HomeMy WebLinkAbout2010-09-01 MSCWMO Preliminary Review Letter 4
MIDDLE ST. CROIX WATERSHED MANAGEMENT ORGANIZATION
1 380 WEST FRONTAGE ROAD, HIGHWAY 36 e`
STILLWATER, MINNESTOA 55082
Phone 651.275.1136 x22 fax 651.275.1254 www.mscwmo.org
MSCW s °
September 1, 2010 �.
Mr. Eric Johnson
Oak Park Heights
14168 Oak Park Blvd. N. P.O. Box 2007 gf
Oak Park Heights, MN 55082
RE: First Presbyterian Church Parking Lot Reconstruction - Preliminary Review •
Dear Mr. Johnson,
The Middle St. Croix Watershed Management Organization (MSCWMO) received required submittal items on July 24th,
2010 for the proposed First Presbyterian Church Parking Lot Reconstruction Project, located within MSCWMO
boundaries and in the City of Oak Park Heights. The proposed project qualifies for full review under the MSCWMO 2006
Watershed Management Plan (WMP).
The project, as submitted, meets all Policies and Performance Standards contained within Section 5.0 of the MSCWMO
WMP. MSCWMO staff recommends that the City conditionally allow the project to move forward as scheduled, with the
understanding that the applicant must complete the MSCWMO review process. The project will reviewed by the full
MSCWMO board at the next regular board meeting.
This approval does not constitute approval by the city of Oak Park Heights. The enclosed checklists contain detailed
information on project review qualification and the policies and performance standards of the WMP. MSCWMO review
process information can be downloaded from www.mscwmo.org. Feel free to contact me at 651- 275- 1136 x22 or
ACarolan @mnwcd.org if you have any questions regarding these comments.
Sincerely,
Amy arolan
Middle St. Croix Watershed Management Organization, Administrator
cc: Brett Emmons, FOR
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Middle St. Croix Watershed Management Organization Member Communities
Afton, Bayport, Baytown, Lakeland, Lakeland Shores, Lake St. Croix Beach, Oak Park Heights, St. Mary's Point, Stillwater, a West Lakeland
MIDDLE ST. CROIX WATERSHED MANAGEMENT ORGANIZATION
1 3 80 WEST FRONTAGE ROAD, HIGHWAY 36 ` ':.
STILLWATE R, MINNESTOA SS082 fi
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MSCWMO PROJECT REVIEW PROCESS — POLICIES AND PERFORMANCE STANDARDS
This document is for guidance. Applicants should consult the MSCWMO Watershed
Management Plan (WMP) for specific requirements.
All requirements of the policies and performance standards contained within Section 5 of the
WMP must be met before the MSCWMO Board will approve the project,
PROJECT NAME: 1ST PRESBYTERIAN CHURCH PARKING LOT - OAK PARK HEIGHTS
THE FOLLOWING POLICIES AND PERFORMANCE STANDARDS APPLY: [A checked box indicates compliance]
® Direct discharge of stormwater to wetlands and all other water bodies without water quality
treatment is prohibited. WMP Section 5.1.4, Policy Item 1
Ej Sources of water pollution shall be identified through the MSCWMO data collection
program and corrected through the application of BMPs. WMP Section 5.1.4, Policy Item 2
LE All hydrologic studies shall analyze the 24 -hour two- (2.75 inch), ten- (4.15 inch) and one
hundred -year (5.9 inch) critical rainfall event, with the critical duration defined as that event
causing either the highest water surface elevation or the largest peak discharge in an area or
both. Any study must use consistent methodology for the pre- development and post-
development land use conditions. The methodology must be approved by MSCWMO.
WMP Section 5.1.4, Policy Item 3
® Newly developed or redeveloped areas will be limited to the predevelopment or existing
rate of runoff or to a rate within the capacity of downstream conveyance systems,
whichever is less, and no increase in the volume or rate of runoff from newly developed
areas will occur in areas where natural outlets do not exist. In sub -areas of a landlocked
watershed, development shall not increase the predevelopment volume or rate of discharge
from the sub -area for the 10 -year return period event. WMP Section 5.1.4, Policy Item 4
El Runoff will be minimized through on -site infiltration or prevented through reduction in
impervious surfaces to the largest extent possible before detention ponds are used. WMP
Section 5.1.4, Policy Item 5
Site design practices that may have only a minor negative impact on peak flow and volume,
such as the use of buffer strips along receiving waters and drainage swales, will be
promoted to achieve compliance with the water quality performance standard. WMP Section
5.1.4, Policy Item 6
Middle St. Croix Watershed Management Organization Member Communities
Afton, Bayport, Baytown, Lakeland, Lakeland Shores, Lake St. Croix Beach, Oak Park Heights, St. Mary's Point, Stillwater, & West Lakeland
Z Applicants must secure any flowage easements that would be required to accommodate the
stormwater management facilities. These easements will be granted up to the 100 -yr flood
level. WMP Section 5.1.4, Policy Item 7
® Applicants will provide the MSCWMO with 100 -year flood levels on the ponds, lakes, and
streams as parcels are developed. WMP Section 5.1.4, Policy Item 8
® The MSCWMO has adopted the Washington County Floodplain Regulations. (Appendix
H). WMP Section 5.1.4, Policy Item 9
Z Project must meet the Design Standards for Structural Stormwater Management Measures
of the State of Minnesota Stormwater Manual, November 2005, or the most recent edition at
www.pca. state. mn. us / water / stormwater /stormwater- manual.html. WMP Section 5.1.4,
Performance Standard 1; WMP Section 5.2.4, Performance Standard 1
Design requirements for bioretention basins:
Z Adequate pretreatment upstream of bioretention practice(s)
Z Construction phased so that impervious area construction is complete and
pervious areas have established vegetation before stormwater is introduced
into bioretention practice(s)
El Planting plan detailing establishment of vegetation suitable for hydrology
of basin
Z The design permeability rate through the planting soil bed must be high
enough to fully drain the stormwater quality design storm runoff volume
within 48 hours. [Recommended: Move underdrain to the top of the
gravel blanket to allow for additional infiltration]
® Easy access provided for routine maintenance of infiltration practice(s)
Maintenance plan clearly identifies long -term maintenance schedule and
responsibility
Z Secondary outlet provided
El Separation from seasonally saturated soils or bedrock is 3 feet or more
►1 Enhanced volume runoff controls will be designed to retain on -site the first %2 inch of runoff
for all impervious areas plus '/ inch of runoff for areas with compacted soils. WMP Section
5.1.4, Performance Standard 2
a. Impervious areas or surfaces are defined as a surface in the landscape that impedes
the infiltration of rainfall and results in an increased volume of surface runoff.
b. Compacted soils are defined as surfaces in the landscape where the underlying soils
are compacted by construction or other activity that impedes the infiltration of
rainfall and results in an increased volume of surface runoff.
c. In redevelopment scenarios, volume control standards apply only to areas of new
construction, where soils are compacted, runoff characteristics are changed, or
vegetation is removed.
►1 No increase in rate of runoff leaving the site from pre- development to post - development
conditions generated by the 24 -hour two- (2.75 inch), ten- (4.15 inch) and one hundred -year
Middle St. Croix Watershed Management Organization Member Communities
Afton, Bayport, Baytown, Lakeland, Lakeland Shores, Lake St. Croix Beach, Oak Park Heights, St. Mary's Point, Stillwater, ft West Lakeland
(5.9 inch) critical rainfall events. WMP Section 5.1.4, Performance Standard 3; WMP
Section 5.2.4 Performance Standard 2
El A Stormwater Pollution Prevention Plan (SWPPP) that meets the National Pollutant
Discharge Elimination System (NPDES) requirements must be submitted to and approved
by the MSCWMO for all projects undertaking grading, filling, or other land alteration
activities which involve movement of earth or removal of vegetation on greater than 10,000
square feet of land (See Appendix J for NPDES requirements). WMP Section 5.1.4,
Performance Standard 4; WMP Section 5.2.4, Performance Standard 3
SWPPP Requirements:
Z Description of the nature of the construction activity
Z Address the potential for discharge of sediment and/or other potential
pollutants from the site
Identify a person knowledgeable and experienced in the application of
erosion prevention and sediment control BMPs who will oversee the
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implementation of the SWPPP and the installation, inspection and
maintenance of the erosion prevention and sediment control BMPs before
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and during construction
Z Identify who will have the responsibility for long -term operation and
maintenance of the permanent stormwater management system
® Identify a chain of responsibility with all operators on the site to ensure
that the SWPPP will be implemented and stay in effect until the
construction project is complete, the entire site has undergone final
stabilization, and a Notice of Termination has been submitted to MPCA
►1 Narrative describing the timing for installation of all erosion prevention
and sediment control BMPs
Location and type of all temporary and permanent erosion prevention and
sediment control BMPS along with procedures to be used to establish
temporary BMPs as necessary for the site conditions during construction
Z Standard plates and/or specifications for all BMPs used on the project
F2 Site map with existing and final grades, including dividing lines and
direction of flow for all pre and post - construction stormwater runoff
drainage areas located within the project limits
® Site map including impervious surface areas and soil types; area of each
must be noted (in square feet or acres)
Ej Location of areas not to be disturbed
Z Location of areas where construction will be phased to minimize duration
of exposed soil areas
es Identify all surface water and wetlands within %z mile of the project that
will receive stormwater runoff from the construction site
Z Methods to be used for final stabilization of all exposed soil areas
El Describe procedures to routinely inspect the construction site (once every •
7 days and within 24 hours after a rainfall event greater than 1/2 inch)
Z Describe practices to properly manage and dispose of solid waste
® Describe practices to properly manage hazardous materials
Middle St. Croix Watershed Management organization Member Communities
Afton, Bayport, Baytown, Lakeland, Lakeland Shores, Lake St. Croix Beach, Oak Park Heights, St. Mary's Point, Stillwater, & West Lakeland
E Describe practices for external washing of trucks and other construction
vehicles (concrete trucks, etc.)
El Describe spill prevention plan
® Describe measures to address sanitary and septic waste
Z Direct discharge of stormwater to wetlands and all other water bodies without water quality
treatment is prohibited. WMP Section 5.1.4, Performance Standard 5
:/ Predevelopment conditions shall assume "good hydrologic conditions" for appropriate land
covers as identified in TR -55 or an equivalent methodology. The meanings of "hydrologic
soil group" and "runoff curve number" are as determined in TR -55. However, when
predevelopment land cover is cropland, rather than using TR -55 values for cropland, the
following runoff curve numbers (RCN) shall be used. These curve numbers represent
midrange values for soils under a good hydrologic condition where conservation practices
are used and are selected to be protective of the resource waters. WMP Section 5.1.4,
Performance Standard 6
Hydrologic Soil Group Runoff Curve Number
A 56
B 70
C 79
D 83
ESI Conversion of high - permeability soils shall be avoided and these soils shall be targeted for
infiltration. WMP Section 5.1.4, Performance Standard 7
Z Lowest floor elevations of structures built adjacent to stormwater management features and
other water bodies must be a minimum of two feet above the 100 -year flood elevation and a
minimum of two feet above the natural overflow of landlocked basins. The landowner or
developer is required to provide MSCWMO with the location of the 100 -year flood elevation,
natural overflow elevation, and lowest floor elevations. WMP Section 5.1.4, Performance
Standard 8
Buffer zones of =flowed natural vegetation shall be maintained or created upslope of
delineated wetland edges, ordinary high water elevation, or floodplain of all water bodies
(wetlands, streams, lakes) in accordance with the Performance Standards relating to
wetlands, Section 5.3.4. WMP Section 5.1.4, Performance Standard 9
Detention facilities will be designed to attenuate peak flows and provide on -site infiltration
in high - permeability soils, natural depressions, and swales. WMP Section 5.1.4,
Performance Standard 10
Eg The MSCWMO shall require proper erosion and sediment control throughout the watershed
to prevent siltation and sedimentation of streams, lakes, wetlands, and other areas of the
watershed. WMP Section 5.2.4 Policy Item 1
Middle St. Croix Watershed Management Organi.zation Member Communities
Afton, Bayport, Baytown, Lakeland, Lakeland Shores, Lake St. Croix Beach, Oak Park Heights, St. Mary's Point, Stillwater, & West Lakeland
Z Both temporary (during construction) and permanent (long -term) erosion control will be
required on newly developed or redeveloped land in MSCWMO undertaking grading,
filling, or other land alteration activities which involve movement of over 100 cubic yards
of earth or removal of vegetation on greater than 10,000 square feet of land. WMP Section •
5.2.4 Policy Item 2
El Existing agricultural activities will be exempt from the performance standards listed in
WMP Section 5.2.4. MSCWMO will require buffers from waterbodies and support
agricultural BMPs. New agricultural activities must conform to the performance standards
listed in WMP Section 5.2.4. WMP Section 5.2.4 Policy Item 3
Z Construction is prohibited on slopes greater than 12 percent. Twelve percent (12 %) slopes
are defined as lands having average slopes 12% or greater over horizontal distances of fifty
feet (50) or more. WMP Section 5.2.4 Performance Standard 4
Z Construction is prohibited within 40 feet of the top of blufflines in urban areas and 100 feet
in rural areas. Blufflines are defined as a line along the top of a slope connecting points at
which the slope, proceeding away from the waterbody or adjoining watershed channel,
becomes less than twelve percent (12 %). The location of the bluffline shall be certified by a
registered land surveyor or the Zoning Administrator. WMP Section 5.2.4, Performance
Standard 5
Z Land alteration activities are prohibited within twenty (20) feet of the top of the bluff. Top
of bluff is defined as the highest point of a bluff with an average slope exceeding 12 %.
WMP Section 5.2.4, Performance Standard 6
Z Buffer zones of unmowed natural vegetation shall be maintained or created upslope of
delineated wetland edges, ordinary high water elevation, or floodplain of all water bodies
(wetlands, streams, lakes) in accordance with the Performance Standards relating to
wetlands, Section 5.3.4. WMP Section 5.2.4 Performance Standard 7
Middle St. Croix Watershed Management organization Member Communities
Afton, Bayport, Baytown, Lakeland, Lakeland Shores, Lake St. Croix Beach, Oak Park Heights, St. Mary's Point, Stillwater, Et West Lakeland