A.

Establishment. The High Groundwater Table and Impervious Layer Overlay District (High Groundwater Overlay) is hereby established and may be referred to hereafter as the "High Groundwater Overlay." This overlay district encompasses specific areas of the town as shown on the map entitled "Zoning Map Overlay District Related to Protection of Critical Lands Containing Freshwater Wetlands, High Groundwater Table, and/or Shallow Impervious Layer" dated August 2007 and attached to the zoning ordinance.

B.

Findings. The High Groundwater Overlay encompasses areas where nonconforming lots predominate, no public sewer and water are available, and the hydrogeologic conditions provide considerable constraint to development. These conditions require special design approaches and/or infrastructure in order to protect individual homeowners, neighborhoods, and Jamestown's water resources.

C.

Applicability. The following activities are subject to the procedures, review, and standards within the High Groundwater Overlay only where the activity is proposed on a lot that is less than 40,000 square feet:

1)

Any construction activity that results in the development of new impervious cover.

2)

Any construction activity that results in the replacement or expansion of existing impervious cover.

3)

Excavation, mining, dredging, filling, or grading that involves the movement of over 200 cubic feet of soil.

D.

Sub-districts. The High Groundwater Overlay is divided into two sub-districts as follows:

1)

Sub-district "A" consists of those lots where:

a)

The seasonal high groundwater table is less than or equal to 18 inches below the original grade; or

b)

The impervious layer is less than or equal to 42 inches below the original grade.

2)

Sub-district "B" consists of those lots where:

a)

The seasonal high groundwater table is greater than 18 inches and equal to or less than 48 inches below original grade; or

b)

The impervious layer is greater than 42 inches and up to and including 60 inches below the original grade.

E.

Determination of sub-district.

1)

Presumption of sub-district A. Absent the evidence required to make a determination of which sub-district applies to a particular lot, the town shall presume sub-district A applies with eight percent maximum impervious surface coverage (see section 82-800 H, Impervious cover, below). An applicant may enter into development permitting procedures voluntarily with this presumption.

2)

Evidence. The decision as to whether a particular lot is located in either sub-district A or sub-district B shall be made by the zoning enforcement officer based on the field observation required (subsection E.4). A submission of evidence to the zoning enforcement officer shall include all of the results of examination or testing conducted on the lot and shall be accompanied by a written representation by the owner/applicant or project representative that no such results are being withheld.

3)

Previous determination. Where a property owner or the town can produce records of a previous determination made by the town, that determination may be used provided there is a record of the field observations used to make that determination.

4)

Field observation required. Soil evaluations verified by a RIDEM Class IV soil evaluator are required to determine the applicable sub-district.

a)

Where a new OWTS is proposed, the applicant shall provide record of the two soil evaluations associated with the OWTS, as required by RIDEM.

b)

Where an OWTS already exists, and a new OWTS is not proposed, records of the soil evaluations from the original state approval shall be submitted to the town.

c)

Where a new structure is proposed on a lot the applicant shall provide a single soil evaluation in the area of each proposed structure's footprint in addition to test hole information associated with the existing or proposed OWTS.

5)

Determination. The zoning enforcement officer shall make a determination of which sub-district applies based on the following:

a)

If any of the soil evaluations show evidence meeting at least one of the sub-district A criteria, then the lot lies in sub-district A;

b)

If none of the criteria for sub-district A are met in any of the soil evaluations, and at least one of the criteria for sub-district B is met in any of the soil evaluations, then the lot lies in sub-district B;

c)

If none of the soil evaluations meets either the sub-district A or the sub-district B criteria, then the lot is not subject to the standards promulgated in the High Groundwater Overlay.

F.

Permit review.

1)

Construction, reconstruction, or renovation of structures or other new impervious surface coverage 200 square feet or greater in sub-district A shall be reviewed first by the Planning Commission through as a recommendation to the Zoning Board of Review. The activities shall subsequently require a special use permit from the zoning board of review. The planning commission recommendation shall be advisory to the special use permit application reviewed by the zoning board of review.

2)

A one-time construction, reconstruction, or renovation of structures or other new impervious surface coverage less than 200 square feet in sub-district A shall be reviewed under administrative development plan review. Any additional construction, reconstruction, or renovation to the subject lot shall comply with the requirements of section 82-800 as development over 200 square feet or greater.

3)

Activities subject to review in sub-district B shall be reviewed under administrative development plan review.

4)

The town may engage one or more professionals as deemed necessary by the town, at the expense of the applicant, to assist with the review of applications at a reasonable cost.

G.

Prohibitions.

1)

The installation of subsurface drains designed to intercept and lower the groundwater table for the installation of an OWTS.

2)

Any proposed new or expanded basement and/or the bottom of any structure's slab, not including pilings/footings that is less than 12 inches above the seasonal high groundwater table is prohibited. In-ground swimming pools are prohibited in sub-district A.

H.

Impervious cover. Lots in sub-district A and sub-district B shall have limitations on the amount of impervious cover that may be installed in accordance with the following provisions:

1)

A lot in sub-district A shall be limited in accordance with the following chart and associated provisions:

a)

Where the examination and/or testing of multiple areas of a lot yield different results as to the water table and/or impervious layer, the percent of maximum impervious cover for the lot shall be determined on the most restrictive results in both categories.

b)

Freshwater wetlands shall be subtracted from total lot size prior to calculating maximum impervious cover.

2)

In sub-district B, no lot shall have more than 15 percent impervious cover.

3)

Impervious surface coverage on a structure shall be calculated at the exterior walls with an ordinary roof projection of 12 inches. Any roof projection beyond 12 inches will count toward the impervious surface coverage.

I.

Performance standards. Activities subject to review under the provisions of the High Groundwater Overlay shall comply with the following development standards as applicable. Applicants may request relief from these standards through an application for a special use permit from the zoning board of review.

1)

All existing OWTS shall be in good working order. Within sub-district A, all existing OWTS will require a flow test conducted by a licensed maintenance provider. Within sub-district B, for any project involving an addition of 400 square feet or more to a building or structure, all existing OWTS will require a flow test conducted by a licensed maintenance provider. In both sub-Districts A and B, a maintenance report for an existing OWTS certified by a licensed maintenance provider and completed within the past 12 months may be submitted for any flow test required above.

2)

All OWTS and wells shall be located on the same lot of the residence to which they are connected. All new OWTS and OWTS requiring major repair shall be approved by RIDEM and shall be designed for advanced reduction of nitrogen. Where necessary for the protection of public health, as defined by RIDEM, the systems shall also be designed for enhanced pathogen removal. OWTS shall use approved technologies listed by the RIDEM and shall be capable of achieving current RIDEM performance standards for denitrification and/or pathogen removal.

3)

Applications shall provide a stormwater best management practice capable of storing, on the subject site, the increased volume of runoff resulting from development of the site.

a)

The minimum storage volume shall be the difference between the pre-development and post-development runoff volumes using the ten-year, 24-hour, Type III storm event.

b)

Stormwater mitigation and water quality treatment practices shall be designed in accordance with the Rhode Island Stormwater Design and Installation Standards Manual, most current edition.

For the purposes of this calculation the following table will be used:

4)

There shall be a 15-foot separation between a leachfield and the edge of any stormwater infiltration system.

5)

Proposals must comply with the Jamestown Soil Erosion and Sediment Control Ordinance contained in the Code of Ordinances, chapter 22, article V, division 2.

6)

Operation and maintenance requirements of any designed and approved stormwater system shall be recorded with the final approval from the zoning board.

J.

Special use permit criteria. The proposal shall incorporate, to the greatest extent possible, the following design criteria and explanation of such shall be provided as a narrative to the proposal where practical. Where a special use permit is required pursuant to the provisions of the High Groundwater Overlay, the zoning board of review may approve, deny, or approve with conditions based on the standards and criteria within this section of the zoning ordinance.

1)

General criteria.

a)

The proposed use and site design are appropriate to the natural characteristics of the land, including its suitability for use based on soil characteristics, geology, topography and susceptibility to surface and groundwater pollution.

b)

The proposal preserves the values of unique or valuable natural resources and features.

c)

The proposal is appropriate to the availability and capacity of existing public and/or private services and facilities.

d)

The proposal is consistent with the goals and pattern of land use contained in the Jamestown Comprehensive Plan.

e)

Site design measures protect the island's vulnerable and limited water supplies by maintaining maximum groundwater recharge of rainfall and treated wastewater to replenish drinking water supplies and avoid salt water intrusion.

f)

The site design approach is consistent with the need to prevent further impacts and restore impaired areas where intense development and water use, in combination with limited land development suitability, have resulted in localized flooding, incidents of groundwater contamination, low well yields, and salt water intrusion.

2)

Subsurface structures.

a)

The design of the subsurface structures shall minimize the problems and hazards created by the seasonal high groundwater table and/or impervious layer and result in the least grading, filling, or other disturbance to the site and to any wetland buffer as possible.

b)

The seasonal high groundwater table will not damage, interfere or reduce the potential for the proper functioning of the subsurface structure.

c)

The subsurface structure will not pose any threat to public health or safety or to the water resources of the town, including groundwater.

3)

On-site wastewater treatment systems.

a)

All proposals relating to the installation of an OWTS shall ensure that the system, once in use, will not pose a threat to the public health and safety nor cause unreasonable degradation of ground or surface water quality, including adverse effects due to cumulative impact.

b)

All proposals relating to the installation of an OWTS shall demonstrate that the design, siting and selection of technologies for the treatment and dispersal units are the most appropriate for the site.

c)

All proposals relating to the installation of an OWTS shall demonstrate that the project has been designed so as to minimize combined impacts related to the OWTS, stormwater runoff, and potential disturbances to wetland buffers.

4)

Stormwater management.

a)

Stormwater runoff control measures will minimize site disturbance, maximize nonstructural controls, and will not adversely affect subsurface flow of groundwater.

b)

The proposed site improvements minimize fill and grading, and maintain, to the greatest extent possible, the existing overland flow of runoff from the site to surrounding areas.

c)

All stormwater management measures will maintain the water quality function of wetland buffers and avoid any encroachment that might impair the wetland's pollutant removal capacity. Proposed measures will not direct channelized flow to the wetland, reduce subsurface flow through the buffer, increase sedimentation, reduce shade cover, or include any alteration that would result in fluctuating water levels that negatively impact sensitive habitat.

K.

Variances for prohibited uses in sub-district A.

1)

Applicants proposing uses prohibited pursuant to [sub]section G hereof shall, after development plan review by the planning commission and recommendation to the zoning board, be required to obtain a use variance pursuant to article 3 hereof. In addition to the standards contained in article 3 hereof, all applicants shall demonstrate that the proposal meets, to the greatest extent possible, all of the performance standards contained in subsections I and all of the criteria in subsection J hereof.

2)

Applicants shall file a development plan with the building official containing the information listed on the application available in the office of the environmental scientist, public works department.

(Ord. of 2-3-2025(1), § 1(Exh. A))

A.

Statement of purpose. The purpose of this chapter is to ensure public safety; minimize hazards to persons and property from flooding, to protect watercourses from encroachment, and to maintain the capability of floodplains to retain and carry off floodwaters. The Town of Jamestown elects to comply with the requirements of the National Flood Insurance Act of 1968 (P.L. 90-488, as amended).

B.

Applicability. The special flood hazard areas are herein established as a floodplain overlay district. The district includes all special flood hazard areas within the Town of Jamestown designated as Zone A, AE, AH, AO, A99, V, or VE on the Newport County Flood Insurance Rate Map (FIRM) and Digital FIRM issued by the Federal Emergency Management Agency (FEMA) for the administration of the National Flood Insurance Program. The map panels of the Newport County FIRM that are wholly or partially within the Town of Jamestown are panel numbers 44005C0059J, 44005C0067J, 44005C0069J, 44005C0078J, 44005C0088J, 44005C0157J, 44005C0159J and 44005C0176J dated September 4, 2013 (as periodically amended). The exact boundaries of the district may be defined by the 100-year base flood elevations shown on the FIRM and further defined by the Newport County Flood Insurance Study (FIS) report dated September 4, 2013. The FIRM and FIS report and any revisions thereto are incorporated herein by reference and are on file with the town clerk, planning commission, and building official.

C.

Administrative Provisions.

Use permit. All proposed construction or other development within a special flood hazard area shall require a permit.

If the construction or other development within a special flood hazard area is not covered by a building or other approved permit application, a flood hazard development permit shall be required. The application for a flood hazard development permit shall be submitted to the building official and shall include:

1)

The name and address of the applicant;

2)

An address or a map indicating the location of the construction site;

3)

A site plan showing location of existing and proposed structures, sewage disposal facilities, water supply facilities, areas to be cut and filled, and the dimensions of the lot;

4)

A statement of the intended use of the structure;

5)

A statement as to the type of sewage system proposed;

6)

Specification of dimensions of the proposed structures;

7)

The specific datum used for all elevations;

8)

The elevation (in relation to mean sea level) of the lowest floor, including basement, and if the lowest floor is below grade on one or more sides, the elevation of the floor immediately above;

9)

Base flood elevation data for all new, relocated or substantially improved structures;

10)

The elevation (in relation to mean sea level) to which the structure will be floodproofed;

11)

The description of the extent to which any watercourse will be altered or relocated as a result of the proposed development.

Prior to the issuance of a building or development permit, the applicant shall submit evidence that all necessary permits and approvals have been received from all government agencies from which approval is required by federal or state law.

A permit fee (based on the cost of the construction) may be required to be paid to the Town of Jamestown and a copy of a receipt for the same shall accompany the application. An additional fee may be charged if the code enforcement officer and/or board of appeals needs the assistance of a professional engineer.

Disclaimer of liability. The degree of flood protection required by the ordinance is considered reasonable but does not imply total flood protection.

Severability. If any section, provision, or portion of this chapter is adjudged unconstitutional or invalid by a court, the remainder of the ordinance shall not be affected.

Abrogation and greater restriction. This chapter shall not in any way impair/remove the necessity of compliance with any other applicable laws, ordinances, regulations, etc. Where this chapter imposes a greater restriction, the provisions of this chapter shall control.

D.

Notification of watercourse alteration. In a riverine situation, the building official shall notify the following of any alteration or relocation of a watercourse:

• Adjacent communities

• Bordering states (optional)

• NFIP state coordinator

• Rhode Island Emergency Management Agency

645 New London Avenue

Cranston, RI 02920

• NFIP Program Specialist

Federal Emergency Management Agency, Region I

99 High Street, 6th Floor

Boston, MA 02110

The carrying capacity of the altered or relocated watercourse shall be maintained.

E.

Use regulations.

1)

Reference to existing regulations. The special flood hazard areas are established as a floodplain overlay district. All development in the district, including structural and non-structural activities, whether permitted by right or by special permit must be in compliance with the following:

• Rhode Island State Building Code (SBC-1-2007 as established under G.L. 1956, ch. 23-27.3);

• Coastal Resources Management Program, Coastal Resource Management Council (G.L. 1956, ch. 46-23)

• Freshwater Wetlands Act, Department of Environmental Management (G.L. 1956, § 46-23-6)

• Minimum Standards Related to Individual Sewage Disposal Systems, Department of Environmental Management (G.L. 1956, ch. 46-12)

Any variances from the provisions and requirements of the above referenced state regulations may only be granted in accordance with the required variance procedures of these state regulations.

2)

Other use regulations.

a)

In Zones A1-30 and AE, along watercourses that have a regulatory floodway designated on the Town of Jamestown FIRM or flood boundary and floodway map encroachments are prohibited in the regulatory floodway which would result in any increase in flood levels within the community during the occurrence of the base flood discharge.

b)

All subdivision proposals must be designed to assure that:

• Such proposals minimize flood damage;

• All public utilities and facilities are located and constructed to minimize or eliminate flood damage; and

• Adequate drainage is provided to reduce exposure to flood hazards.

c)

Detached accessory structures in Zones A, AE, A1-30, AO, and AH (i.e., garages, sheds) do not have to meet the elevation or dry flood-proofing requirement if the following standards are met:

• The structure is no more than 100 square feet in size and has a value less than $1,000.00.

• The structure has unfinished interiors and must not be used for human habitation. An apartment, office or other finished space over a detached garage is considered human habitation and would require the structure to be elevated.

• The structure is used solely for parking of vehicles and/or limited storage.

• The accessory must be wet floodproofed and designed to allow for the automatic entry and exit of flood water.

• The accessory structure shall be firmly anchored to prevent flotation, collapse and lateral movement.

• Service facilities such as electrical, mechanical and heating equipment must be elevated or floodproofed to or above the base flood elevation.

• The structure must not increase the flood levels in the floodway.

d)

Existing contour intervals of site and elevations of existing structures must be included on the plan proposal.

3)

Base flood elevation and floodway data.

a)

Floodway data. In Zones A, A1-30, and AE, along watercourses that have not had a regulatory floodway designated, the best available federal, state, local, or other floodway data shall be used to prohibit encroachments in floodways which would result in any increase in flood levels within the community during the occurrence of the base flood discharge.

b)

Base flood elevation data. Base flood elevation data is required for subdivision proposals or other developments greater than 50 lots or five acres, whichever is the lesser, within unnumbered A zones.

c)

Base flood elevations in A zones. In the absence of FEMA BFE data and floodway data, the best available federal, state, local, or other BFE or floodway data shall be used as the basis for elevating residential and non-residential structures to or above the base flood level and for floodproofing non-residential structures to or above the base flood level.

(Ord. of 2-3-2025(1), § 1(Exh. A))

A.

Per P.L. 2015, ch. 218, § 3, G.L. 1956, § 45-24-30(c), 250-RICR-150-15-3, the Rules and Regulations Governing the Administration and Enforcement of the Freshwater Wetlands Act (the "DEM Wetlands Regulations"), and 650-RICR-20-00-9, the Rules and Regulations Governing the Protection and Management of Freshwater Wetlands in the Vicinity of the Coast (the "CRMC Wetlands Regulations"), Rhode Island cities and towns are prohibited from applying requirements pertaining to wetland buffers and onsite wastewater treatment system setbacks to development applications submitted to a municipality after July 1, 2022, the effective date of said state regulations. Applications made on or after this date shall comply with the DEM Regulations and/or the CRMC Wetlands Regulations. Applications made prior to this date remain subject to the standards of this section 82-802.

B.

Unless authorized and permitted by the Rhode Island Department of Environmental Management Office (RIDEM) of Water Resources through the RIDEM permitting process, no sewage disposal trench, drain field, bottomless effluent filter, nor any component of a system designed to leach liquid wastes into the soil shall be located within 150 feet from a freshwater wetland edge, excluding the state designated perimeter wetland and riverbank wetland. For the purposes of this section, the freshwater wetland edge shall be the RIDEM verified edge of wetland. If the wetland is not on the subject property and in the absence of RIDEM verified wetland mapping on the adjacent property, then best available mapping should be utilized, as determined by the building official.

C.

Requests for dimensional variances. Application may be made to the zoning board of review for a dimensional variance seeking relief from the setback requirement contained in this section. All such applications shall be first referred to the planning commission for development plan review for an advisory opinion, per the requirements for development plan outlined in article 10. However, where the applicant is requesting less than 25 percent relief the town planner shall administratively process the application for recommendation to the zoning board of review. The planning commission and/or town planner and the zoning board shall consider the following minimum development standards:

In addition to the standards contained elsewhere in this section and in article 3 hereof the applicant shall demonstrate that the implementation of the proposal:

1)

Will not degrade the quality of groundwater or any wetland or surface water body, either directly or indirectly, on site or off site;

2)

Will result in the least site disturbance and removal of vegetation as possible, every attempt shall be made to site the wastewater treatment system and the associated dwelling as far as possible from the wetland edge;

3)

Will not obstruct floodways or reduce the net capacity of the site to retain floodwaters;

4)

Will not cause any sedimentation of wetlands, and will include all necessary erosion and sediment control measures; plans for erosion and sediment control and stormwater management shall be completed which meets standard requirements for such plans and also includes:

a)

The limits of disturbance during construction including areas to be cleared and/or graded, construction easements, temporary stockpiles and material/equipment storage areas, and protection of individual trees and groups of trees to avoid construction injury by fencing off trees at the drip line. In critical areas the limits of disturbance will be fenced off in the field.

b)

A plan for revegetation, stamped by a landscape architect of wetland buffers, slopes and erodible areas.

5)

Will not reduce the capacity of any wetland to absorb pollutants;

6)

Will not degrade the recreational or educational value of any wetland or water body;

7)

Will not reduce the capacity of any wetland to recharge groundwater; and

8)

Will not degrade the value of any wetland or water body as a spawning ground or nursery for fish and shellfish, or habitat for wildlife and wildfowl. In considering the above, the cumulative impact of all land within a 500-foot radius must be addressed. Where vernal pools are found, the applicant will identify mitigating measures to protect such habitat.

(Ord. of 2-3-2025(1), § 1(Exh. A))

Exempted from the provisions of this section providing for development standards in an RR-200 zoning districts are the following uses:

A.

New single-family residential uses and their customary accessory uses on lots of 200,000 square feet area or greater;

B.

Agricultural use of lands when operated in accordance with a farm conservation plan approved by the Eastern Rhode Island Conservation District or when it is determined by the district that such use will not reduce the quality of a public water supply;

C.

Existing single-family dwellings and their customary accessory uses.

(Ord. of 2-3-2025(1), § 1(Exh. A))

Within any RR-200 zoning district, special standards of site development shall apply in order to protect surface water reservoirs or their tributary streams and/or groundwater aquifers. Prior to the issuance of any building permit within an RR-200 zoning district, the zoning enforcement officer shall require a development plan to be filed, at a suitable scale. On top of the requirements for development plan review in article 10 and the town's subdivision and land development regulations, the development plan shall show the following information:

• Property boundary lines, with area and dimensions of the property to be developed;

• Vicinity plan showing adjacent or nearby properties, uses, wetlands, streams or surface water reservoirs;

• Topography map of the property;

• Soils map of the property.

The applicant for a building permit shall also indicate proposed uses and development. For the purposes of this section, development shall be defined as any manmade change to improved or unimproved real estate, including, but not limited to, buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations upon the lot.

The applicant shall be required to show, to the extent necessary, the likely impact which the proposed development will have upon surface and subsurface water quality. In particular, the following issues shall be addressed:

• Methods to be used during construction to control soil erosion and sedimentation of wetlands;

• Provision for disposal of stormwater runoff, including an estimate of the existing and proposed release rates, drainage system and stormwater detention measures (if proposed);

• Sewage disposal methods, including an evaluation of the impacts of disposal methods on surface water, soils and vegetation;

• Amount of paved and other impervious surfaces and measures for the preservation of vegetation, impervious surfaces and groundwater infiltration;

• If storage of toxic substances is proposed, methods for prevention of contamination of surface and subsurface water.

(Ord. of 2-3-2025(1), § 1(Exh. A))

Upon receipt of an application for development within an RR-200 zoning district, the zoning enforcement officer shall transmit to the planning commission, who shall review said [the] information and file, within 45 days of receipt thereof, an advisory report to the zoning enforcement officer, together with any recommendations thereon.

(Ord. of 2-3-2025(1), § 1(Exh. A))

At a minimum, the following standards of development shall be required:

A.

Erosion and sediment control measures shall be designed to meet at least the minimum standards and specifications of the Rhode Island Soil Erosion and Sediment Control Handbook, U.S. Department of Agriculture, Soil Conservation Service, and Rhode Island State Conservation Committee, 1989;

B.

All buildings and parking areas shall be set back at least 300 feet from any reservoir, or tributary stream used to supply or transport public water supplies;

C.

Driveways, parking lots, and other impervious surfaces are minimized, or specified as porous surfaces, such as crushed stone, spaced paving block, etc.;

D.

Permanent vegetation cover is provided in unpaved areas; temporary vegetation is provided in areas which will remain open for more than six months;

E.

All earth changes shall be designed, constructed, and completed in such manner so that the exposed area of any disturbed level shall be limited to the shortest possible period of time;

F.

Stormwater storage and/or retention facilities are provided to prevent significant increases in volume and rate beyond existing conditions.

(Ord. of 2-3-2025(1), § 1(Exh. A))