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02-23-15 Work Session Agenda Memo and Comments CITY OF KALISPELL CITY COUNCIL WORK SESSION AGENDA MONDAY, FEBRUARY 23, 2015 - 7:00 P.M. CITY HALL COUNCIL CHAMBERS 201 FIRST AVENUE EAST CALL TO ORDER DISCUSSION ITEMS 1. 2015 Design and Construction Standards PUBLIC COMMENT MAYOR/COUNCIL/CITY MANAGER REPORTS ADJOURNMENT FOR YOUR INFORMATION Next Regular Meeting – March 2, 2015, at 7:00 p.m. – Council Chambers Next Work Session – March 9, 2015, at 7:00 p.m. – Council Chambers Reasonable accommodations will be made to enable individuals with disabilities to attend this meeting. Please notify the City Clerk at 758-7756. February 10, 2015 Comments Received on Draft Design and Construction Standards 1. Dave Steely – LHC Inc. – Comments received via phone call a. Special Provision – Section 02600 – Water Distribution i. Subsection 3.4.D.1 – Should clarify that if a sample port is not available for contractor to take a bacteriological sample, the contractor will be responsible to install a temporary service and also remove it after the testing is completed. ii. Added the following text: “If sample location is not available, the Contractor shall be responsible to install a service saddle, corporation stop, and necessary service piping for sampling purposes at no cost to the City. After all testing is complete, the Contractor shall turn off and cap the corporation stop, and remove all service piping at no cost to the City.” b. Special Provision – Section 02720 – Storm Drain Systems i. Subsection 3.2.D – TV Inspection - Dave was concerned that the cost to pay for a video inspection of new mains would significantly increase the cost of construction. ii. I explained that the contractor is only required to pay for repeat television inspections. The first inspection is completed by the City prior to acceptance. If a defect is discovered, or if the test cannot be completed the first time (for example, pipe bedding in the pipe, etc.), then the contactor would be required to either hire a company to perform the inspection according to City requirements, or pay City crews to perform the repeat inspection. iii. Attempted to make the text clearer by bolding text as follows: “Pay all costs incurred in repeat television inspections or television inspections performed solely for Contractor benefit.” 2. Tom Anderson, Doug Hammerberg – Glacier Precast – Meeting with City Staff a. Requested Con-Seal CS-212 be added to list of approved manhole joint seals. i. Added the product to the approved list based on review of the product. b. Concerned about the requirement for gasketed or booted joints being required at all storm manholes and inlet structures. There are circumstances, when gasketed or booted joints cannot be provided because of constructability constraints. This can be for a variety of reasons, but mostly due to precast mold limitations and barrel joints on structures being in conflict with design pipe penetrations. i. Added note to Storm Standard Details: “ALL PIPE CONNECTIONS NOT CONSTRUCTIBLE AS DETAILED SHALL BE SUBMITTED TO CITY ENGINEER FOR REVIEW.” 201 1st Avenue East, P.O. Box 1997, Kalispell, MT 59903 –Phone (406)758-7720 – Fax (406)758-7831 www.kalispell.com 3. Brandon Theis – Robert Peccia and Associates Inc. – via email on 2/2/2015 a. 4.2.1.F.I.c & 4.2.2.A.III.d.ii: On our Whitefish projects, we have been installing Hydromatic Separators on their street reconstruction project. Is WQ treatment something that the City would look at doing on a case-by-case basis on street projects or is it simply “off the table” and exempt? I’m not the biggest fan of Hydromatic Separators, but it has been nice on site development jobs up there that we have been able to show that the City is making attempts at providing WQ treatment on their projects. Not so much of a comment as an observation…I think it is easier for the private sector to swallow the WQ treatment pill if they see the public sector setting a clear example. i. On the street reconstruction projects, we consider treatment devices on a case by case basis, but typically fulfill our obligations through our good housekeeping in the right-of-way (street sweeping, inlet cleaning, leaf pick-up, etc.) b. Chapter 4, Table 6: Is the ARC I Condition used anywhere in the standards or is it shown for reference only? i. For reference only footnote added to table. c. 4.6.1.C: What about subsurface filter systems such as the “Jellyfish”. I think “Underground treatment facilities are not permitted” really ties our hands on tight sites. There are a bunch of underground filter systems that are really good….as long as they are maintained. And that’s my guess why this language is in there…nothing ever gets maintained. But, there are maintenance agreements in place on all these systems. Is this maybe more of an enforcement issue than a design methodology issue? I would just hate to see the city close this door. There are a ton of great subsurface systems out there that can do a lot of good on the WQ treatment. i. Text changed to say, “Underground treatment facilities are not permitted, except for those meeting minimum requirements of section 4.6.3I.” ii. Allows technologies approved by Technology Acceptance Protocol – Ecology (TAPE) and Technology Acceptance and Reciprocity Partnership (TARP) to be used. d. 4.6.2.C.I: Maybe make a clarification that this calculation needs to be on the ARC III Condition. I was wondering if calculating the CN value using the distributed method could be replaced with the composite method. I seem to remember that Ian and I have struggled with this in the past. i. Changed text to say, “The water quality volume is the runoff from the first 0.5 inches of rainfall from a 24 hour storm using Arc III condition, or as otherwise required by the current MS4 Permit.” ii. Requirement for distributed method was removed. e. 4.6.3.B.II.a.i: Would a grass filter strip or stone/sand diaphragm or mechanical filter/separator system work for the WQ pretreatment requirement on a subsurface infiltration system? You would have a WQ flow then, not a volume. Reason I ask is that if a subsurface infiltration system is to be used, the reason is probably because there is not much room for treatment volume. i. Modified Standards to refer to section 4.6.3.F.VIII which discusses pretreatment options. Page 2 of 8 f. Lastly, I was wondering if the outfall BMP idea we spoke about last spring has gained any momentum. We were talking about some type of a program where money would be set aside to do regional treatment systems. Those systems could feasibly collect and treat more storm water for less money and the best part is that they would actually be maintained. Seems like a program like this could provide more “bang for the buck”. i. Following is the response to Mr. Theis: “As far as the outfall treatment devices, we did discuss this idea, but didn’t move forward with it at this time. There were several things to work through with that idea. One of the main issues is following our permit which requires developments to treat stormwater on-site. But there were also some logistical issues to consider like: • How to size a regional treatment facility that works at full build- out, but also with low initial use. • We have over 70 outfalls and most of them are hard to access. • With regional treatment, the responsibility is on the City to operate and maintain. There is no incentive for a development to follow good housekeeping guidelines on their site. • How do we collect money for a regional treatment device, and what happens with the untreated stormwater while funds build for the treatment site/device? The more we discussed it, the more complicated it got. The idea is good, and we have been able to do this on a couple of occasions (South Meadows, Willows subdivision, etc.), but even those sites were for individual developments.” 4. Toby McIntosh –Jackola Engineering – via email on 2/9/2015 a. Section 1.1.2 – I understand the intent of this section but my concern as a design engineer is how do we design for a standard that is not potentially in place until a future date. A thought would be to limit the length of time an approval is valid before construction begins. For example the DEQ water and sewer approvals are valid for 3 years before a resubmittal is required. i. This provision is to protect the City for projects that remain dormant for several years and then decide to move forward with the design as originally approved. ii. Section 3.1.6 states that the MFE approval will expire with DEQ’s original design approval for construction. iii. No modifications were made to the Standards. Page 3 of 8 b. Sections 1.10.1 and 1.10.2 – Our surveyor was out, so I have not confirmed if this is an issue, but I wasn’t sure what the survey laws or practices allow in terms of re-setting of property corners or perpetuating property corners. Can a surveyor file or record “bearing markers” for the purposes of reestablishing a monument or can a monument be replaced from these “bearing markers” without retracing the boundary? On section 1.10.2 can a plastic cap be used? I know the plastic caps for property corners are more common and if they are located under a riser and cover, they would be protected from damage. i. Contacted local Professional Land Surveyor (Ryan Mitchell), he suggested referencing the requirements of the State as follows: When a street is to be reconstructed, prior to any excavation, a thorough search shall be made for existing intersection monuments. If found, such monuments and any other survey monuments likely to be disturbed or destroyed, shall be preserved by or under direction of a Professional Land Surveyor in accordance with MCA 70-22-115. All monuments set shall meet the requirements of ARM 24.183.1101. Monuments set in pavement or concrete driving surfaces shall be placed inside of a cast iron monument box. c. Section 2.3.2C – I am assuming the daily reports are for only the City owned improvements and not the private lot development? i. Yes. The section applies to “all utility and roadway construction projects.” d. Section 3.1.7E – Do you want international feet? It seems that we often use survey feet, but I would have to verify with our surveyor. i. Yes. The City uses International Feet units for the Montana State Plane Coordinate System. e. Section 3.4.4F – Is the City open to deviation requests on the 2% max grade leading into an intersection? It doesn’t take much grade on a site to easily exceed 2% and visually 2% slopes appear pretty flat, especially over relatively short distances. i. AASHTO and MDT recommend a max of 3% for 75 feet to develop an adequate stopping distance landing for vehicles. This grade into an approach is based on “wet” road conditions and a deceleration rate of 11.2 ft2/s. For “icy” road conditions, deceleration rates are lower and the City errs on the safe side. The City requires a max 2% grade for 60 feet coming into an intersection. The grade is shallower, but the landing is also shorter. ii. A deviation from the Standards for this condition would need to be justified by the Design Engineer and approved by the City Engineer. f. Section 3.4.7 – Street Subbase – MPWSS section 02234 allows both crushed and uncrushed subbase material, while the City is requiring the crushed material with the fractured face. I have not spoken to local contractors to see if a crushed 3” minus is a commonly produced material so maybe having the fractured face is not a big issue. With proper gradations, my experience has been that the uncrushed material becomes well keyed when compacted. i. City Staff does not recommend a change to this requirement. Fractured faces do provide better interlock of aggregates. Additionally, if fractured faces aren’t required, there is no way to verify the material has been screened for maximum size. Page 4 of 8 g. Section 3.4.9 – I am assuming that the requirement for sidewalk is only along the subject property’s frontage on these streets? i. Yes. h. Section 4.1.3E – I understand the nature and intent of this section, the one thing that is a challenge (especially on small commercial lots) is that to develop a property and meet the flow control and water quality requirements in the manual, it is almost impossible to not concentrate flow to some extent. On larger subdivisions or larger properties where channel flow is likely to develop, this is a much easier criteria to meet. i. Yes, this can be a difficult provision if the development outflows to an undeveloped property. However, this provision is necessary to protect these adjacent property owners. ii. Typically, outflows are channelized, when connected into a downstream conveyance system. In this case, downstream property owners are protected and this is a non-issue. iii. No changes are recommended for this section. i. Section 4.2.1.E.IV – Is this just saying we can’t get a deviation to “ignore” a section in the code? Because I know we often need deviations to the standards for newly developed sites (ie pipe size, slopes, setbacks etc). i. Yes. Deviations are only granted in accordance with section 4.2.1.G. j. Section 4.2.2.F (c & e) Exemptions – As you and I discussed, the City being exempt from the storm water requirements imposed on all other development doesn’t seem appropriate when the requirements in these standards are a result of the EPA MS4 permit. Along the same lines, this section lists maintenance projects by the City that are exempt. Do these maintenance activities apply to privately owned infrastructure? i. The MS4 Permit for the City requires private developments and redevelopments to complete Water Quality treatment onsite. Likewise, the City is required to implement a Stormwater Program which includes “Good Housekeeping” such as street sweeping, leaf pick-up, and inlet cleaning; “Erosion Control” such as permitting, training, and implementation; “Illicit Discharge”; and “Public Education / Particiapation” such as school classroom education, carwash kits, educational mailings, and surveys. ii. Last year the City: 1. Removed about 3,000 CY of sweepings from the streets a. ~250 dump truck loads 2. Picked up about 5,000 CY of leaves a. ~415 dump truck loads 3. Cleaned 250 storm inlets 4. Trained employees on Pollution Prevention iii. The City isn’t exempt from MS4 requirements, but is required to meet the requirements in a different way. The City works hard to meet these requirements. Page 5 of 8 k. Section 4.4.3.C.I Sub-level Structure Feasibility – This section requires a minimum of one boring per 10,000 SF. Is this the lot area? How does this compare to the minimum lot size in the City (i.e. more than one boring per lot per single family residence)? MT DEQ does allow for a reduction in the number test pits in septic field work based on certain criteria. Will the City consider a reduction in the number of test pits for larger developments? Does this 10,000 SF requirement apply to both subdivisions and commercial development? My thought is that a commercial development will often receive additional engineering work beyond the typical residential project (ie geotechnical investigations including recommendations for foundations, backfill, subgrade preparations, etc) and therefore requiring the monitoring of groundwater through a high water season may unnecessarily impact the often fast timeline commercial projects experience. i. The square footage pertains to the sub-level structure, not the lot. ii. The City will not consider a reduction in the number of test pits for large commercial developments. iii. The 10,000 square foot sub-level structure area applies to both commercial and residential. However, not many residential structures would have sub- level areas equal to or greater than 10,000 square feet. iv. Groundwater monitoring during seasonal high ground water conditions is necessary to determine if sub-level structures are feasible. v. No changes to the current text are recommended. l. Section 4.5.1.C – Similar comment to 4.1.3.E. i. See previous response. m. Section 4.5.3.E – The infiltration rates listed in the HSG classifications do not appear to correlate with typical infiltration rates in section 4.6.3.B and what I would expect to see. i. Infiltration rates listed in the Hydrologic Soil Groups (HSG)is based on reference materials, and was listed for reference only. Soil group classifications should be based off of the Web Soil Survey. ii. Reference infiltration rates were removed from the HSG descriptions. n. Section 4.6.3.D.II.e – What is considered high concentration of oil and grease and how is this established? i. The design engineer and Public Works reviewing engineer will need to use engineering judgment to determine if high concentrations of oil and grease would be expected. Parking lots for a proposed vehicle or heavy equipment service shop may have higher expected oil and grease concentration than a clothing or office retail. ii. Staff does not recommend a change to this section. o. Section 4.6.3.D.VI.e – From my experience a 1” or ¾” minus drain rock is likely a standard item from gravel suppliers. Standard products will be more cost effective. i. This hasn’t come up as an issue in the past. ii. 3/8” pea gravel is readily available and will meet this requirement. p. Section 4.6.3.G.III.h Dry Swales – Is the 1.1 inch rain event referring to the 2009 WQV standard that has been reduced to 0.5 inches? i. Yes. The text in the Standard has been modified to reflect 0.5 inches. Page 6 of 8 q. Section 4.7.5.B.II.a – Depth to limiting layer is called out as >5 feet while the water quality section for infiltration facilities is listed as >3 feet. i. No change was made to the Standards. r. Section 4.7.6.A.III – I was happy to see that underground detention is being added to the manual, but to not allow infiltration in these systems is not appropriate in all situations. Again for commercial development this is much more critical than larger subdivision projects. To meet the planning and zoning requirements, typical parking layout criteria, and these regulations results in commercial projects are frequently squeezed for space. In urban drainage, infiltrating runoff is one way to reduce overall runoff volumes and discharge to surface waters. The requirement for water quality BMP’s upstream of detention will help mitigate clogging of infiltration basins. Additionally, we often do not have City storm drainage infrastructure to connect to, therefore once you collect storm water and pipe it underground, it is often impossible to daylight to surface infiltration. I realize that not all sites are appropriate for infiltration, but with the requirements for drainage submittals, we feel the appropriateness of infiltration utilizing underground structures should be considered on a case-by-case basis. i. Most soils in Kalispell have relatively slow infiltration rates. Where infiltration rates are adequate, above surface facilities provide the best visual monitoring. ii. If there is no other choice for storm detention, the design engineer will need to show the soils are adequate for infiltration, adjacent properties are protected, structures are protected, and meet the other requirements for a design deviation as required in the standards. iii. A change in the text of the Standards is not recommended. s. Section 4.7.8.A.II – I am assuming that a drainage parcel is only required in subdivisions and not in a single lot commercial development. If this is the case, please condition the section. i. The section already referred to Section 4.10, but was made more specific by referring to 4.10.2 which explains that commercial projects typically do not require a drainage parcel unless more than one lot would be served by the facility. t. Section 4.7.8.B.VI – Some commercial properties are less than 200 feet wide and may not be able to maintain a 200 foot setback to a school etc. if located adjoining the property. Will the City review this on a case by case basis? i. If a development cannot meet this requirement, then fencing or some other safety measure would be necessary to deviate from the standard. u. Section 4.7.8.D.I – We feel that 3H:1V side slopes are acceptable. In the manual the dry swales, biofiltration, wetponds, and bioswales all allow up to 3:1 slopes. In review of the Stormwater Manual for Eastern Washington, they allow detention pond slopes up to 3:1. With a stability analysis they even allow for steeper. I agree if space exists to allow flatter slopes, this is better. i. Pond side slopes were increased from 4H:1V max to 3H:1V max. v. Section 4.8.4 – A general comment on culverts is the analysis should consider inlet and outlet conditions. If analyzed purely on Manning’s flow, you may not be getting the controlling flow conditions. i. Flow control type was already listed in 4.8.4.B.II. ii. To make the required analysis clearer, added section f, requiring inlet or outlet flow control type. Page 7 of 8 w. Section 4.8.5.C.II – Are the HGL requirement of 0.5 feet freeboard applicable in the 100 year design events? I am assuming it isn’t since the requirement is to design pipes for the 10 year event with consideration to the 100 year events. i. 0.5 feet of free board applies to the 10 year event. During the 100 year event, the non-flooded width of the roadway should be evaluated. x. Section 4.9.3.A.I – I am assuming that the “professional” referred to in ESC preparation applies to SWPPP Administrators? i. Added the following text to the Standards: “For projects greater than 1 acre requiring a state SWPPP, the ESC must be prepared by a certified SWPPP Administrator.” Page 8 of 8