A. Stormwater Drainage: An adequate stormwater drainage system shall be utilized throughout all subdivisions or developments within the village. The system shall include stormwater conveyance in combination with one or more stormwater management basins. The system shall be designed and constructed to meet the applicable requirements of:
1. The Village:
a. The storm drainage and surface water control system shall be approved by the village engineer. Computations may be required for the entire watershed or drainage basin of which the subdivision is a part.
b. Special consideration shall be given to avoiding potential problems which may arise from storm water runoff onto adjacent properties.
c. Storm water runoff flowing onto a proposed development parcel from any upstream tributary areas shall be conveyed through the proposed development by a method of "bypass" or detained on site in addition to runoff storage required for the development. If upstream runoff is "bypassed" through the development, the location at which the bypass flow leaves the development shall not be changed. In addition, the bypass flow shall be attenuated through the development to the extent that the rate of the bypass flow shall not be increased over the rate at which it flows from the development site in its existing condition.
2. The State: The state, including, but not limited to, the plat act of the state of Illinois.
3. Lake County Watershed Development Ordinance (WDO): "Watershed development ordinance", Lake County storm water management commission, as adopted by the village.
4. United States Government Or Agency: Any applicable requirements and regulations of the United States government, or agency, including, but not limited to, requirements and regulations of the federal emergency management agency, federal insurance administration or environmental condition indicated on any flood hazard map of the federal flood administration of the United States department of housing and urban development.
a. The selection of methods for design of a storm water drainage system shall follow the hierarchy as found in section IV.B.1.d. (pg. 13) of the WDO.
b. Overland flow paths, including swales, and drainage ditches shall be designed to convey runoff for return frequencies up to and including one hundred (100) years with a runoff coefficient determined by the existing and proposed conditions including flood hazard areas.
c. Ditches and/or swales with culvert pipes shall be designed and constructed of the size and slope to transport the runoff flow as calculated by the above described methods. The slope from the shoulder line to ditch bottom shall not be steeper than four to one (4:1) and the back slope not steeper than four to one (4:1). Fill sections shall have a slope not greater than four to one (4:1). The minimum longitudinal slope shall be one percent (1%).
(1) Culverts under all subdivision roads shall have a minimum equivalent diameter of fifteen inches (15").
(2) Culverts under all lot access drives shall have a minimum equivalent diameter of twelve inches (12").
(3) Culverts shall be reinforced concrete pipe in accordance with the appropriate section(s) of the "Standard Specifications For Road And Bridge Construction", Illinois department of transportation, latest edition. Polyvinyl chloride ("PVC") pipe, in accordance with the appropriate section(s) of the "Standard Specifications For Road And Bridge Construction", will be allowed for culvert pipe only as approved by the village engineer.
d. Creeks, rivers, and storm water management basins shall be designed for a return frequency of one hundred (100) years with a runoff coefficient determined by the existing and proposed conditions.
e. The detention volume required shall be calculated using a rating curve based on maximum release rates of 0.04 cubic feet per second per acre for the 2-year, 24-hour storm event and 0.05 cubic feet per second per acre for the 100-year, 24-hour storm event. The release rate requirement shall apply to the hydrologically disturbed area of the ownership parcel unless the enforcement officer determines that specific locations of the development site have unique circumstances such that the release rate shall apply to a broader or smaller area.
f. (1) Storm water management basins, or the equivalent, shall be provided in the subdivision so that the runoff of surface water shall be limited in accordance with these provisions. Such storm water management basins, or the equivalent, shall be designed:
(A) To provide for the effect on property located downstream from such subdivision;
(B) To provide for the effect on areas surrounding the subdivision affected by rainfall and the surface water runoff from such subdivision;
(C) To take into effect any environmental conditions indicated on any flood hazard map of the federal emergency management agency, federal insurance administration and any applicable requirement or regulation; and
(D) In accordance with the provisions of this section, where waterways, channels, ditches, streams or rivers are traversed.
(2) Except where inconsistent with the watershed development ordinance (title 10, chapter 1 of this code), or except where inconsistent with good engineering practice as determined by the village engineer:
(A) All storm water management basins, or the equivalent, storm water management basin buffers, and the shorelines of ponds and streams, shall be planted and thereafter maintained with vegetation native to northern Illinois as described in the "Native Planting Guide" on file with the village, and such vegetation shall be approved in advance by the village engineer as appropriate to a specific site.
(B) All storm water management basins shall be graded to natural shape.
g. If storm sewers are to be provided for the conveyance of storm water, they shall be designed and constructed of the size and slope to transport the runoff flow from a 10-year frequency storm event. Overland flood routing shall be provided for flows exceeding the capacity of the storm sewers as required in subsection A4b of this section.
(1) Minimum storm sewer size for the main line shall be twelve inches (12").
(2) Storm sewer material shall be reinforced concrete pipe as described in the appropriate section(s) of the "Standard Specifications For Road And Bridge Construction", Illinois department of transportation, latest edition, unless otherwise approved by the village engineer.
(3) Storm sewers shall be laid straight in both horizontal and vertical planes between structures unless otherwise approved in writing by the village engineer.
(4) Storm sewers shall be constructed in accordance with the "Standard Specifications For Road And Bridge Construction", "Standard Specifications For Water And Sewer Main Construction In Illinois", the pipe manufacturer's recommendations, and these development standards.
(5) Manholes, catch basins and inlets shall be reinforced concrete as described in the appropriate sections of the "Standard Specifications For Road And Bridge Construction".
(6) Manholes shall be provided at:
(A) Changes in direction - horizontal or vertical;
(B) Changes in shape or size of pipe;
(C) Junction of pipes;
(D) Maximum spacing of manholes should be in accordance with the following:
Size Of Pipe
(Inches) | Maximum Distance (Feet) | ||
10-24 | 350 | ||
27-36 | 400 | ||
42-54 | 500 | ||
60 and greater | 1,000 | ||
(7) Inlets shall be provided at all low points and at other locations consistent with the terrain to collect and deliver storm water runoff to the storm sewers without causing excess inundation.
B. Sanitary Sewerage: Any individual sewage disposal systems (septic system) shall meet all the requirements of, and shall be approved by, the village and Lake County health department. Any other sanitary sewerage facilities shall meet all the requirements of, and shall be approved by, the Village, the Lake County Health Department, and the Illinois Environmental Protection Agency. In the event of conflict or inconsistency among the requirements of these jurisdictions, the most restrictive requirements shall apply.
C. Water Supply: Any individual water supply shall meet all requirements of, and shall be approved by, the Lake County Health Department. Any water supply designated as public water supply shall meet the requirements of the Village and the Illinois Environmental Protection Agency.
D. Utility Services:
1. Building services shall be constructed to connect with the utility service mains constructed within any street or thoroughfare, to serve each adjoining lot, tract or building site. Such building services shall extend from the main to a point at least eight feet (8') beyond the outside lines of the proposed roadway pavement in the street and at least one foot (1') beyond the outside lines of the proposed road pavement.
2. All such building services connected with utility mains constructed within any street or thoroughfare shall be located at the approximate centerline of each lot.
3. Upon completion of the construction of all such building service connections with utility mains, an accurate map or maps showing the exact locations of all such mains, together with manholes, shutoff valves and other similar facilities being a part thereof, by distances in feet from street lines, and of all such building service connections in distances in feet from the side lot lines, shall be filed in the Office of the Village Clerk. (Ord. 2007-O-20, 10-2-2007)
E. Street Construction: Except as otherwise provided by these subdivision regulations, construction of all streets and cul-de- sacs shall conform to the typical section drawings found in section 9-5-5, "Appendices", of this chapter. These standards are the minimum requirements. (Ord. 2017-O-21, 11-7-2017)
1. Ditches Or Storm Sewers: Either ditches or storm sewers of adequate size shall be provided for surface drainage. If ditches are constructed, the slope from shoulder line to ditch shall not be steeper than four to one (4:1) and the back slope not steeper than four to one (4:1). A two foot (2') minimum ditch bottom width shall be provided with a minimum longitudinal grade of one percent (1%) for grass lined ditches. Fill sections shall have a slope not steeper than four to one (4:1).
2. Exposed Areas: All exposed areas shall be reseeded or sodded to prevent erosion. Seeding and sodding shall conform to the appropriate sections of the latest edition of the "Standard Specifications for Road and Bridge Construction", as amended from time to time, which is expressly made a part of this subsection by reference.
3. Street Grades: The grades of all streets shall be no greater than seven percent (7%) and vertical curve lengths shall be designed for the appropriate design speed and in accordance with the IDOT "Bureau of Local Roads and Streets Manual". Except as otherwise provided herein, the plan and profile of streets shall be approved by the Village Engineer.
4. Street Intersection: At all intersections controlled by traffic signals, stop signs, or yield signs, each controlled street shall have a minimum distance of one hundred twenty five feet (125') (as measured from the centerline of the intersecting street) which shall be at a grade of no more than two percent (2%).
5. Pavement Standards:
a. Pavement cross section materials and widths shall comply with the typical sections in appendices A, B, C and D of this chapter.
b. All street pavements shall be designed by the structural design methods outlined in the Illinois Department of Transportation "Bureau of Local Roads and Streets Manual" and shall meet the minimum requirements and thicknesses indicated in appendices A, B, C, and D of this chapter.
c. The subgrade for all pavements shall be prepared in accordance with the applicable sections of the "Standard Specifications for Road and Bridge Construction". Prior to proceeding with pavement installation, the subgrade shall be inspected and approved by the Village Engineer for shape and bearing capacity. The bearing capacity shall be determined by "proof rolling" with a forty five thousand (45,000) pound rubber tired vehicle load which shall be provided by the developer's contractor. Deflections of more than one inch (1") under load shall be considered unsatisfactory. Unsatisfactory subgrade shall be reworked until the proof roll is acceptable.
d. After approval of the subgrade and prior to placement of the subbase or base course material, ground stabilization fabric shall be placed on the subgrade. The material and installation shall be in accordance with the appropriate sections of the "Standard Specifications For Road And Bridge Construction".
e. Subbase granular material and aggregate base course shall be one hundred percent (100%) crushed gravel or crushed stone of a CA-6 gradation meeting the respective requirements for subbase granular material, type B and aggregate base course, type B of the "Standard Specifications For Road And Bridge Construction". The material shall be placed to the required thickness determined by the structural design methods outlined in the Illinois department of transportation "Bureau Of Local Roads And Streets Manual" and shall meet the minimum requirements and thicknesses indicated in appendices A, B, C and D of this chapter.
f. The aggregate base course shall be installed and prepared in accordance with the applicable sections of the "Standard Specifications For Road And Bridge Construction". Prior to proceeding with placement of the bituminous binder and surface course, the base course shall be inspected and approved by the village engineer for shape and bearing capacity. The bearing capacity shall be determined by "proof rolling" with a forty five thousand (45,000) pound rubber tired vehicle load which shall be provided by the developer's contractor. Deflections of more than one-half inch (1/2") under load shall be considered unsatisfactory. All areas of the base course not meeting the proof roll requirements shall be reworked, or stabilized until the proof roll is acceptable.
g. One of the following road design options, or a combination thereof, shall be utilized, as determined by the village engineer:
(1) Option 1: Bituminous binder and surface course shall be placed to the required thicknesses determined by the structural design procedure or to the minimum thicknesses indicated on either appendix A, B, C or D of this chapter. The material and installation shall meet the requirements for bituminous concrete surface course, superpave, of the friction aggregate mixture, and Ndesign specified and bituminous concrete binder course, superpave, of the mixture composition, and Ndesign specified, in accordance with the most recent bureau of design and environment "Special Provisions For Superpave Bituminous Concrete Mixtures" and the appropriate sections of the "Standard Specifications For Road And Bridge Construction". The initial lift of surface course shall be installed to the top of the shoulder/gutter flag at an approximate cross slope of one percent (1%). For minor residential streets, this will provide for an initial surface course thickness of two and one-half inches (21/2") at the centerline and four inches (4") at the edge of pavement. When seventy five percent (75%) of the subdivision lots have been occupied by a building for which an occupancy permit has been issued, the initial surface course shall be edge grinded to a depth at the edge of pavement to allow for final surface placement as shown in appendices A, B, C and D of this chapter. The initial surface course along with the concrete shoulders and curbs and gutters shall be inspected and approved by the village engineer after edge grinding and prior to the placement of the final surface course.
(2) Option 2: Bituminous binder and surface course shall be placed to the required thicknesses determined by the structural design procedure or to the minimum thicknesses indicated on either appendix A, B, C or D of this chapter. The material and installation shall meet the requirements for bituminous concrete surface course, superpave, of the friction aggregate mixture, and Ndesign specified and bituminous concrete binder course, superpave, of the mixture composition, and Ndesign specified, in accordance with the most recent bureau of design and environment "Special Provisions For Superpave Bituminous Concrete Mixtures" and the appropriate sections of the "Standard Specifications For Road And Bridge Construction". The binder course shall be installed initially to the top of the shoulder/gutter flag at an approximate cross slope of one percent (1%). For minor residential streets, this will provide for a binder course thickness of two and one-half inches (21/2") at the centerline and four inches (4") at the edge of pavement. When seventy five percent (75%) of the subdivision lots have been occupied by a building for which an occupancy permit has been issued, the binder course shall be edge grinded to a depth at the edge of pavement to allow for surface placement as shown in appendices A, B, C and D of this chapter. The binder course along with the concrete shoulders and curbs and gutters shall be inspected and approved by the village engineer after edge grinding and prior to the placement of the surface course.
(3) Option 3: Bituminous binder and surface course shall be placed to the required thicknesses determined by the structural design procedure or to the minimum thicknesses indicated on either appendix A, B, C or D of this chapter. The material and installation shall meet the requirements for bituminous concrete surface course, superpave, of the friction aggregate mixture, and Ndesign specified and bituminous concrete binder course, superpave, of the mixture composition, and Ndesign specified, in accordance with the most recent bureau of design and environment "Special Provisions For Superpave Bituminous Concrete Mixtures" and the appropriate sections of the "Standard Specifications For Road And Bridge Construction". The surface course shall not be placed until at least seventy five percent (75%) of the subdivision lots have been occupied by a building for which an occupancy permit has been issued unless, at fifty percent (50%) occupancy, the developer agrees to place an additional one and one-half inches (11/2") of binder course, and then immediately thereafter puts the surface course in place.
h. Portland cement concrete pavements shall be placed to the required thickness determined by the structural design procedure. The material and installation shall meet the requirements of the appropriate sections of the "Standard Specifications For Road And Bridge Construction".
6. Shoulders And Curbs And Gutters:
a. Shoulders On Residential Streets: Shoulders on residential streets shall be Portland cement concrete shoulders in accordance with appendices A and B of this chapter and the appropriate sections of the "Standard Specifications For Road And Bridge Construction", except as modified herein. Turf shoulders on residential streets consisting of two feet (2') wide aggregate shoulders in lieu of the concrete shoulders only may be permitted as approved by the village administrator. One of the following shoulder design options, or a combination thereof, shall be utilized as determined by the village engineer:
(1) Option 1: Portland cement concrete shoulders shall be constructed at a minimum thickness of nine inches (9") and shall be nineteen inches (19") in width. Combination concrete curb and gutter, type M-3.12 shall be placed around all intersection radii. The curb shall be tapered to the gutter (shoulder) in a minimum three foot (3') length, tapering down from the return of the radius (point of curvature). Contraction joints shall be sawed and sealed at uniform intervals not to exceed fifteen feet (15'). Expansion joints shall be one inch (1") thick with two (2) no. 6 (3/4") smooth epoxy coated bars with greased caps and shall be constructed at intervals not to exceed sixty feet (60').
(2) Option 2: Combination concrete curb and gutter, type M-3.12 shall be constructed with a minimum gutter flag thickness of nine inches (9") and shall be nineteen inches (19") in width. Contraction joints shall be sawed and sealed at uniform intervals not to exceed fifteen feet (15'). Expansion joints shall be one inch (1") thick with two (2) no. 6 (3/4") smooth epoxy coated bars with greased caps and shall be constructed at intervals not to exceed sixty feet (60'). Curbs shall be depressed to one and one-half inches (11/2") at all driveways.
(3) Option 3: Turf shoulders shall be a minimum four feet (4') in width. Seeding or sodding shall be of a salt tolerant lawn mixture. A four inch (4") white edge line shall be placed continuously six inches (6") inside the bituminous edge of pavement. Two foot (2') wide mailbox turnouts shall be provided for all lots occupied by a building. Combination concrete curb and gutter, type M-3.12 shall be placed around all intersection radii. The curb shall be tapered to the gutter (shoulder) in a minimum three foot (3') length, tapering down from the return of the radius (point of curvature).
b. Curbs And Gutters On Commercial And Industrial Streets: Curbs and gutters on commercial and industrial streets shall be combination concrete curb and gutter, type B-6.12 in accordance with appendices A and B of this chapter and the appropriate sections of the "Standard Specifications For Road And Bridge Construction", except as modified herein. Portland cement concrete shoulders shall be constructed at a minimum thickness of nine inches (9") and shall be nineteen inches (19") in width. Combination concrete curb and gutter, type B-6.12 shall be constructed with a minimum gutter flag thickness of ten inches (10") on commercial streets and twelve inches (12") on industrial streets. Two (2) no. 4 (1/2 inch diameter) reinforcing bars shall be placed continuously in the curb and gutter, and shall be at a height of three inches (3") above the bottom of the concrete curb and gutter. Contraction joints shall be sawed and sealed at uniform intervals not to exceed fifteen feet (15'). Expansion joints shall be one inch (1") thick with two (2) no. 6 (3/4") smooth epoxy coated bars with greased caps and shall be constructed at intervals not to exceed sixty feet (60'), unless specifically approved by the Board of Trustees.
7. Signs: Signs bearing the names of the streets shall be erected at all street intersections. Signs and signposts shall meet the minimum requirements for similar signs and posts as shown and set forth in the latest edition of the "Manual of Uniform Traffic Control Devices for Streets and Highways" as prepared and published by the Illinois Department of Transportation of the State of Illinois. The signs shall have white letters on a green background. (Ord. 2007-O-20, 10-2-2007)
8. Trees: The following requirements for the planting of trees shall be applicable to all subdivisions within the corporate limits of the Village:
a. Size: Trees having a trunk diameter measured at breast height of not less than two and one-half inches (2.5") shall be planted along all streets where trees do not exist. This requirement will be satisfied and it is preferable if an equivalent number of trees of the same size are planted in a naturalistic way in the front yards of the abutting lots. Replacement trees required by title 11, chapter 1 of this Code shall be provided by the subdivider in addition to the trees required in this section.
b. Locations: Spacing of trees shall be between twenty five feet (25') and forty feet (40') (i.e., separation) depending on species selected, along public streets and shall be located, when within the public right-of-way, two feet (2') on center as measured from the right-of-way line, and when located on private property, not more than seven feet (7') on center from the right- of-way line.
c. Species: The only species of trees that shall be planted shall be those listed as permitted replacement trees in section 11-1-5 of this Code, or those approved by the Village Administrator or his/her designee.
d. Mix Of Trees: Not more than twenty five percent (25%) of the trees planted in a single subdivision or development shall be of one species.
e. Guarantee Required: Trees which do not survive eighteen (18) months after planting shall be replaced at the subdivider's expense. (Ord. 2014-O-04, 2-4-2014)
9. Native Plantings: The following requirements are for the planting of native plants (shrubs, grasses, wetland plants and others) and shall be applicable to all subdivisions within the corporate limits of the Village:
a. Location: Native plantings shall be incorporated into the landscape planning and design of any new subdivision, except where the Village Administrator, or his designee, determines in advance that such plants would not be sustainable or are inappropriate.
b. Species: Species of shrubs, grasses, wetland plants and others are listed in the "Native Planting Guide" on file with the Village and located at http://www.csu.edu/CERC/NativePlantGuide- Illinois 2004. (Ord. 2007-O-20, 10-2-2007)