Town of Derry, NH Article V Design and Construction Standards

§ 170-25 Lots.

A. General requirements.

(1) Each platted lot shall conform to Chapter 165, Zoning, of the Code of the Town of Derry.

(2) Whenever possible, side lot lines shall substantially be at right angles or radial to streets.

(3) Each lot must front on an approved street.

(4) Land of such character that it cannot be safely used for building purposes because of exceptional danger to health or peril from fire, excess drainage, flood, or other menace shall not be platted for residential occupancy, nor for such other uses as may increase danger to health, life, or property or aggravate the flood hazard, until appropriate measures have been taken by the owner or his agent to lessen the hazards.

(5) Each lot shall have its driveway access through its own frontage, and no driveway may be laid out such that its curb cut will be closer than 75 feet to an intersection of public streets.

(6) Minimum frontage requirements of Chapter 165, Zoning, must be continuous and uninterrupted.

B. Minimum lot sizes, unsewered areas. In the absence of municipal sewerage facilities, minimum lot sizes within all subdivisions shall, in addition to meeting the requirements of Chapter 165, Zoning, for the district wherein the subdivision is proposed, also meet the lot area requirements specified in Table A, Minimum Lot Area by Soil Type.[1] The form titled "Lot Area by Soil Type Calculation" shall be used for all lot area determinations referred to herein.[2] This requirement is subject to the following qualifications:

(1) Where more than one soil type is found on a lot, the methodology of the form titled "Lot Area by Soil Type Calculation" shall be used to determine the minimum lot area.

(2) Poorly and very poorly drained soils may be used as part of the computed lot area according to the following:

(a) Areas mapped as poorly drained soils may be utilized to fulfill 25% of the minimum required lot area provided that the non-wetland area is sufficient in extent and configuration to adequately accommodate all required utilities, such as sewage disposal and water supply, including primary and reserve leach field locations;

(b) Areas designated as very poorly drained, fresh or saltwater marsh or alluvial soils shall not be utilized to fulfill minimum lot area; and

(c) Except as set forth in Chapter 165, Zoning, no subsurface wastewater disposal system shall be constructed within 75 feet of any area of poorly or very poorly drained soil which also has been designated as a wetland under the items of Chapter 165, Zoning.

(3) Minimum lot areas for residential developments with greater than four bedrooms per unit and for commercial and industrial developments shall be determined as follows:

(a) For single-family residential use with five or more bedrooms per unit, the minimum lot area shall be proportionately larger than the lot area indicated in Table A[3] as determined by the formula:

[3] Editor's Note: Table A is included at the end of this chapter.

(b) For multifamily residential, commercial and industrial uses, required lot areas will be determined by the formula:

(c) Design flow, measured in gallons of wastewater discharged per day, shall be determined from Table 1008-1, Unit Design Flow Figures, contained in Part ENV-WS 1008.03 of the New Hampshire Code of Administrative Rules (August 1999 edition).

[1] Editor's Note: Table A is included at the end of this chapter.

[2] Editor's Note: This form is on file in the office of the Planning Board.

C. Determination of soil type.

(1) High-intensity soil survey mapping utilized by any applicant in demonstrating compliance with the minimum requirements of this section shall be prepared by a certified soil scientist in accordance with those standards established in a publication titled "High Intensity Soil Maps for New Hampshire" (SSSNNE Special Publication No. 1).

(2) The soil types listed below have one or more limiting characteristics that make soil type "NA" or require on-site investigation, no matter what other characteristics in the soil may be present:

	Soil Type	Minimum Lot Size
	5***H	NA, poorly drained soil
	6***H	NA, very poorly drained soil
	*75*H	NA, fill does not meet the standards for fill material (see Key to Soil Types)
	76**H	On-site evaluation needed
	NA means not allowed * means any slope number

(3) In areas not currently served by municipal sewer systems, it shall be the responsibility of the subdivider or his agent to provide adequate information to prove that the area of each lot is adequate to permit the installation of an individual sewage system.

D. On-site inspections. If deemed necessary, the Board may elect to visually inspect the property being subdivided. Under these circumstances, the developer may be asked to stake or flag proposed lot corners, wetland boundaries, where applicable, and/or roadway center lines on the ground for the purposes of facilitating such an inspection.

E. Dedication of lands.

(1) Areas set aside for and, where applicable, improved suitably as parks and playgrounds to be dedicated or to be reserved for the common use of all property owners by covenant in the deed, whether or not required by the Board, shall be of reasonable size and character for neighborhood playgrounds or other recreational uses.

(2) Where deemed essential by the Board, consistent with the Master Plan, and upon consideration of the particular type of development proposed, and especially in large-scale neighborhood unit developments, the Board may require the dedication or reservation of recreational or open space of a character, extent, and location suitable to the needs created by such development.

F. Test pits/percolation tests. In areas not served by public sewer systems, the applicant shall submit test pit and percolation test data sufficient to demonstrate that a suitable area exists on each platted lot for the construction of an on-site subsurface sewage disposal system meeting the requirements of the New Hampshire Department of Environmental Services.

G. Monumentation. Boundary monuments shall be installed at all turning points on platted lot lines and any other point the Board or its agent deems necessary to control the lines of streets, lots, easements, or rights-of-way. Four-inch by four-inch by thirty-six-inch reinforced concrete or stone markers shall be installed adjacent to all streets and shall be installed so as to protrude not less than three inches nor more than six inches above finished grade. Iron pins may be used at all other points and must be at least 36 inches long and protrude a nominal three inches above finished grade.

§ 170-26 Streets.

A. General.

(1) All new subdivisions shall meet the standards recommended by the State of New Hampshire Department of Safety, Division of Emergency Services, Bureau of Emergency Communications addressing standards guidelines. No street name shall be used which will duplicate or be confused with any street name already in use. Further, the use of persons' first names as street names shall normally be avoided.

[Amended 6-20-2012]

(2) Street names shall be subject to approval of the Chief of the Derry Fire Department and the Planning Board.

(3) The arrangement, character, extent, width, grade and location of all streets shall be considered in their relationship to existing or planned streets, to topographic conditions, and to public convenience and safety and their appropriate relation to the proposed use of the land to be served.

(4) Proposed streets shall conform, as far as practicable, to the Master Plan.

(5) The arrangement of streets in a proposed subdivision shall, in the discretion of the Planning Board, provide for the continuation of existing streets in adjoining areas and for their proper projection when adjoining land is developed in the future.

(6) All streets in a proposed subdivision shall be so designed that, in the opinion of the Planning Board, they will provide safe vehicular travel while discouraging movement of through traffic, unless this condition is deemed desirable at a given location by the Board.

(7) Where a subdivision abuts or contains an existing collector or arterial street, the Board may require internal access streets, reverse frontage with screen planting contained in a non-access reservation along a property line, deep lots with rear service streets or other such treatment as may be deemed necessary for adequate protection for residential properties and to afford separation of through and local traffic.

(8) Where a subdivision borders on or contains a railroad right-of-way, the Board may require a street approximately parallel to and on each side of such right-of way, at a distance suitable for the appropriate use of the intervening land, as for park purposes in residential districts, or for commercial or industrial purposes in appropriate districts. Such distances shall also be determined with due regard for approach grades and future grade separations.

(9) Sidewalks shall be required in a subdivision when the average lot size is less than 43,560 square feet. The sidewalk shall be five feet wide minimum with a six-inch crushed gravel base and a two-inch binder course overlaid with a one-inch finish course of hot bituminous concrete pavement. All sidewalk construction shall conform to the requirements of the Americans with Disabilities Act. If a horizontal separation between curb and sidewalk is proposed, the area between the two shall be grassed.

(10) Where necessary, in the judgment of the Planning Board, sidewalks and/or rights-of-way (ROW) for pedestrian travel and access may be required in subdivisions when the average lot size is one acre or larger, between subdivisions, or between a subdivision and public property.

(11) In all proposed subdivisions the applicant shall provide for all necessary streetlighting, including poles and light fixtures. Lights will be located where directed by the Planning Board and be of a type, style and intensity acceptable to the Planning Board.

(12) All new streets shall have signs and pavement markings installed in accordance with the Manual of Uniform Traffic Control Devices. It will be the responsibility of the applicant to provide for and install all signs as necessary, including street identification signs.

(13) All proposed streets in which the subbase is within four feet of the estimated seasonal high water table shall have underdrains installed in the subgrade (see Typical Roadway Cross Section for New Construction, Figure No. 1).[1] Test pits will be required along the proposed roadway at two-hundred-foot intervals to verify water table elevation. Where refusal (bedrock) is encountered a two-foot coarse sand subbase shall be placed between bedrock and the road base materials (See Figure No. 1).

[1] Editor's Note: Figure No. 1 is included as an attachment to this chapter.

(14) Vertical granite curbing shall be required on all new roadways, together with a closed drainage system except where it is impractical or impossible to comply with State of New Hampshire requirements concerning stormwater treatment and discharge, or in areas where the Derry Planning Board prefers an uncurbed typical section. Vertical granite curb shall have minimum dimensions of six inches in width by 18 inches in height. Granite curbing shall not be required along the internal edge of culs-de-sac, but the green area within the circle shall be graded two percent (+2%) from the edge of pavement to the center of the cul-de-sac.

[Amended 5-18-2005]

(15) All roadway construction shall conform to the Typical Roadway Cross Section for New Construction (Figure No. 1) as well as Table B, Table of Geometric Standards, attached to these regulations.[2]

[2] Editor's Note: Figure No. 1 and Table B are included as attachments to this chapter.

(16) Driveway curb cuts will be installed prior to the placement of wearing course of hot bituminous asphalt pavement. No driveway locations shall be amended or relocated once the curbing is installed and wearing course is in place. All proposed driveway aprons shall be constructed to a point 40 feet inward from the edge of pavement on all streets at the time of street construction. All driveway aprons shall:

[Amended 5-18-2005; 7-16-2008; 5-18-2016]

(a) All new driveways are to meet the following:

[1] Shall be constructed with a minimum twelve-inch depth of NHDOT Crushed Gravel 304.3 Specification for the entire length.

[2] All loam and organic material shall be removed down to an acceptable subsurface.

[3] Shall have a minimum clear unobstructed width of 12 feet if the driveway is under 150 feet in length or, if the driveway is over 150 feet in length, a minimum clear unobstructed width of 14 feet for the entire length of the driveway.

[4] Shall have an additional clear unobstructed width of two feet on each side.

[5] The vertical clearance shall be a minimum of 13 feet, six inches.

[6] Driveways in excess of 150 feet in length shall provide means for Fire Department apparatus to turn around by either hammerhead or other approved means.

[7] No driveway shall have a grade in excess of a 15%.

(b) All driveway aprons shall:

[1] Slope away from the edge of the road at no less than 3% for open drainage and slope toward the road at no more than 3% in closed drainage subdivisions for a minimum of 10 feet. Maximum grades allowed for next 30 feet are 5% and -5%, respectively.

[2] Be no wider than 24 feet, except that the driveway may be flared at the entrance.

[3] Have a minimum site distance of 200 feet in both directions 10 feet from edge of traveled way.

[4] Be constructed with a minimum twelve-inch depth of NHDOT Crushed Gravel 304.3 Specification for entire length and width of the forty-foot driveway apron.

[5] Include a minimum two-inch thickness of bituminous asphalt base course pavement between edge of pavement and edge of right-of-way (typically 13 feet from edge of roadway pavement).

[6] Be completed along new roadways as part of the road drainage feature as a factor for substantial completion and eligibility of occupancy permits.

[7] Be completed along existing roadways as part of the road drainage feature as a factor for completion of all off-site improvements and eligibility of occupancy permits.

(c) All driveway culverts shall be minimum 15 inches inside diameter HDPE dual-wall pipe a minimum length of 30 feet. Each end shall either have an HDPE flared apron or precast concrete headwall. Minimum cover shall be two feet over the very top of the pipe throughout.

[Added 5-19-2021]

(17) Roadway embankment slopes, including ledge cuts, shall not be steeper than four feet horizontal to one foot vertical and shall be graded, loamed (four inches compacted), and seeded. The Planning Board in special circumstances may permit steeper embankment slopes when the typical 4:1 slope requirement would cause excessive earthwork or impact to wetlands.

[Amended 5-18-2005]

(18) Guardrails shall be provided at all locations where roadway fill embankment slopes are steeper than 4:1. No retaining walls shall be permitted within public rights-of-way.

[Amended 5-18-2005]

B. Horizontal alignment of streets.

(1) Street intersections shall have a minimum center-line offset of 200 feet.

(2) Street intersections shall be designed to intersect at 90º where conditions permit. No intersection shall be permitted where the angle of intersection is less than 80º.

(3) All streets and their intersections shall be designed and constructed with a tangent between successive or reverse curves. The minimum tangent length shall be as indicated in the Table of Geometric Standards attached herewith (Table B).[3]

[3] Editor's Note: Table B is included as an attachment to this chapter.

(4) Whenever a street center line changes direction, a horizontal curve shall be required between successive tangents. The minimum radius for horizontal curves is indicated in the Table of Geometric Standards attached herewith (Table B).

(5) Single access cul-de-sac streets shall not contain more than 30 dwelling units nor be longer than 2,000 feet as measured from the center line of the nearest through street to the center-line radius point of the cul-de-sac. The geometry of proposed culs-de-sac shall conform to the Table of Geometric Standards attached herewith (Table B).

(6) Right-of-way lines at intersections of streets and culs-de-sac shall be rounded with a curve having a minimum radius of 25 feet. A greater radius may be required if requested by the Planning Board.

C. Vertical alignment of streets.

(1) Street grades shall conform to those indicated in the Table of Geometric Standards (Table B).

(2) Vertical curves shall be required at all locations where the change in grade is 1% or greater. Minimum length of vertical curve shall be determined by the formula L=KA, where L = length of vertical curve in feet; A = the algebraic difference in grade in percent; and K is the length of vertical curve per change in A. Values for K are listed in the Table of Geometric Standards (Table B).

(3) At proposed intersections, the cross slope of the intersected street shall be extended a minimum of 10 feet past the typical width of pavement before introducing point of vertical curvature (PVC) of the profile of the intersection street. Further, from that PVC, the maximum grade for 75 feet shall not exceed 2% on arterial and collector roads nor 3% on service roads.

(4) Where, in opinion of the Board, and where it has been demonstrated to the satisfaction of the Board by the subdivider that adherence to the maximum allowable road grade specified in the Table of Geometric Standards (Table B) will cause excessive cuts and fills, a waiver from the above specified maximum grade may be granted, provided:

[Amended 5-18-2005]

(a) The maximum allowable grade is 8%;

(b) The maximum length of such grade, measured between vertical points of intersection (PVI) is 500 feet;

(c) No other such slope greater than 4% occurs within 500 feet measured along the center line of the road from PVI’s; and

(d) The applicant provides written justification to the Planning Board for the design of a street grade greater than 6%.

D. Stopping sight distance.

(1) All streets within a subdivision shall be designed to provide a stopping sight distance at all locations in accordance with the recommendations of the American Association of State Highway and Transportation Officials (AASHTO) as set forth in "A Policy of Geometric Design of Highways and Streets - 1990." An excerpt from Table III-1 of the foregoing document is set forth below for convenience:

	Design Speed (miles per hour)	Minimum Stopping Sight Distance (feet)
	20	125
	25	150
	30	200
	35	225
	40	275
	45	325
	50	400
	55	450

(2) The AASHTO recommendations are based on the height of the driver's eye at 3.5 feet above the road surface and the height of the object to be observed at six inches above the road surface. The six-inch object shall be considered to be in the driveway at a location 10 feet back from the edge of pavement on the street to be accessed, the driver's eye to be in a vehicle approaching the driveway.

(3) Where a new street intersects a proposed or existing street, the new street shall be located such that the foregoing stopping sight distances can be achieved from the point located 10 feet back from the edge of pavement of the intersected street.

[Amended 3-28-2007]

(4) Each lot within the subdivision shall be laid out such that a driveway for access to said lot can be located so that the foregoing stopping sight distances can be achieved from the proposed driveway intersection along the street.

(5) To determine whether the foregoing stopping sight distance requirements have been met, the design plans shall include plans and profiles of proposed and existing streets and driveways. The plans and profiles called for by this subsection shall be drawn to a scale of one inch to 50 feet in the horizontal and one inch to five feet in the vertical.

(6) The applicant shall provide certification from a licensed land surveyor or registered professional engineer that the above requirements have been met on the plans submitted to the Board for approval.

(7) Sight distance easements shall be provided to the Town along horizontal curves and intersections in order to maintain sight distance requirements, where necessary.

§ 170-27 Sewers.

A. Sanitary sewers and manholes shall be located at the center of the traveled lanes on the north and east sides of public right-of-way where possible.

B. All sanitary sewers shall conform to Sections WS 1008.01, WS 1008.02 and WS 1008.03 of the New Hampshire Code of Administrative Rules, latest edition, and to the current Town of Derry Construction Requirements for Sanitary Sewers.

C. The applicant shall provide written copies of all state approvals for the proposed sanitary sewer system.

D. Calculations shall be performed for all new sanitary sewers and shall include flow analysis showing the effect of the proposed sewer on the existing system outside of the area of the subdivision. All sanitary sewers shall be designed based on the New Hampshire Code of Administrative Rules, Standards of Design for Sewerage and Water Treatment Systems, with the following exceptions:

(1) The minimum slope for eight-inch sanitary sewer shall be not less than 0.005 foot per foot;

(2) Sanitary sewer services shall be a minimum of six-inch diameter and shall have a minimum slope of 0.01 foot per foot;

(3) Manholes shall be spaced no more than 300 feet apart; and

(4) Sanitary sewer and manholes shall be constructed of materials as specified in the Town of Derry Construction Requirements for Sanitary Sewers, latest edition.

E. If it is determined that a proposed sanitary sewer may be extended in the future, the future capacity shall be calculated and used to determine the design diameter and slope of sewer mains.

F. Sanitary sewer service stubs shall be constructed to the limits of platted right-of-way at the time of road construction.

§ 170-28 Water mains.

A. Water main shall be located on the south and west sides of public right-of-way where possible.

B. Minimum depth of water mains shall be five feet to prevent damage from freezing.

C. Prior to extending the Town of Derry water system, the applicant shall meet with the Public Works Department to determine the design requirements necessary for a particular project. The applicant shall provide calculations demonstrating that proposed and existing water supply systems meet the requirements of the latest edition of the Town of Derry Construction Requirements for Water Main and have been approved by the Public Works Department.

D. Hydrants shall be located so that the arc of a five-hundred-foot radius from the hydrant extends not less than 200 feet into each lot. Each hydrant must provide adequate flow of water as recommended by the Derry Public Works Department.

E. Proposed community water supply system shall be designed and constructed to Town of Derry Standards, latest edition. Community systems shall be owned by the Town of Derry, unless otherwise approved by the Public Works Department and Planning Board.

F. Water mains and appurtenances shall be constructed of materials as specified in the Town of Derry Construction Requirements for Water Main, latest edition.

G. Water service stubs shall be constructed to the limits of platted public right-of-way at the time of road construction.

§ 170-29 Storm drains.

A. Storm drainage systems shall be designed to control the post-development peak runoff so that it does not exceed predevelopment runoff for the two-year, ten-year, and twenty-five-year, twenty-four-hour storm events. Flood protection works shall be designed for the fifty-year, twenty-four-hour storm event. (Source of extreme precipitation estimates shall be from the Northeast Regional Climate Center.)

[Amended 5-19-2021]

B. The peak rate of discharge of stormwater runoff from the development under post-development conditions shall not exceed that of the pre-development conditions unless it can be demonstrated that no off-site adverse impact will result or appropriate flowage easements have been secured.

C. A development plan shall include provisions to retain stormwater on the site by using the natural flow patterns of the site. Runoff from impervious surfaces shall be treated to achieve 80% removal of total suspended solids and at least 50% removal of both total nitrogen and total phosphorus using appropriate treatment measures, as specified in the NH Stormwater Manual, Volumes 1 and 2, December 2008, as amended, or any subsequent amendment thereto (Refer to Volume 2, page 6, Table 2.1, Summary of Design Criteria, Water Quality Volume, for treatment criteria.), or other equivalent means.

[Added 5-19-2021[1]]

[1] Editor's Note: This ordinance also redesignated former Subsections C through L as Subsections D through M, respectively.

D. The maximum distance of overland flow along roadways shall not exceed 400 feet.

E. Drainage calculations submitted shall, where appropriate, include flow analysis showing the effect of a subdivision on the existing drainage facilities outside of the area of the subdivision. Where the Board anticipates that additional runoff incident to the development of the subdivision will overload an existing downstream drainage facility so that there will be a reasonable likelihood of damage to private property or an increase in the expenditure of public funds, the Board shall not approve the subdivision until adequate provision is made, at the subdivider's expense, for the accommodation of downstream drainage improvements.

F. All calculations used for the design of the storm drainage system shall be by currently recognized best engineering methods and practices and shall be stamped by a licensed professional engineer.

G. Calculations shall be for both pre-development and post-development conditions and shall include the nature and times of concentration, runoff coefficients or curve number, maximum rate of runoff, total amount of runoff, storm sewer and drainage ditch sizing, culvert sizing for all roadway and driveway crossings, retention/detention facilities, and other information as may be required by the Board or Town Engineer.

H. All storm sewers shall be designed to have a minimum flow velocity of two feet per second and a maximum flow velocity of 12 feet per second based on calculated design flow and corresponding to the applicable return frequency design storm.

I. All open ditches and swales shall be designed to have a maximum flow velocity of 10 feet per second. All open ditches and swales shall be designed in accordance with Design of Stable Channels With Flexible Linings, Hydraulic Engineering Circular No. 15, published by the United States Department of Transportation, October 1975.

J. Suitable methods and calculations shall be used to design erosion control methods for use with all storm drainage systems. Such methods shall include but not be limited to headwalls or end sections for all inlets and outlets, bedded riprap for drainage ditches that exceed a flow velocity of 2.5 feet per second, slope mattresses and revegetation.

K. Minimum pipe size shall be 12 inches in diameter for privately maintained storm drainage systems and 15 inches in diameter for publicly maintained storm drainage systems. The minimum depth of cover from the road or ground surface to the crown of the pipe shall be not less than three feet.

L. Storm sewer and appurtenances shall be constructed of materials in accordance with the standards set by the Public Works Department for the Construction of Storm Drains, latest edition. All catch basin grates and frames shall be heavy-duty gray cast iron meeting ASTM A48 Class 30 (American Foundry) with a twenty-four-inch by twenty-four-inch opening a two-inch square opening pattern on grate, unless otherwise approved by the Planning Board. Polyethylene liners shall be installed in all proposed catch basins. All grates or hatches at outlet control devices shall be fabricated from stainless steel or hot-dipped galvanized steel (ASTM A123/A123M).

[Amended 5-18-2005; 6-18-2008]

M. No underground stormwater collection basins or infiltration systems shall be permitted.

[Added 6-18-2008]

N. Salt storage areas shall be covered and loading/off-loading areas shall be designed and maintained in accordance with NHDES published guidance such that no untreated discharge to receiving waters results. Snow storage areas shall be located in accordance with NHDES published guidance such that no direct untreated discharges to receiving waters are possible from the storage site. Runoff from snow and salt storage areas shall enter treatment areas as specified above before being discharged to receiving waters or allowed to infiltrate into the groundwater.

[Added 5-19-2021]

O. All plans shall note that "Snow and ice removal shall be performed by a Green Sno-Pro Certified contractor following best management practices for the application of de-icing materials."

[Added 5-19-2021]

§ 170-30 Fire protection.

[Amended 3-28-2007; 6-18-2008; 4-2-2014]

A. Fire protection options.

(1) Fire hydrants. Any development occurring within 1,000 linear feet, as measured along the course of a public or private street, access drive or right-of-way of an existing public water main, shall extend the public water system to provide fire hydrants to within 500 feet of any proposed lot within the development for fire protection purposes. The measurement shall be from the fire hydrant to the access drive of the building lot All water mains and fire hydrants shall be installed in accordance with the requirements of the Public Works Department.

(2) In the event that the public water system owner deems the extension of the water main technically unfeasible, the developer will be required to install fire cisterns or the developer may have an option to install individual residential sprinkler systems in lieu of fire cisterns.

(3) Fire cisterns. Any development occurring outside the public water system by a distance greater than 1,000 feet may provide water for fire protection purposes through the use of fire cisterns. The cistern shall be located no further than 1,000 linear feet from the access drive to any building lot within the development. Fire cisterns shall meet the specification and be installed in accordance with the requirements of the Derry Fire Department. The developer will be required to present a statement to the Planning Department from the Fire Department which indicates compliance with this provision.

(4) Residential sprinkler systems. In residential developments, when the developer has chosen to install residential sprinkler systems in lieu of fire cisterns, those systems shall be installed in accordance with the most recent edition of Standards 13D or 13R of the National Fire Protection Association. The sprinkler system must be reviewed and approved by the Fire Department prior to installation and tested by the Fire Department prior to issuance of certificate of occupancy.

§ 170-31 Other utilities.

A. In all proposed subdivisions, electric, telephone, cable, and other utility distribution lines shall be installed underground per specifications of the utility companies involved.

B. Appropriate easements, if any, required for proper utility construction and maintenance shall be platted and conveyed as part of subdivision design.

C. Utility construction shall be completed in a manner which will not interfere with proper roadside drainage.

D. Detailed plans for all underground transmission or utility lines shall be supplied to the Public Works Department prior to installation, and record drawings, sealed by a licensed professional engineer or licensed land surveyor, shall be supplied to the Public Works Department and utility companies following installation and prior to release of performance guarantees.

§ 170-32 Special flood hazard areas.

A. All subdivision proposals which contain lands designated as "special flood hazard area" by the Federal Emergency Management Agency (FEMA) in its Flood Insurance Study for Rockingham County, NH, together with the associated Flood Insurance Rate Maps (FIRM) dated May 17, 2005, shall meet the requirements of this section.

[Amended 12-14-2011]

B. The Planning Board shall review the proposed development to assure that all necessary permits have been received from those governmental agencies from which approval is required by federal or state law, including Section 404 of the Federal Water Pollution Control Act, Amendments of 1972, 33 U.S.C. § 1334.

C. The Planning Board shall require that all subdivision proposals include within such proposals base flood elevation data, if applicable.

D. Sufficient evidence (construction, drawings, grading and land treatment plans) shall be submitted so as to allow a determination that:

(1) All such proposals are consistent with the need to minimize flood hazards;

(2) All public utilities and facilities, such as sewer, gas, electrical, and water systems, are located and constructed to minimize or eliminate flood damage; and

(3) Adequate drainage is provided so as to reduce exposure to flood hazards.

E. In order to obtain the approval of the Planning Board, the applicant must affirmatively demonstrate to the Board, by a preponderance of the credible evidence presented at a public meeting or meetings, that all the requirements of this section have been met and that the procedures set forth in these regulations have been followed.

F. No development which requires approval by the Board will be permitted in the Conservation Corridor Overlay District (as defined in Chapter 165, Zoning) unless the applicant has applied for and received a special exception under the provisions of Article IX, § 165-74 of Chapter 165, Zoning, and has demonstrated that there will be no impairment of the absorptive capacity of the wetlands within the Conservation Corridor Overlay District, as defined by Chapter 165, Zoning, that floodwater elevations will not be increased, and that there will be no harm caused to wildlife.

§ 170-33 Off-site improvements.

If the Board determines that the proposed development creates the need for off-site improvements, all or part of which are rationally related to or occasioned by the proposed development, or which will require an excessive expenditure of public funds in order to provide the same, the Planning Board may impose the requirement that the applicant install or pay for all or part of such off-site improvements.

A. When imposing such requirement, the Board shall consider the degree to which the proposed development is benefited by such off-site improvements.

B. Such deliberations shall include whether other properties would also benefit from the upgrading of such off-site improvements. In such cases the Board shall determine the amount to be paid by the applicant, taking into consideration the following:

(1) The character of the area;

(2) The extent that the general and/or other public or private property will be benefited by the off-site improvement; and

(3) Any other factor that the Board deems appropriate to establish a rational connection to the needs created by the development to the amount to be paid by the applicant.