All streets, drainage, sewers and other required subdivision improvements shall be designed and constructed as provided herein and shall be subject to approval by the Commission and the Town Engineer.

All streets, including Arterial, Collector and Minor streets, and including private streets serving six (6) or more lots, shall be designed and constructed in accordance with the Requirements for the Acceptance of Roads by the Town of Westport adopted by the Representative Town Meeting on Sept. 9, 1964, as amended. Roads in private rights-of-way serving two (2) to five (5) lots only shall also be designed and constructed in accordance with such Regulations and Specifications, except that the aggregate total width of traveled path and gutters may be reduced to twenty (20) feet, subject to approval of the Town Engineer.

Storm drainage in connection with Arterial, Collector and Minor streets and in connection with private streets serving six (6) or more lots, shall be provided, designed and constructed in accordance with Requirements for the Acceptance of Roads by the Town of Westport, adopted by the Representative Town Meeting on Sept. 9, 1964, as amended. Private rights-of-way serving two (2) to five (5) lots shall be provided with such storm drainage as may be determined necessary by the Town Engineer to prevent erosion, to prevent storm water from crossing the traveled path and to provide adequate collection and disposal of storm water where the private right-of-way joins with an existing public street or a street that may be proposed for acceptance by the Town. Storm drainage in the subdivision shall also be designed and constructed in accordance with the following standards:

The Commission may require the installation of sanitary sewers in any subdivision located within or reasonably close to the public sanitary sewer system of the Town. Installation of new sewer lines may be required and capped in anticipation of a future sewer connection. Sanitary sewers shall be designed and constructed in accordance with the Regulations of the Westport Sewer Authority dated August 30, 1960, as amended, and shall be subject to the approval of the Sewer Authority and the Connecticut Department of Environmental Protection, where appropriate.

Bridges, box culverts, deep manholes, detention ponds, weirs, street signs, traffic signs and other special structures shall be designed in accordance with good engineering practice and shall be subject to approval of the Town Engineer.

All new electric and telephone lines shall be installed underground. The Commission may require the installation of water lines in any subdivision located within or reasonably close to the public water distribution system in the Town.

All property corners, angles and tangent points defining the property limits shall be either pinned or monumented. Monuments shall be provided at those locations indicated upon the subdivision map and unless noted herein, shall be installed in accordance with the Requirements for the Acceptance of Roads by the Town of Westport, adopted by the Representative Town Meeting on Sept. 9, 1964, as amended. All other property corners, angles and tangent points shall be pinned.

Monuments shall be precast of concrete having a twenty-eight day compressive strength of four thousand psi and shall be constructed with steel reinforcement, including four corner rods of minimum three-eighths inch diameter each. Monuments shall have minimum dimensions of four inches square at the top, seven inches square at the base and thirty-six inches in overall length. The top center of each unit shall be marked with a brass or bronze plug or drill hole. Survey pins shall be solid steel rods of minimum three-quarter inch diameter and thirty inch overall length.

Monuments and pins shall be installed after site grading has been completed and shall be either flush with, or with no more than two inches exposed above, finished grade. If the point of installation is exposed ledge, the point shall be marked with a brass plug in lieu of a monument and a drill whole or chiseled cross in lieu of a pin. Where site conditions preclude the installation of monuments or pins at specific locations, alternative marker locations shall be utilized at the discretion of the Town Engineer.

Street trees shall be planted on both sides of any proposed street and may be required on any subdivision side of an existing street. Trees shall be spaced not more than fifty (50) feet apart but subject to variations made necessary by driveways, street corners, walks and utility lines, and shall be located a minimum of five (5) feet from the edge of the pavement. Trees to be planted shall be at least 3 1/2 to 4 inches caliper as measured six (6) inches above the root crown. The type and species of tree shall be subject to the approval of the Tree Warden, and shall not include low branching trees or trees which cause damage to underground utilities, or which create a traffic hazard. Where the trees may interfere with utility poles and wires or underground utilities, or where soil and planting conditions may not be satisfactory, the Tree Warden may vary the required location for trees and may permit the location of required trees within the front fifteen (15) feet of the proposed lots. Trees shall be planted in accordance with the approved manner and conditions of the Tree Warden. Existing trees along the proposed street may be preserved to meet these requirements.

Sidewalks shall be installed in all pedestrian easements. The Commission may require the installation of sidewalks on existing and proposed and streets in the vicinity of schools, parks, and playgrounds and in other places where they are deemed necessary by the Commission for safety and convenience. Sidewalks shall be at least four (4) feet in width and shall be located within the right-of-way of the street. The Town Engineer may vary the required location for a sidewalk in unusual circumstances involving steep grades, ledge outcroppings, or where the sidewalk would require removal of a tree or utility pole which would add to the appearance of the street.

A sediment and erosion control plan shall be required pursuant to §37 herein for all subdivision applications where the cumulative area(s) of disturbance is one half (1/2) acre or more; and may be required for applications with less than one half (1/2) acre of disturbed area(s) if deemed necessary by the Planning and Zoning Commission.

Construction and installation of streets, storm drainage, sanitary sewers and other improvements required by these regulations shall not be considered authorized until the proposed subdivision maps, plans and documents have been approved by the Commission and all of the conditions of approval have been met with the exception of completion of improvements or posting of a bond to guarantee such completion. Construction and installation of streets, storm drainage, sanitary sewers and other improvements shall be carried out in accordance with procedures specified in the applicable Town regulation, as amended, and subject to the approval of the Town Engineer. The subdivider will be required to supply a certified "as-built" Mylar of the subdivision improvements prior to final release of the bond. This Mylar must conform to the standards of the Town Clerk for mylars to be filed upon the land records.

 

The minimum criteria for the design of all storm drainage systems and facilities shall be a 25-year storm and the maximum allowable total coverage.

Sufficient storm water pipe shall be installed within the subdivision to drain the proposed streets and to carry existing watercourses within the subdivision area. If in its judgment there will be no substantial danger from soil erosion or danger to the public health and safety, the Commission may permit the discharge of rivers and large streams in their natural courses and may permit the discharge of storm water and established watercourses in open ditches across proposed lots. All pipes and ditches shall be of such size, material and construction as will be sufficient to properly carry storm water expected to enter the pipe or ditch from the proposed subdivision and from other properties when developed which normally drain across the area of the proposed subdivision. Such pipe shall not be less than 15 inches in diameter with a minimum slope of 0.5% unless otherwise approved by the Town Engineer. The Commission may require the installation of additional drainage facilities, such as a detention pond, in order to maintain a zero runoff impact, in the subdivision where necessary to prevent flooding or soil erosion, to protect the public health and safety and to make the lots suitable for occupancy.

The discharge of all storm water shall be into suitable streams or rivers or into Town or State Highway drains with adequate capacity to carry the additional water. Where the discharge shall be into or through private property, proper easements and discharge rights shall be secured by the applicant. Where the discharge into or through private property consists of any storm water coming from an existing public street or a proposed street other than a private street or right-of-way, such easements and discharge rights shall also be secured by the applicant for the Town.

Where it is anticipated that the additional run-off resulting from the development of a subdivision will overload an existing drainage facility during a 10-year design storm flow, the Commission shall not approve the subdivision unless and until provision has been made for the improvement of said condition.

Storm drainage facilities shall be designed to achieve at least a zero impact runoff based on a minimum 25 year storm flood, unless otherwise approved by both the Flood and Erosion Control Board and the Town Engineer.

Street culverts and bridges shall be designed for a 100-year storm flow.