ventilation in the storm water system before using ignitable materials.Some storm water systems have poor ventilation and can pose a safety risk to the inspector if the vapour comes in contact with an open flame • Always cover or clearly mark excavated areas as potential safety risks if the areas cannot be filled in by the end of the workday. Inspection Comments: Page 9 of 14 Centurion Engineers, Inc . Maintenance Report Form Date: Facility Name: Facility Address: Name of Person Overseeing Maintenance: Type of System: Date of Last Inspection: Describe maintenance activities, including type of work, completion dates, contractors,time needed to complete task, and cost. Page 10 of 14 Centurion Engineers, Inc . CIM-1 Minimizing Directly Connected Impervious Areas (DCIAs) Storm water system Are any of these conditions problem Recommendation feature present Sediment accumulation Sediment build-up Remove sediment carefully to avoid exceeds 2"in depth on vegetation damaging the existing vegetation. Dispose of sediment properly. Mow vegetation regularly.Grass should be mowed to a height of 4-9"for best storm water treatment. Grass becomes excessively Tall grass or Remove weeds,if necessary.Call the tall or weeds invade the area weeds University of Idaho Cooperative Extension System for information on eradicating weeds in storm water Landscaped or natural area systems. Trash and debris are present Trash and debris Remove waste and dispose of properly. accumulation Remove substance and eliminate its Offensive color,odor,or Unknown or source. If you are unsure whether the sludge is present uncharacteristic substance is hazardous,take a sample substance or contact a qualified hazardous waste consultant for assistance. Re-grade and re-seed area to eliminate Erosion or scouring is evident Excessive flows or high velocity or channelized flows.Over- flow channelization seed areas where bare spots are present. Page 11 of 14 Centurion Engineers, Inc . OM-2 Infiltration Storm water Are any of these Problem Recommendation system feature conditions present Excavate infiltration system and remove any excess sediment. Dispose of sediment Standing water is present 24 Sediment build-up properly.An engineer or geotechnical hours after storm event on bottoms or sides consultant should examine drain rock and filter of infiltration system fabric to determine if replacement is needed. Re-install infiltration system 12"into free draining material. Review options for managing storm water as described in the latest revision of Sections 8000 and 8200 of the ACHD Policy Infiltration system Manual. Infiltration may not be allowed. incorrectly designed Contact Meridian City Community Standing water is present 24 or sited(high Development Department for more hours after storm event ground water area) information. Infiltration system Excavate infiltration system and re-install General incorrectly infiltration system 12"into free draining constructed material. If good free draining material is not accessible, contact the design engineer to see if a more appropriate drainage system can be installed. Unknown or Remove substance and eliminate its source. If Offensive color,odor,or sludge is uncharacteristic you do not know if the substance is hazardous, present substance take a sample or contact a qualified hazardous waste consultant for more information. Propane,oil,or gasoline odor or Accumulation of Contact a qualified hazardous waste puddle is present petroleum products consultant for information on proper treatment and disposal of petroleum products. Pre-treatment Clean out accumulated debris in pre-treatment system not working system and dispose of properly. Excessive debris,sediment,and Install a pre-treatment system upgradient from oil build-up is present. properly the infiltration system.The pre-treatment Pre-treatment system should be approved Meridian City system not installed Community Development Department. Inlet/outlet pipes Standing water is present 24 Clogged pipes Clean out sediment and debris from pipes. hours after storm event See OM-10, Pipes,for more information. Page 12 of 14 Centurion Engineers, Inc . OM-6 Sand Filters Storm water Are any of these � Problem Recommendation system feature conditions present Dumped yard wastes or non-degradable materials Accumulation of Remove trash and debris and dispose of properly. (glass,plastic, Styrofoam, trash and debris etc.)are present in pond Offensive color,odor,or Unknown or Remove substance and eliminate its source. If you do not know if the sludge is present uncharacteristic substance is hazardous,take a sample or contact a qualified substance hazardous waste consultant for more information. Propane,oil,or gasoline Accumulation of odor or surface film is petroleum products Contact a qualified hazardous waste consultant for information. resent Sediment accumulation Sediment build-up Remove sediment so that no deposits remain on the grass layer of General exceeds''/z'in depth on grass layer(if the sand filter. Dispose of sediment properly. applicable) Concentrated water flow Clogged or Clean or repair weir so that water flow is uniform across the sand occurs over the sand filter damaged weir filter. Grass taller than 6";weeds Overgrown Mow grass regularly.Seek advice from the University of Idaho begin to invade the filter vegetation or Cooperative Extension System(Ada County)or the Idaho Dept.of nuisance weeds Agriculture regarding appropriate methods for controlling weeds. Standing water around Clogged or Repair or replace parts as needed. sand filter is present damaged pipes Bare soil beneath the rock Rock pad is missing Replace or rebuild the rock pad to design specifications. is visible or out of place Slope has areas where Eliminate causes of erosion,if possible. If it isn't possible,use erosion is at least 2"deep erosion and sedimentation control best management practices and there is a potential for Soil erosion (BMPs)listed in the Idaho Catalog of Storm Water Best future erosion Management Practices. Water drawdown though sand filter takes longer than Replace the top 6"-12"of sand media. Use a flat shovel to remove Sand filter media 24 hours;water flow Clogged sand filter the sand.May require replacement of entire sand filter section.OR bypasses sand filter;or, media Replace sand filter media so that the flow and percolation of water concentrated water flow though and across the sand filter is uniform. occurs over the sand filter Sediment accumulation Vector or shovel out sediment deposits on sand filter. Dispose of exceeds /z"in depth on Excessive sediment sediment properly. sand media section Below ground vault Sediment accumulation Vector or shovel out sediment deposits in the first chamber of the (if applicable) P p properly. exceeds 6"in depth in vault Excessive sediment vault and dispose of Yard wastes or non- degradable materials Accumulation of Remove trash and debris from vault and inlet/outlet piping. Dispose (glass,plastic, Styrofoam, trash and debris of wastes properly. etc. are present in the vault Inlet/outlet pipe Drain pipes become Vector or shovel out sediment or debris.You can also use a high clogged with sediment or Excessive sediment pressure hose to clean out sediment or debris.See OM-10, Pipes, debris for more information. Pipe is damaged, broken, Defective pipe See OM-10, Pipes,for more information. Under drain pipe cracked,or corroded Sediment accumulation Excessive sediment Remove sediment from pipe and dispose of properly. Repair or impedes water flow replace pi e to design specifications. Debris covers at least 25% Trash rack of the bar screen oor bar Trash rack is Replace screen,if necessary. Remove trash and debris and screen is missingplugged or missing dispose of waste properly. Page 13 of 14 Centurion Engineers, Inc . OM-7 Oil/Water Separator Storm water Are any of these Problem Recommendation system feature conditions present Excessive Check if separator has excess sediment or oil sediment or oil accumulation. If so, remove oil or sediment accumulation and dispose of properly. Discharged water is discoloured, Damaged baffle Check baffle integrity. If damaged,repair or turbid,or has and oil sheen replace to design specifications Contact the design engineer to check if the Incorrectly system is appropriately sized for the drainage designed basin. If it isn't,the upgrade the system with and additional or larger separator. Sediment accumulation exceeds 1" Excessive Vector or shovel out sediment. Dispose of in the bottom of vault sediment sediment properly. Standing water is present 24 hours Sediment build-up Vector or shovel out sediment. Dispose of after storm event blocks flow sediment properly. Conventional gravity through separator separator Yard wastes or non-degradable Accumulation of Remove trash and debris from vault and materials(glass,plastic, Styrofoam, trash and debris inlet/outlet piping.Dispose of wastes ect.)are present in the vault pro erl . Oil accumulation exceeds 1"at Excessive oil Vector or manually remove oil from water water surface accumulation surface. Dispose of waste properly. Pipes broken or damaged;cracks in Damaged Repair or replace to original design pipe are wider than'/4"at the joint inlet/outlet pipe specifications. Cover cannot be opened;cover is Defective access Repair or replace to original design corroded or damaged cover specifications. Cracks in vault are wider than''/2"; Structural damage Replace or rebuild the vault to design soil enters the vault through the to vault specifications. cracks Baffle is cracked,warped,or Defective baffles Repair or replace baffles to original design corroded specifications. Excessive Check if separator has excess sediment or oil Discharged water is discoloured, sediment or oil accumulation. If so, remove oil or sediment turbid,or has and oil sheen accumulation and dispose of properly. Damaged Check coalescing plate integrity. If damaged, coalescing plate repair or replace to design specifications. Sediment accumulation exceeds 1" Excessive Vector or shovel out sediment deposits on the in depth in vault sediment vault bottom. Dispose of sediment properly. Yard wastes or non-degradable Accumulation of Remove trash and debris from vault and materials(glass,plastic, Styrofoam, trash and debris inlet/outlet piping.Dispose of wastes etc.)are present in the vault properly. Coalescing plate Oil accumulation exceeds 1"at Excessive oil Vector or manually remove oil from water separator water surface accumulation surface. Dispose of waste properly. Pipes broken or damaged;cracks in Damaged Repair or replace to original design pipe are wider than'/4"at the joint inlet/outlet pipe specifications. Standing water is present 24 hours Sediment build-up Vector or shovel out sediment. Dispose of after storm event blocks flow sediment properly. through separator Baffle is cracked,warped,or Defective baffles Repair or replace baffles to original design corroded specifications. Cracks in vault are wider than Structural damage Replace or rebuild the vault to design /2";soil enters the vault through to vault specifications. the cracks Page 14 of 14