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HomeMy WebLinkAbout008 - Stormwater O&MSTORMWATER OPERATION & MAINTENANCE MANUAL Ursus Major Lot 2A, Block 5 Nelson Meadows Subdivision Bozeman, MT 59718 Prepared For: Lattice Materials 516 E Tamarack Street Bozeman, MT 59715 Prepared By: Cushing Terrell 411 East Main Street, Suite 101 Bozeman, MT 59715 406.922.7111 www.cushingterrell.com Cushing Terrell Project No. URSUS_MAJ March 06, 2026 Updated April 24, 2026 Stormwater Operation & Maintenance Manual Ursus Major Project No. URSUS_MAJ Cushing Terrell i TABLE OF CONTENTS 1.0 INTRODUCTION ................................................................................................................................................ 2 2.0 SYSTEM DESCRIPTION ................................................................................................................................... 2 3.0 STORMWATER TREATMENT ........................................................................................................................ 2 4.0 RESPONSIBLE PARTIES ................................................................................................................................... 2 5.0 WASTE DISPOSAL ............................................................................................................................................ 2 6.0 INSPECTION & MAINTENANCE REQUIREMENTS ................................................................................ 2 6.1 PARKING/PAVEMENT AREAS (bi-annual) .......................................................................................... 2 6.2 LANDSCAPING GROUNDS (monthly) .................................................................................................. 3 6.3 STORMWATER COLLECTION SYSTEM MAINTENANCE ................................................................ 3 6.4 NORTH STORMWATER INFILTRATION SYSTEM MAINTENANCE ............................................. 3 6.5 EAST STORMWATER INFILTRATION SYSTEM MAINTENANCE .................................................. 3 APPENDICES APPENDIX A: STORM FACILITY INSPECTION FORM APPENDIX B: INFILTRATION SYSTEM MAINTENANCE MANUAL APPENDIX C: MAINTENANCE ACKNOWLEDGEMENT Stormwater Operation & Maintenance Manual Ursus Major Project No. URSUS_MAJ Cushing Terrell 2 1.0 INTRODUCTION The Ursus Major facility is located in the Nelson Meadows Subdivision at the northeast corner of Royal Wolf Way and Prince Lane in Bozeman, MT. This property is located at the following legal address: Lot 2A, Block 5, Nelson Meadows Subdivision Southeast ¼, Section 22, Township 1 South, Range 5 East, Gallatin County, Montana Common street address has not yet been determined. 2.0 SYSTEM DESCRIPTION In general, the proposed developed site will incorporate two underground stormwater infiltration facilities along with storm drain collection structures and conveyance piping. See Appendix A drainage facility map. 3.0 STORMWATER TREATMENT Stormwater treatment will occur by first filtering the stormwater through a row of storm chambers specifically designed for stormwater treatment. The stormwater will then infiltrate into the ground. 4.0 RESPONSIBLE PARTIES Lattice Materials is the responsible party as they manage the operational activities on the site. The Owner’s contact information is as follows: Lattice Materials 516 E Tamarack Street Bozeman, MT 59715 5.0 WASTE DISPOSAL All waste removed from the site shall be legally disposed of at an authorized land fill site. 6.0 INSPECTION & MAINTENANCE REQUIREMENTS 6.1 PARKING/PAVEMENT AREAS (bi-annual) Parking area is to be swept twice annually to remove excess sediment. Recommended sweeping should take place once after spring melt and prior to May 1, and once after August 15 and prior to October 15. Parking lot sweeping shall include cleaning of curb chases. An estimated cost for parking / pavement area sweeping and sediment removal is $600 per occurrence or $1,200 per year. Stormwater Operation & Maintenance Manual Ursus Major Project No. URSUS_MAJ Cushing Terrell 3 6.2 LANDSCAPING GROUNDS (monthly) Regular site maintenance should consist of removal of garbage and fallen debris from the parking lot on an as needed basis. Routine site maintenance will prevent debris from entering the storm water system and will improve storm water runoff quality over the long term. An estimated cost for landscaping grounds maintenance $300 per month or $3,600 per year. 6.3 STORMWATER COLLECTION SYSTEM MAINTENANCE Stormwater catch basins / manholes should be maintained with removal of garbage, and sediment from the storm structure sumps on an annual basis. The maintenance for the stormwater catch basin inlets and manholes is approximately $800 per year. When properly maintained, the useful life for these structures is 100 years and the replacement cost in today’s dollar is approximately $5,000. 6.4 NORTH STORMWATER INFILTRATION SYSTEM MAINTENANCE The north stormwater infiltration system should be maintained as warranted from annual inspections using the inspection ports. See the ADS maintenance manual for more information. The maintenance for the system involves using a Jet Vac system per manufacturer recommendations to clean and remove sediment from the Isolator row of the system. This maintenance activity should be anticipated every 3 (+/-) years and is likely to cost $2,400. This results in approximately $800 per year that should be budgeted for this maintenance. The design life of the stormwater infiltration system is 75 years with an estimated replacement cost of $76,000. 6.5 EAST STORMWATER INFILTRATION SYSTEM MAINTENANCE The east stormwater infiltration system should be maintained as warranted from annual inspections using the inspection ports. See the ADS maintenance manual for more information. The maintenance for the system involves using a Jet Vac system per manufacturer recommendations to clean and remove sediment from the Isolator row of the system. This maintenance activity should be anticipated every 3 (+/-) years and is likely to cost $3,300. This results in approximately $1,100 per year that should be budgeted for this maintenance. The design life of the stormwater infiltration system is 75 years with an estimated replacement cost of $143,000. APPENDIX A: STORM FACILITY INSPECTION FORM Chapter 6 - Storm Drainage Design 6-44 City of Bozeman Design and Construction Standards Stormwater Facility Inspection Form Section 1: General Information Facility ID: Facility Type: Choose an item. Date/Time: Click or tap to enter a date. Owner: Contact: Inspector’s Name, contact info: Choose an item. Location/Access info: Type of Inspection: ☐ Routine, Dry Weather ☐ Routine, Wet Weather ☐ Complaint Driven ☐ Other: __________________ Section 2: Weather and Discharge Information Most recent precipitation or melt: Temperature: Is a stormwater discharge occurring? ☐ Yes ☐ No If yes, what is the source and quality of discharge? Is an illegal discharge occurring? ☐ Yes ☐ No If yes, what is the source and quality of discharge? Section 3: Facility Maintenance Priority ☐ Low: Stormwater facility appears to be functioning as designed. Continue scheduled maintenance. ☐ Medium: Stormwater facility requires minor to moderate sediment and vegetation maintenance to mitigate the risk of flooding, waterway pollution, and infrastructure failure. ☐ High: Stormwater facility requires significant sediment dredging, vegetation removal, and/or infrastructure repairs to restore function. Notes, Findings & Recommendations: Inspector’s Signature: ________________________________ Date: ___________________ Chapter 6 - Storm Drainage Design 6-45 City of Bozeman Design and Construction Standards Section 4: Qualitative Analysis Components # Items Conditions Results Notes and Required Actions General Degraded, missing, or inadequate Yes 1.1 Accessibility maintenance access? No ☐☐ Trash, sediment, and waste within 1.2 Debris ☐Yes and around the facility? ☐ No Overgrown or dead cattails, Yes 1.3 Vegetation woody shrubs, weeds, grass, and ☐ trees? ☐ No Infrastructure Damaged inlet pipe, outlet pipe, Yes1.4 ☐ Condition outfall structure, or fencing? ☐ No Facility Condition Pretreatment Bay Clogged, obstructed, or filled 2.1 ☐ Yes or Facility pretreatment forebay or facility? ☐ No 2.2 Storage Bay Clogged or filled storage bay? ☐ Yes ☐ No Stagnant water with infiltration Groundwater or Yes 2.3 greater than 48 hours post-rain ☐ Standing Water event? ☐ No 2.4 Flow Path Clogged or obstructed flow path? ☐ Yes ☐ No Barren or exposed surfaces on Yes 2.5 Side Slopes ☐ Facility’s side slopes and bottom? ☐ No Maintenance Maintenance Plan Is there a written plan specific to ☐ Yes 3.1 or Agreement this facility? ☐ No Yes 3.2 Implementation Is there evidence of maintenance? ☐ ☐ No Chapter 6 - Storm Drainage Design 6-46 City of Bozeman Design and Construction Standards Section 5: Quantitative Analysis Vegetation Cover type % Within facility Notes Bare ground Aquatics Grasses/Herbaceou Trees >3” DBH Shrubs Total 100 Elevation Analysis Location Reading (ft) Elevation (ft) Notes SRV#CP Control Point SRV#1 Inlet SRV#2 Outlet SRV#3 Center SRV#4 North of Center SRV#5 East of Center SRV#6 South of Center SRV#7 West of center SRV#8 Berm or overflow SRV#9 Summary Chapter 6 - Storm Drainage Design 6-47 City of Bozeman Design and Construction Standards Section 6: Facility Maintenance Inspection Exhibit Chapter 6 - Storm Drainage Design 6-48 City of Bozeman Design and Construction Standards Photo 1 description Photo 2 description Section 7: Photo Log APPENDIX B: INFILTRATION SYSTEM MAINTENANCE MANUAL Isolator® Row Plus O&M Manual 2 Looking down the Isolator Row Plus from the manhole opening, ADS Plus Fabric is shown between the chamber and stone base. StormTech Isolator Row Plus with Overflow Structure (not to scale) The Isolator® Row Plus Introduction An important component of any Stormwater Pollution Prevention Plan is inspection and maintenance. The StormTech Isolator Row Plus is a technique to inexpensively enhance Total Suspended Solids (TSS), Total Phosphorus (TP), Total Petroluem Hydrocarbons (TPH) and Total Nitrogen (TN) removal with easy access for inspection and maintenance. The Isolator Row Plus The Isolator Row Plus is a row of StormTech chambers, either SC-160, SC- 310, DC-780, SC-800, MC-3500, MC-4500 or MC-7200 models, are lined with filter fabric and connected to a closely located manhole for easy access. The fabric lined chambers provide for sediment settling and filtration as stormwater rises in the Isolator Row Plus and passes through the filter fabric. The open bottom chambers allow stormwater to flow vertically out of the chambers. Sediments are captured in the Isolator Row Plus protecting the adjacent stone and chambers storage areas from sediment accumulation. ADS Isolator Row and Plus fabric are placed between the stone and the Isolator Row Plus chambers. The woven geotextile provides a media for stormwater filtration, a durable surface for maintenance, prevents scour of the underlying stone and remains intact during high pressure jetting. The Isolator Row Plus is designed to capture the “first flush” runoff and offers the versatility to be sized on a volume basis or a flow-rate basis. An upstream manhole provides access to the Isolator Row Plus and includes a high/low concept such that stormwater flow rates or volumes that exceed the capacity of the Isolator Row Plus bypass through a manifold to the other chambers. This is achieved with an elevated bypass manifold or a high-flow weir. This creates a differential between the Isolator Row Plus row of chambers and the manifold to the rest of the system, thus allowing for settlement time in the Isolator Row Plus. After Stormwater flows through the Isolator Row Plus and into the rest of the chamber system it is either exfiltrated into the soils below or passed at a controlled rate through an outlet manifold and outlet control structure. The Isolator Row Plus FlampTM is a flared end ramp apparatus attached to the inlet pipe on the inside of the chamber end cap. The FLAMP provides a smooth transition from pipe invert to fabric bottom. It is configured to improve chamber function performance by enhancing outflow of solid debris that would otherwise collect at the chamber's end, or more difficult to remove and require confined space entry into the chamber area. It also serves to improve the fluid and solid flow into the access pipe during maintenance and cleaning and to guide cleaning and inspection equipment back into the inlet pipe when complete. The Isolator Row Plus may be part of a treatment train system. The treatment train design and pretreatment device selection by the design engineer is often driven by regulatory requirements. Whether pretreatment is used or not, StormTech recommend using the Isolator Row Plus to minimize maintenance requirements and maintenance costs. Note: See the StormTech Design Manual for detailed information on designing inlets for a StormTech system, including the Isolator Row Plus. 3 Inspection The frequency of inspection and maintenance varies by location. A routine inspection schedule needs to be established for each individual location based upon site specific variables. The type of land use (i.e. industrial, commercial, residential), anticipated pollutant load, percent imperviousness, climate, etc. all play a critical role in determining the actual frequency of inspection and maintenance practices. At a minimum, StormTech recommends annual inspections. Initially, the Isolator Row Plus should be inspected every 6 months for the first year of operation. For subsequent years, the inspection should be adjusted based upon previous observation of sediment deposition. The Isolator Row Plus incorporates a combination of standard manhole(s) and strategically located inspection ports (as needed). The inspection ports allow for easy access to the system from the surface, eliminating the need to perform a confined space entry for inspection purposes. If upon visual inspection it is found that sediment has accumulated, a stadia rod should be inserted to determine the depth of sediment. When the average depth of sediment exceeds 3" (75 mm) throughout the length of the Isolator Row Plus, clean-out should be performed. Maintenance The Isolator Row Plus was designed to reduce the cost of periodic maintenance. By “isolating” sediments to just one row, costs are dramatically reduced by eliminating the need to clean out each row of the entire storage bed. If inspection indicates the potential need for maintenance, access is provided via a manhole(s) located on the end(s) of the row for cleanout. If entry into the manhole is required, please follow local and OSHA rules for a confined space entry. Maintenance is accomplished with the JetVac process. The JetVac process utilizes a high pressure water nozzle to propel itself down the Isolator Row Plus while scouring and suspending sediments. As the nozzle is retrieved, the captured pollutants are flushed back into the manhole for vacuuming. Most sewer and pipe maintenance companies have vacuum/JetVac combination vehicles. Selection of an appropriate JetVac nozzle will improve maintenance efficiency. Fixed nozzles designed for culverts or large diameter pipe cleaning are preferable. Rear facing jets with an effective spread of at least 45” are best. StormTech recommends a maximum nozzle pressure of 2000 psi be utilized during cleaning. JetVac reels can vary in length. For ease of maintenance, ADS recommends Isolator Row Plus lengths up to 200' (61 m). The JetVac process shall only be performed on StormTech Isolator Row Plus that have ADS Plus Fabric (as specified by StormTech) over their angular base stone. Isolator Row Plus Inspection/Maintenance StormTech Isolator Row Plus (not to scale) Isolator Row Plus Step By Step Maintenance Procedures Step 1 Inspect Isolator Row Plus for sediment. A) Inspection ports (if present) i. Remove lid from floor box frame ii. Remove cap from inspection riser iii. Using a flashlight and stadia rod,measure depth of sediment and record results on maintenance log. iv. If sediment is at or above 3 inch depth, proceed to Step 2. If not, proceed to Step 3. B) All Isolator Row Plus i. Remove cover from manhole at upstream end of Isolator Row Plus ii. Using a flashlight, inspect down Isolator Row Plus through outlet pipe 1. Mirrors on poles or cameras may be used to avoid a confined space entry 2. Follow OSHA regulations for confined space entry if entering manhole iii. If sediment is at or above the lower row of sidewall holes (approximately 3 inches), proceed to Step 2. If not, proceed to Step 3. Step 2 Clean out Isolator Row Plus using the JetVac process. A) A fixed floor cleaning nozzle with rear facing nozzle spread of 45 inches or more is preferable B) Apply multiple passes of JetVac until backflush water is clean C) Vacuum manhole sump as required Step 3 Replace all caps, lids and covers, record observations and actions. Step 4 Inspect & clean catch basins and manholes upstream of the StormTech system. ADS “Terms and Conditions of Sale” are available on the ADS website, www.adspipe.com The ADS logo, StormTech®, the Isolator® Row Plus and the Green Stripe are registered trademarks of Advanced Drainage Systems, Inc. © 2025 Advanced Drainage Systems, Inc. #11081 5/25 CS 4 21) B)1) A) Sample Maintenance Log Date Stadia Rod Readings Sedi- ment Depth (1)–(2) Observations/Actions InspectorFixed point to chamber bottom (1) Fixed point to top of sediment (2) 3/15/11 6.3 ft none New installation. Fixed point is CI frame at grade DJM 9/24/11 6.2 0.1 ft Some grit felt SM 6/20/13 5.8 0.5 ft Mucky feel, debris visible in manhole and in Isolator Row Plus, maintenance due NV 7/7/13 6.3 ft 0 System jetted and vacuumed DJM adspipe.com 800-821-6710 APPENDIX C: MAINTENANCE ACKNOWLEDGEMENT Acknowledgement of Stormwater Facilities Maintenance Requirements PROPERTY OWNER: Lattice Materials NAME OF PLAN/DEVELOPMENT: UTSUS MAJOT LOT/BLOCK/SUBDIVISION: Lot 2A, Block 5, Amended Nelson Meadows Sub Property Owner hereby acknowledges that they are required to maintain all stormwater facilities on the Property pursuant to Bozeman Municipal Code sec. 40.04.720. This requirement is binding on any successor or assign olthe Property Owner listed above. The City requires stormwater facilities be constructed and adequately maintained on the Property in order to maintain the health, safety and welfare of City residents. Adequate maintenance is defined as keeping the stormwater thcilities and all components thereofin good working condition so that these stormwater facilities continue to perform in accordance with the design intent. Should the Property Owner fail to adequately maintain stormwater facilities, the City may enter upon the Property and lake such steps as are necessary to correct deficiencies. The City may assess against the Property Owner fbr the cost ofany repairs or necessary maintenance by any means provided for in the Bozeman Municipal Code. By signing below Property Owner acknowledges they have read this document and the applicable provisions ofthe Bozeman Municipal Code, and they agree to the maintenance requirements for all stormwater facilities on their Properfy. I]Y: (Property Owner) DAI'E