§ 5. Requirements for improvements, construction plans and design standards.

a.

Monuments. Monuments shall be set at the PC and PT and PRC of street lines, and at other locations required by the director of public works. Approved concrete monuments shall be used to mark the boundaries of the subdivision. Locations of all monuments shall be indicated on the subdivision plan. Iron pins shall be installed at each corner, property line angle point and at any other point to sufficiently define each lot, as determined by the director of public works and in accordance with accepted land surveying practices.

b.

Street design standards.

1.

Harmony with other streets. Streets in any subdivision shall be in harmony with existing or proposed thoroughfares as shown on any plan of development adopted by the commission, especially with regard to safe intersections with such thoroughfares, and shall follow the general contours of the land with a location and grade the preserves to the greatest extent possible the natural, terrain, trees and other significant natural, manmade, and scenic features. All streets in any subdivision shall have free access to or shall be continuations of one or more accepted town streets or state highways. Consideration shall be given to providing street right-of-way extensions to abutting undeveloped properties, and where necessary, temporary cul-de-sacs, so that a safe, convenient circulation system is provided in the opinion of the commission.

2.

Classifications. The commission shall classify or reclassify all the streets within or abutting the subdivision with the following classifications, and all streets shall be laid out, designed and constructed in accordance with the following classifications:

Arterial street: Existing or proposed as shown on the comprehensive plan of development adopted by the commission or intended to accommodate presently or at any future time traffic other than that of the immediate neighborhood, as determined by the commission, and where projected daily traffic is expected to be greater than 3,000 ADT.

Collector street: Any street other than an arterial street which is intended now or in the future to conduct traffic between local streets or between a local street and arterial street as determined by the commission. Minor collector streets are where projected daily traffic is expected to be between 250—1,000 ADT. Major collector streets are where projected daily traffic is expected to be between 1,000—3,000 ADT.

Local street: Any street whose primary function is to give access to properties only and which is not and will not in the future be likely to be used by traffic other than that having origin and destination upon such streets, as determined by the commission. Local streets include culs-de-sac and loop streets. A local street, which is or may be longer than 2,000 feet, shall be considered a collector street. Local streets are expected to have projected daily traffic of up to 250 ADT.

	Residential Districts
Road Classification	Right-of-Way Width	Pavement Width
Arterial	50 feet	30 feet
Collector	50 feet	28 feet
Minor	50 feet	24 feet

 

	Business or Industrial Districts
Road Classification	Right-of-Way Width	Pavement Width
Arterial	60 feet	36 feet
Collector	60 feet	34 feet
Minor	60 feet	30 feet

 

3.

Culs-de-sac. Culs-de-sac, dead-end streets with turnarounds, will be allowed under the following conditions:

a)

To provide access to undeveloped rear land surrounded by subdivided land, or to solve a topographic problem.

b)

As a temporary measure pending future development of adjoining land in which case provision shall be made in the turnaround for continuing the street later, and for reversion of any resulting excess right-of-way to abutting property owners.

The turnaround diameter shall be at least 110 feet and it shall have a minimum pavement radius of 50 feet to the outside curb.

Culs-de-sac shall not be longer than 600 feet measured from the center of the turnaround to the nearest street intersection.

The transition curve entering into the cul-de-sac shall have a minimum pavement radius of 100 feet, to create a "tear drop" shape as shown in the details.

There shall be no driveway curb cuts within the transition curves and no more than three driveways on the circle.

4.

[ Gradient. ] Minimum gradient for streets shall be not less than 1.0 percent. Maximum gradient shall not be more than 8.0 percent.

5.

Angle of intersections. Intersections between streets shall be at an angle of not less than 80 degrees for a distance of not less than 175 feet, unless specifically approved by the commission. Intersecting right-of-way lines at intersection shall be connected by a curve of at least 20 foot radius.

6.

Street jogs. Street jogs with centerline offsets of less than 200 feet shall be prohibited.

7.

Street names. Proposed street names are subject to approval by the commission. No street name phonetically similar to any street in use in the town shall be used.

8.

Boundaries of rights-of-way of existing streets. Boundaries of rights-of-way of all existing streets lying within or adjacent to any subdivision shall be relocated and laid out to meet the above standards to the extent which the commission in its discretion deems practicable and in the public interest. The intersections of existing streets shall be joined by curves as required above for new streets.

9.

Street construction standards. All streets and other facilities shall be constructed in accordance with standard specifications prepared by the department of public works and filed with the town clerk, which standards are included in graphic form within these regulations and are identified as "Technical Subdivision Regulations." Particular attention is directed to the street curbing standards, which are graphically defined in said "Technical Subdivision Regulations" and which are as follows:

All streets in any district shall have bituminous lip curbing with a six-inch reveal throughout, except where reinforced portland cement concrete pedestrian sidewalk ramps are required. On an existing public street, where no curbing presently exists, bituminous lip curbing shall be installed along the frontage of all proposed lots.

10.

Gridiron layouts. Gridiron layouts shall be avoided whenever possible. Local street patterns shall incorporate curves by following as closely as possible the natural features of land to be subdivided. Proposed straight local streets of 1,000 feet or more shall be subject to revision at the discretion of the commission.

c.

Lot and block standards.

1.

Block widths and lengths. Block widths shall not be less than 240 feet and block lengths shall generally not be longer than 1,200 feet nor less than 600 feet. In blocks longer than 1,000 feet, pedestrian crosswalks may be required to serve community facilities such as schools or shopping centers. Such walkways shall not be less than ten feet wide and shall be straight from street to street.

2.

Lots to front on streets. Each subdivision must front on a proposed public street having a right-of-way width of at least 50 feet, or on an existing public street.

3.

Lot arrangement. Lot arrangement shall be such that there will be no foreseeable difficulties for reason of topography or other natural conditions, in complying with zoning requirements in order to build on each lot. Lots shall not be of unreasonable depth, encouraging the later creation of a second building lot at the rear.

4.

Location of lot side lines. All side lines of lots shall be approximately at right angles to street lines unless a variance from this rule will give a better street or lot plan.

5.

Dimensions of corner lots. Corner lots shall be of sufficient dimensions so that any structure placed thereon shall conform to the building setback line of each street.

6.

Access of driveways to local streets. Where possible, lots shall be so laid out that the driveways serving the lots have access to a local street and not to a major road carrying general traffic.

7.

Septic systems. All proposed lots whose property lines are within 200 feet of an existing sanitary sewer line shall connect to such line. Otherwise, lots to be served by septic tank systems shall contain sufficient land of proper character to permit satisfactory performance of septic tank disposal fields. Where both private sewerage disposal and a well are to be located on the same lot, such lot should have an area of at least one acre. These areas may be reduced, but may not be less than the minimum requirement for the zone, where the subdivider submits a letter from the North Central Connecticut Health District, at the time of application to the commission, stating that the facilities as planned can be safely accommodated on each lot.

8.

Unavailability of public water/public sewer. If a town sewer and/or a public water supply are not available, such subdivision shall be submitted to the North Central Health District for a written report indicating the acceptability of each lot for a private water supply. Such report must be received at the time of application.

d.

Drainage improvements.

1.

Disposal of spring water and storm water system in general. The developer shall be required by the commission to carry away by pipe or open ditch, based on recommendations by the director of public works, any spring water that may exist on the proposed development. The developer shall have designed by a professional engineer, licensed in the State of Connecticut, a storm water drainage system that shall contain, where necessary, culverts, catchbasin, headwalls, storm sewers, detention and retention basins and other structures or facilities suitable to give the streets and adjacent lots proper drainage. This design shall be computed in accordance with the practices and procedures a set forth in the latest State of Connecticut Department of Transportation "Drainage Manual" and the soil conservation "Guidelines for Soil Erosion and Sediment Control" unless otherwise directed herein. It will be the responsibility of the developer to install an adequate stormwater drainage system, which will handle the run-off from a 25-year storm. The system shall be designed by the developer's professional engineer and submitted for approval by the director of public works. Three types of storm sewer pipes shall be acceptable. Reinforced concrete pipe, coated corrugated steel pipe and corrugated polyethylene pipe (smooth interior) are all acceptable pipe type options which must be specified appropriately based on soils, depth of cover and load capacities. The minimum size storm drainage pipe is 15-inch inside diameter. The minimum grade shall be not less than one-half of one percent and the cover over top of the pipes shall be not less than two feet. Standard State of Connecticut manholes, catchbasin and drain collectors, located with piping runs at intervals of not more than 300 feet, shall be used.

2.

Culverts. A culvert or other drainage facility shall, in each case, be large enough to accommodate potential runoff from its entire upstream drainage area, whether inside or outside of the subdivision. An analysis of downstream impact will be required in accordance with "Downstream Drainage", below. The developer's professional engineer shall determine the necessary size of facility based on anticipated runoff from a 50-year storm under conditions of total potential development permitted in the watershed. The culvert or drainage facility from the subdivision shall continue to a natural watercourse.

3.

Downstream drainage. The developer's professional engineer may be required by the director of public works to determine the effect of each proposed subdivision on the existing downstream drainage facilities outside the area of the subdivision. Where it is anticipated that the additional runoff incident to the development of the subdivision will overload an existing downstream drainage facility during a 50-year storm, the commission shall not approve the subdivision until the subdivider has made such provision for the improvement of such potential condition as the commission deems reasonable to require of the subdivider.

4.

[ Existing town streets. ] Where a subdivider of land proposes building lots on an existing approved town road, or where the tract of land to be subdivided presently receives storm water drainage from an existing town road or watercourse, it will be the responsibility of the developer to provide an approved storm water drainage system suitable to give the existing town street and adjacent lots of the proposed subdivision proper drainage.

5.

[ Drainage easement and flowage rights. ] Drainage easement and flowage rights shall be furnished by the developer in the name of the Town of Enfield in a form acceptable to the town attorney, where they are deemed necessary by the department of public works to install or maintain drainage installations or utility installations outside roadway limits, including ditches where necessary. Subject to utility design standards, the following easements shall apply:

a)

Twenty-foot minimum for sanitary lines.

b)

Twenty-five-foot minimum for storm water lines.

c)

As approved for all other purposes.

e.

Requirements for construction of facilities.

1.

All storm sewer pipe shall be reinforced concrete pipe, Class IV or the equivalent gauge (depending on size) coated corrugated steel pipe or corrugated polyethylene pipe (smooth interior). The minimum depth of cover shall be two feet over the top of the outside diameter of pipe, or as approved by the director of public works.

2.

Catch basins and drainage manholes should be spaced at a distance of not more than 300 feet on a roadway. In a parking area, one catch basin should cover not more than 9,000 square feet of paved area.

3.

On all commercial and industrial parking areas, the minimum thickness of blacktop shall be three inches; that is a 1½-inch compacted binder course with a 1½-inch compacted top course. The base underneath a parking area shall consist of good, firm, porous drainage material down to the frost line (subject to approval by the town engineer). On top of this material, a minimum of six inches of bank run gravel and two inches of processed stone above the gravel is required underneath the blacktop.

4.

Sanitary sewers. The minimum size for a house, commercial establishment, or industrial building is a six-inch diameter line from the building to the street lateral. This would consist of PVC pipe (SDR-35) with a minimum cover of five feet, required for traveled ways, parking lots or driveways.

Amount of Cover Material	Class of Pipe
5′	PVC (SDR-35)
4′—5′	PVC (SDR-18)
3′—4′	Cast Iron Pipe (Extra Heavy) PVC (SDR-35), and C-900 PVC
Minimum cover = 3″

 

(See Appendix A - Technical Specifications, pages 7—12 [Figs. 7—12] for further requirements.)

5.

Sidewalks shall be constructed with seven percent air-entrained concrete (4,000 psi), which shall conform to the latest specifications set by the State of Connecticut Department of Transportation. Slump shall be in the range of two to four inches. For sidewalk ramps, the wire mesh reinforcing shall be six inches by six inches, ten-gauge welded wire fabric complying with ASTM-185. Wire will be laid in a continuous roll being cut only for expansion joints. It shall pulled up to the center of the slab while pouring. A two-day curing period is required on all concrete sidewalk work.

All concrete will be sprayed with a wax-resin base compound that complies with ASTM C-309, Type II and ASHTO M-148, Type II, or equal, to prevent spalling.

The expansion joints shall be an asphalt type material, waterproof and conforming to ASTM-D994-53 and AASHTO-M-33-70. Thickness shall be three-eighths inches, and the distance between joints shall be no more than 20 feet with one dummy joint every five feet between expansion joints.

f.

Sidewalks. Portland cement concrete sidewalks, at least five feet in width, shall be placed six inches off the front property line across proposed lots in residentially-zoned areas and shall be constructed in accordance with standard specifications of the department of public works. A seeded grass strip shall separate the sidewalk from the roadway and shall slope to the curb of the traveled portion of the street. See technical specifications for roadway cross sections.

1.

Loop street and permanent cul-de-sac serving ten lots or less — no sidewalks;

2.

Loop street and permanent cul-de-sac serving 11 lots or more — sidewalks on one side, the location to be determined by the commission;

3.

Local street other than loop street and permanent cul-de-sac, sidewalk on one side, the location to be determined by the commission;

4.

Minor collector street — sidewalk on one side of the street, and at the discretion of the commission two sides of the street may be required;

5.

Major collector street — sidewalks on both sides of the street;

6.

Arterial street — sidewalks on both sides of the street.

Variations from sidewalk standards. The commission may require additional walks or may permit variations from the established sidewalk standards as set forth above upon a three-quarters vote of all the members.

In determining the appropriateness of such variation, the commission shall consider:

a)

Proximity to existing sidewalks and present and projected sites for schools, public facilities, open space, and shopping facilities;

b)

Present and projected dwelling unit density, the rural or suburban character of the neighborhood, and the present and potential pedestrian traffic in the area;

c)

The extent of environmental disturbance to be caused by the sidewalk construction such as removal of trees or other valuable natural or manmade features; or grading within or near areas of steep slopes, wetlands or watercourses.

g.

Public improvements associated with subdivisions of merged lots of record. As set forth in section 3.20.2 of the Enfield [Zoning] Ordinance, an applicant may apply for a special use permit to allow a division of merged lots of record. A companion subdivision application is also required. For subdivisions filed under this section, all subdivision regulation standards and requirements shall apply except as specifically set forth below:

1.

Street pavement width shall be constructed to a width consistent with the width of the pavement of the abutting street system but in no case less than 24 feet.

2.

Curbing shall be constructed to the standards existing in the abutting street system. If no curbing exists in the abutting street system, a street gutter shall be established to adequately carry stormwater.

The details of such improvements shall be approved by the commission upon receipt of a recommendation from the director of public works and town planner.