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HomeMy WebLinkAbout2006-05-25 BCWD Permit 05-04 to CSMiJ O WN'S kl.7ATER DISTRICT 1380 west Frontage Road, Hwy 36, Stillwater, MN 55082 Tel: 651- 275 -1.136 ext. 26 Fax: 651- 275 -1254 BROWN'S CREED WATERSHED DISTRICT PERMIT NO. 05 -04 Village at Oak Pare Heights Property Owner: CSM Corporation Date: May 25, 2006 Address: 500 Washington Avenue South Telephone: 612-395 -7000 Suite 3000 Fax: 612 --395 -7002 city/zip: Minneapolis, MN 55415 Project Location: SE coniei of 60 Street N. and Novak Ave. N, Oak Park 14eights, MN Affected Roles: Stormwater Mariagemeiit (Rule 2.0) Grading and Erosioii Coiitrol (Rule 3.0) Floodl)laiii and Drainage Alterations (Rule 7.0) Fees (Rule 8.0) �ii (R y n) Work Authorized: Perm iss is granted to do the work described i i`I the d o cuments referenced ill Table 1 and consistent with those documents as amended by the terms of this permit. hi the event of inconsistencies, the terms of this permit shall prevail, followed by the more recent document. Any ambiguity shall be resolved ill the manner that best furthers the water resource goals aiid purposes of Minnesota Statutes Chapt 103B amid 103 D. Mat eliAk 'SN'lihmitted.. Table I Materials /Documents Date Revised Ap form 12, 2005 Village at Oak Park Heights Grading, Ut ility and Details plan set _...... September September 12, 2005 May 23, 2006 Preliminary Geotechnical Exploration Report, GME C011SUI 1 11c .tune 30, 2005 Declaration for Stormwater Facility Maintenance May 17, 2006 Managers: Cram i_,eiser, President ° Gail l'Lrndsack, Vice - President ° Connie Taillon, TrC -CISL rer � Gerald Johnson, secretary ° Rick Vanzwol G eneral :ondxtio s I . This permit is a deterrn ination that the proposed activity, if conduicted in accordance with the conditions herein, shall comply with the rules and requirements of the BCWD. It does not constitute a finding that the activity complies with the requirements of any other local, state or federal agency, nor does it convey any property or other right to the applicant in the permitted activity o the land on which it is to occur. The applicant is responsible for com plying with the requirements of all agencies other than the BCWD, and for ensuring that it holds all property and other rights as are necessary to carry out the permitted activity. 2. This permit shall expire one year from the date of issuance unless renewed in accordance with Section 1.0 of the BCWD Rules. No work subject to the terms of the permit may be conducted after permit expiration. The permit may be transferred only in accordance with Section 1.0. 3. The Owner shall grant access to the site at all reasonable t1ines before, during and alter construction to authorized representatives of the BCWD for inspection of the activities authorized hereunder and compliance with the requirements of this permit, the BCWD Mules and the statutes relevant thereto. This ri of access shall be in addition to the access authority of the BCWD under existing law. 4. By issuing this permit, the BCWD does not direct the activity authorized herein or warTant the soundness of the applicant's design or methods in any respect. The BCWD waives no i mmunity o protection applicable to itself, an officer, an agent or an employee pursuant to this approval. 5. The address of the applicant as indicated on the permit application shall be the address for any mailing or notice by the BCWD in administering this perrnit. 6. Before commencing any activity covered. by this permit the pc:rrr shall sign the permit, indicating familiarity with its terms; transmit the signed copy to the BCWD by delivery, mail or fax; and confirm BCWD receipt thereof and payment of all fees and sureties due in accordance with section. S. )eci4 Condition 1. Permit to be issued upon meet:ing the I�econirnended Conditions Of "The Permit as set forth and in the memo to the BCWD Board of Managers, dated September 29, 2005, on the village at Oak :Park Heights by Lisa Tilman, FOR and Ryan Fleming, EOR. The Board made one additional condition of the permit that the applicant: demonstrate to the satisfaction of the District - L ",ngin -cer how f oatables will be kept from the drain the system.. Said memo is attached herein and incorporated into the permit. lt;: approved by ...a.. ,. i � . District administrator I hereby state that I am the owner of the property on which the work authorl"zed by thi's permit N to occur, or ani the authorized agent of said owner, and t hat I have reach and understand the ternis of the permit and the permittee's responsibilities hereunder. [Signature] Date: Print name, title and organization] Crala Leiser, President � Gail Pund&ic:k, vice - President � Connie: Tadlon, T�e�rsure� � Gerald Johnson, Secrctary� � Rick vanzwoi E MO E 101 OLIVIER RESOU RCES Date: S eptem ber 29, 2005 To: BCWD Board of Managers; Karen Kill, Administrator From: Lisa Ti loran and Ryan Flem Re: Permit No. 05.04 —Village at Oak Park Heights (Lowe's), Oak Park Heights, MN The following review of the above mentioned project located within the legal j Lirisd iction of the Brown's Creek Watershed District (BCWD) was conducted to determine compliance with the BCWD rules pursuant to the Board's permit issLiance determination for this project. GENERAL COMMENTS Development of the Village at Oak- lark. Fleights includes a Lowe's Home Improvement store and five smaller commercial retail buildings located east of Novak AvenLie and soLIth of State Highway 36 in oal Park Fleights, MN. The project includes six proposed buildings and associated parking lots on the 22 -acre site. The property is cL11 Undeveloped. Under existing conditions, aboLIt 14.5 acres of the site dr ain into the District. The majo •ity of this drainage flows into the pond behind the Applebee's Restaurant and the remaining drainage flows to the frontage road ditch. Under proposed conditi a additional 6.2 acres that is curren oLItside the BCWD hydrologic boundary will be redirected into the District from Middle St. Croix WMO. Drainage from aboLIt 21 acres of the site will be routed to a new wet detention and infiltration pond (see attached grading plan). OLitflow fi•0111 the new pond will be I•o to the existing Applebee's pond and will Ultimately discharge into Long Lake. Rule 2.0 STORMwATER MANAGEMENT Rate Control According to BCWD rule 2.4.1, part (a), it 111LIst be shown that the proposed development site will not increase peals stormwater flow for the 1.5, 1 and 100 -year, 24 -hoLtr storm events. ® Drainage fr0111 the constructed onsite pond Will be directed to an existing pond on the Applebee's property. The project proposes redirection of additional drainage to the Applebee's pond. To avoid overwhelming the Applebee's pond with the additional drainage, discharge rates to the pond mLIst not increase over the existing rates. ® The proposed pond will be l ined with clay to an elevation of 938.0 feet. The pond's main oLItlet, directing drainage to the Applebee's pond, is set at an elevation of 938.9 feet. At Malting A Difference Through Integrated Resource Managemer7t EOR INC. • 651 Hale Avenue North • oakdale, MN 55128 + Tel: (651) 770 -8448 • Fax: (651) 770 -2552 Purge 2 9/29/0 5 1041'D Development ReWeiv Village at Oak Park Heights, Oak Park Ileights 938.0 feet there is an outlet that connects to a rietworlc of drain tiles installed below the clay - lined portion of the pond. The networl( of drain the is intended to allow infiltration of runoff in the deeper native silty sand soils. Lining the rei nainder of the pond with clay will maintain open water for aesthetic purposes. ® The submitted HydroCAD model uses a Curve rIuniber of 70 for the existing site condition and a curve number of 92 for the proposed site condition. Drainage into the drain the network and infiltration from the pored are not niodeled. Models have a starting water elevation at the top of the clay lined portion (approximately 1 foot below the outlet to Applebee's Pond) and assume that any water rernaining below the outlet will enter the infiltration system. In actuality, water will begin entering the infiltration system as water levels rise above 938.0 feet. The riiethod for riiodeling the system is therefore conservative and will overestimate the r Llnoff rates out of the pond. The submitted resLrlts rneet BCWD requirements for rate control and are sLrmrnarized in Table I below. Table 1: Peak Runoff Rates as Submitted by Alliant En p leering Event (yi - ) Existing (efs) Pr oposed (cfs) 7 Onsite To A.jal)lebee's bond fi Proposed Pond to A plebee's Pond 1.5 4.3) 6 10 12.22 11.89 100 23.77 19.73 Drainage A rea 10.2 ac 20.7 ac" e "Approxirnately 0.9 acre of the developri drain out of the District Volume Control According to BC w D rule 2.4.1, part (b), it Must be shown that the proposed site will not increase stormwater volLIMes generated froni a 1.5 -year, 24 -hour event, excepting that from 5% irnpervioLrs cover ® Different volLrn control requirernerits apply in three distinct areas of the site: 1. The area covered by the TSMP cooperative agreement o The District's volLIIIIe control rule does not apply to 15.85 acres of the property on the basis of the execLrtior of the revised TSMP cooperative agreement among the District, the City of Oak. Parlc, Heights, and the City of Stillwater (See attached neap of Cooperative agreement area ol~ application). o Under proposed conditions, there is no restriction on the volLrrrie of runoff leaving the site from this area. 2. The area within the District's Legal Boundary but not covered under the cooperative agreement o Standard volume control requirements apply to the 3.78 acres of the site located within the legal boundary of the District, but I10t 111CILrded in the cooperative agreement. Page 3 9129/05 BC T1VD Development Revieiv V llage at Oak Pork Heights, Oak Park freights o The existing volrinle of rLIiloff leaving the site (including the 5% for the area in the legal boundary is 0.102 acre -feet. Under proposed conditions, this volume cannot be exceeded for this portion of the site. 3. The area currently outside the District's Hydrologic and Legal Boundary • Full voluine control (infiltration of the entire runoff voli.ime) is required for the 2.03 acres of drainage outside the District's legal and hydrologic boundaries that is not covered Under the cooperative agreement. • Under proposed conditions, the entire 0.491 acre -feet of rulIoff volume produced outside of the District that is be r edirected into the District must be in filtrated. The total volume leaving the site, therefore, should not exceed the sum of that produced by the area within the cooperative agreement and that produced under e xisti ng conditions within the Legal Boundary. Table 2 summarizes runoff vollrimes produced onsite including the 5% impervioi.is surface allowance for existing conditions. The relevant values used to evaluate compliance with BCWD Rules are shaded. The total volLiine leaving the site, there must not exceed 2.696 acre -feet. Table 2: Runoff Volumes Generated as Submitted by Alliant Engineering A total of 1.81 acre -feet drain ofl'site from the proposed pond in a 1.5 -year event. This sleets the BCWD r eq uirements. An alternative means to determine whether this pro j sleets BCWD req U irements is to calculate the required volrime of water that must be infiltrated. In this case the volume to be infiltrated equals the volLime produced offsite plus the difference in volume for the area within the legal boundary but outside the cooperative agreement. The volume to be infiltrated is then 0.707 acre- -feet. The pond volrIme between the 938 and 939 elevations is 0.709 acre -feet. This is the vo 1 i.ime we can reasonably expect to enter the drain tile network and infiltrate. Thus, the project also Meets the infiltration requiremellts under this analysis. ® A schematic outlining additional detail of the drain tile system is desired. The District would life to see that the distance between the bottom of the clay l iner and the top of the 6 --inch drain the is maximized to prevent compaction of the materials around and beneath the drain tile network during compaction of the clay liner. Existing (acre -feet) Proposed (acre -feet) Event �a�verecl by In Legal g Covered by n Legal g Outside Legal (Y��� e Cooperative p � Boundary Coo perative l Boundary Boundc`�� Boundar Agreement (riot �n Agreement (not in (not in hoop.) �ooCoop.) Coo o} 1.5 0.79 2 0.02 .25 4:: 9 1 0.3 8 4 0. 91 Draina 15.85 2.03 1 5.85 2.03 ).78 Area A total of 1.81 acre -feet drain ofl'site from the proposed pond in a 1.5 -year event. This sleets the BCWD r eq uirements. An alternative means to determine whether this pro j sleets BCWD req U irements is to calculate the required volrime of water that must be infiltrated. In this case the volume to be infiltrated equals the volLime produced offsite plus the difference in volume for the area within the legal boundary but outside the cooperative agreement. The volume to be infiltrated is then 0.707 acre- -feet. The pond volrIme between the 938 and 939 elevations is 0.709 acre -feet. This is the vo 1 i.ime we can reasonably expect to enter the drain tile network and infiltrate. Thus, the project also Meets the infiltration requiremellts under this analysis. ® A schematic outlining additional detail of the drain tile system is desired. The District would life to see that the distance between the bottom of the clay l iner and the top of the 6 --inch drain the is maximized to prevent compaction of the materials around and beneath the drain tile network during compaction of the clay liner. Page 4 9.. BCHID Developmew Review Village at Oak Palk Heights, Oak Park Heights Compaction of the subsurface soils around the drain tile could be minimized by using lightweight /wide tracked machinery for excavation and grading of the drain tile area. The option of a polyurethane pond lining with a soil blanket cover may reduce the need for compaction of a clay liner to ensure a sealed wet pond above the drain tile network. The conveyance culvert to the drain tile system slIOL€ ld be taken off line until all upstream drainage areas are completely restored. LangL €age emphasizing this should be included in the plan set. Pollutant Loadlin According to the BCW.D rule 2.4.1, part (c ), the proposed develop ment must not result in an increase in total loads of sL €spended solids, total nitrogen, or heavy metals, or exceed the total phosphorus concentration indicated in Appendix 2.2, BCWD rules, for the site receiving water. As modeled by the applicant using PondNet, the pond provides 59% removal of phospho €'Us with an outflow phospl101 concentration of 1.66 ppb. The maximL €m allowable inflow concentration for Long Lake is 250 ppb. Therefore, the pollutant loading standard has been met. Lake /Wetland Bounce —According to the BCWD rule 2.4.1, part (d), the proposed development ML €st €101 increase the bounce or duration of inundation for the 1.5, 10, or I00 -year 24 hour storm event in accordance with the limit specified in Appendix 2.3 of the BCWD € Llles. Modeling for this area of Oak Park. F eights has shown that drainage and ponding modifications have a negligible i mpact on the bounce and duration of downstream Long Lake. Bounce and duration effects are dampened as runoff makes its way through the numerous pond and pipe networks towards Long Lake. According to BCWD rule 3.2, all developers undertaking in land altering activities involving the movement of more than 50 cu. yd. or remove vegetation on more than 5,000 sq. ft. shall submit an erosion control plan and secure an erosion control permit from the District. The erosion control plan includes the following: ® Silt fence placed appropriately along the property boundary ® Silt fence for inlet protection ® Plan for permanent re- vegetation including seeding with native vegetation on pond slopes To meet BCWD requirements the following are necessary: • Temporary rock construction entrances at all access points • Riprap protection at pond inlets and outlets • Implementation schedule Page 5 9!29105 B (' R'D Development Re vie iv......... Village at Oak Park Heights, Oak Park Inc iglus Rule 4e0 LAKE, STREAM, AND WETLAND BUFFER REQUIREMENTS Buffer zone widths are dictated by the presence of a stream or tributary of Brown's Creek and by the quality of lakes or wetlands oil the development site. ® This rule requirement does not apply to the proposed project. Rule 5.0 SHORELINE AND STREAM BAND. ALTERATIONS According to BC WD rule 5.0, No pet shall construct or install a shoreline or streambank improvement below the ordinary high water nark of a waterbody, without first obtaining a District permit. a This rule requirement does not apply to the proposed project. Rule 6.0 WATERCOURSE AND BASIN CROSSINGS Placement of roads, highways and utilities in the bed of any waterbody in the District requires a District permit. m There are no watercourse or basin crossings proposed. Rule 7.0 FLOODPLA.IN AND DRAINAGE ALTERATIONS According to BC W D rule 7.3.1 all new residential buildings shall be constructed such that the lowest basement floor elevations are at a ill ill illI ri m of two feet above the 100 -year high water elevation. The lowest grade elevation in contact with the structure can be used instead of' the lowest floor only for a perched water basin, which must be demonstrated by the criteria listed under rule 7.3.1. ® The high water level of the proposed pond is 943.62 feet. All of the buildings are proposed as slab -on-grade structures. The building adjacent to the pond has a lowest floor elevation of 948.7 feet. All but one of the other proposed buildings have a lowest floor elevation of at least two feet above the high water level of the pond. The building in the northwest corner of the property has a lowest floor elevation of 944.2 feet, less than two feet above the 100 -year high water level of the proposed pond. The pond would have to reach an elevation of over 948 to flow overland toward the northwest building. However, water backed LIP in the storm sewers at the 100 -year elevation would not be fizlly contained in the storm sewer system and would result in ponding of water close to this building. Therefore, the condition for freeboard has not been fully met. BCWD 7.3.2 No person shall install a culvert, drainage tile, or other artificial means to remove or drain surface water without demonstrating to the District that they have provided for adequate Page G 9129/03 BC14 Development Review - Village at Oak Park Heights, Oak Park. Heights passage and no adverse impact oil upstream or downstream landowners or water quality, habitat or fisheries. ® The applicant has demonstrated that the proposed design provides adequate passage and coi - itainment of surface water oil the site. Designing the stormwater treatment facility to contain additional volumes, reduce peak discharge rates, and remove pollutants generated oil the proposed site, within the constraints of the District Stoi- mwater rules, satisfactorily demonstrates that impacts oil upstream and downstrearn entities will not be adverse. Rule 8.4 FEES Fees for this project as outlined below: 1. Grading or Alteration greater than 20 acres $2,000 Iff TOTAL FEES $2,444 Mule 9.4 SURETIES Sureties for this project are as outlined below: 1. Grading or Alteration (23.75 acres) $47,500 2. Stormwater Management Facilities *$418,750 ® TOTAL SURETIES YS466 *No S1017711'Vater Mgt Facilities surely is riccessaq if applicant can de ionstr•ate that the municipality has received equal or greater per, fonnance surety wnount fr•oln applrcar ?t. RECOMMENDED CONDITIONS OF THE PERMIT: Summary of the remaining tasks necessary to bring the project into compliance with the BCwD Rule is as outlined below: 1. Provide a schematic outlining additional detail of the drain the system showing the distance between the bottom of the clay liner and the top of the 6 -inch drain tile. 2. Include a note oil the plan set instructing that the drain the area beneath the pond will be excavated and graded with lightwelght /wide tracked equipment. 3. include a note oil the plan set instructing that r11110ff is to be directed away from the drain the systeill until the entire site is restored. Page 7 9129105 13C[VD Development Pevieiv Village at oak Park Heights, Oak Park Heights 4. Provide revised Erosion and Sediment control plan containing the following items: o Temporary rock construction entrances o Riprap protection at pond inlets and outlets o Implementation schedule 5. Devise lowest floor elevation of the northwest building to be at least 945.62 feet or alter storm sewer system using a method acceptable to the District to address the issue of potential flooding. 6. Provide necessary following surety a. Grading or Alteration surety b. Stormwater Management Facilities surety or proof that: the City of oal", Park Heights has received a Performance Surety of equal oz• greater alllount than 125% of the stormwater management facilities construction costs. 7. Provide stormwater facility maintenance agreement iii a form acceptable to the District and proof of recordation with washingtoil CoL111ty. Maintenance protocol specific to the drain the system should be included in this agreement. 8. Provide written confirmation that the diversion of waters from the Middle St. Croix WMO is in accordance with the rules and requirements of MSCWM0.