[HISTORY: Adopted by the Town Council of the Town of Milton 6-22-2015 by Ord. No. 2015-009. Amendments noted where applicable.]
GENERAL REFERENCES
Building construction — See Ch. 85.
Abandoned excavations — See Ch. 116.
Floodplain management — See Ch. 125.
Sewers — See Ch. 170.
Streets and sidewalks — See Ch. 183.
Subdivision of land — See Ch. 188.
Water — See Ch. 215.
Zoning — See Ch. 220.
A. 
The purpose of this chapter is to ensure the protection of the public drinking water supply from contamination. The Town of Milton herein adopts the overlay maps delineating, as source water protection areas: wellhead protection and excellent groundwater recharge potential areas. To ensure the protection of these drinking water supplies, this chapter establishes a zoning overlay to be known as the "Source Water Protection Overlay." The purpose of the Source Water Protection Overlay is to protect public health and safety by minimizing contamination of aquifers, preserving, and protecting existing and potential sources of drinking water supplies. It is the intent to accomplish this through both public education and public cooperation, as well as by creating appropriate land use regulations that may be imposed in addition to those currently imposed by existing zoning districts or other state and county regulations.
B. 
The Source Water Protection Overlay is superimposed on current zoning districts. It shall apply to all new construction, redevelopment, or expansion of existing buildings and new or expanded uses. Applicable activities or uses allowed in a portion of one of the underlying zoning districts that fall within the Source Water Protection Overlay must additionally comply with the requirements of this district. Uses prohibited in the underlying zoning districts shall not be permitted in the Source Water Protection Overlay District.
This section defines words, terms, and phrases found in this chapter.
ABOVEGROUND STORAGE TANK (AST)
A single containment vessel greater than 250 gallons, as defined in the Delaware Regulations Governing Aboveground Storage Tanks, dated February 11, 2005. ASTs with a storage capacity greater than 12,499 gallons containing petroleum or hazardous substances, and ASTs with a storage capacity greater than 39,999 gallons containing diesel, heating fuel or kerosene, are subject to the design, construction, operation, and maintenance requirements of the Delaware AST Regulations.
APPLICANT
A person, firm, or government agency that executes the necessary forms to obtain approval or a permit for any zoning, subdivision, land development, building, land disturbance, or other activity regulated.
AQUIFER
A geological formation, group of formations or part of a formation, composed of rock, sand, or gravel, capable of storing and yielding groundwater to wells.
CERCLA HAZARDOUS SUBSTANCES
Those substances specifically designated as hazardous under the Comprehensive Environmental Response. Compensation, and Liability Act (CERCLA), otherwise known as the "Superfund Law," or those substances identified under other laws. In all, the Superfund Law includes references to four other laws to designate more than 800 substances as hazardous and identify many more as potentially hazardous due to their characteristics and the circumstances of their release. See: http://www.epa.gov/superfund/programs/er/hazsubs/cercsubs.htm.
CONTAMINATION
Any physical, chemical, biological, or radiological substance that enters the hydrological cycle through human action and may cause a deleterious effect on groundwater resources; it shall include but is not limited to hazardous waste, limiting nutrients, and sanitary sewage.
DELINEATION
The process of defining and/or mapping a boundary that approximates the areas that contribute water to a particular water source used as a public water supply.
ENVIRONMENTAL IMPACT ASSESSMENT REPORT (EIAR)
A report required by this chapter that assesses the environmental characteristics of a source water protection area and determines what effects or impacts will result if the area is altered or disturbed by a proposed action that would increase impervious cover beyond the recommended 20% threshold.
EXCELLENT GROUNDWATER RECHARGE POTENTIAL AREA
Those areas with high percentages of sand and gravel that have "excellent" potential for recharge as determined through a stack unit mapping analysis delineated by the Delaware Geological Survey and presented in the Report of Investigations No. 66, Ground-water Recharge Potential Mapping in Kent and Sussex Counties, Delaware, Geological Survey, 2004.
GEOLOGIST
An individual who is registered in the State of Delaware to practice the profession of geology.
GROUNDWATER
The water contained in interconnected pores located below the water table in an unconfined aquifer or located in a confined aquifer.
HAZARDOUS SUBSTANCE UST SYSTEM
An underground storage tank system that contains a hazardous substance defined in Section 101(14) of the CERCLA (but not including any substance regulated as a hazardous waste under RCRA, Subtitle C), or any mixture of such substances and petroleum, and which is not a petroleum UST system.
HAZARDOUS WASTE
A solid waste, or combination of solid wastes, which, because of its quantity, concentration, or physical, chemical, or infectious characteristics, may cause or significantly contribute to an increase in mortality or an increase in serious irreversible or incapacitating irreversible illness or pose a substantial present or potential hazard to human health or the environment when improperly treated, stored, transported, or disposed of, or otherwise managed, without limitation; included within this definition are those hazardous wastes described in Sections 261.31, 261.32, and 261.33 of the Delaware Regulations Governing Hazardous Waste.
IMPERVIOUS COVER
Surfaces providing negligible infiltration, such as pavement, buildings, recreation facilities (e.g., tennis courts, swimming pools, etc.), and covered driveways.
NATURAL CONDITION
Open space that is essentially unimproved and set aside, dedicated, designated, or reserved for public or private use.
NONCONFORMING USE
An existing use of a lot or a building that was legal at the time of its creation that is not permitted by this chapter in the district in which it is located.
ON-SITE WASTEWATER TREATMENT AND DISPOSAL SYSTEM
Any conventional or alternative wastewater treatment and disposal systems installed or proposed to be installed on land of the owner or on other land to which the owner has the legal right to install the system.
PASSIVE RECREATION
Recreation that involves existing natural resources and has a minimal impact because it does not require the alteration of existing topography. Such passive recreation shall include but not be limited to nonmotorized vehicles, hiking, bicycling, picnicking, and bird-watching.
PUBLIC DRINKING WATER SYSTEM
A community, noncommunity, or nontransient noncommunity water system, which provides piped water to the public for human consumption. The system must have at least 15 service connections or regularly serve at least 25 individuals daily for at least 60 days.
PUBLIC WATER SUPPLY WELL
Any well from which the water is used to serve a community water system by Section 22.146 (Public Water Systems) in the Delaware State Regulations Governing Public Drinking Water Systems.
REDEVELOPMENT
Any proposed expansion, addition, or major facade change to an existing building, structure, or parking facility.
RUNOFF
That portion of precipitation or snow melt that has not evaporated or infiltrated into the soil but flows on land or impervious surfaces.
SANITARY LANDFILL
A land site at which solid waste is deposited on or into the land as fill for the purpose of permanent disposal, except that it will not include any facility that has been approved for the disposal of hazardous waste under the Delaware Regulations Governing Hazardous Waste.
SITE PLAN APPROVAL
A process for the review and approval of a development plan prior to the issuance of a development as outlined in Chapter 220, Zoning, of the Milton Town Code.
SOURCE WATER
Any aquifer from which water is drawn, either periodically or continuously, by a public water system.
SOURCE WATER ASSESSMENT AREA
The area delineated by the DNREC Source Water Assessment and Protection Program that contributes water to a public water supply system.
SOURCE WATER ASSESSMENT PLAN
The October 1999 US EPA approved plan for evaluating the sources of public drinking water in Delaware for their vulnerability and susceptibility to contamination.
SOURCE WATER ASSESSMENT REPORT (SWAP)
The identification and evaluation of the sources of water within the state used by public water systems in an effort to determine the vulnerability and susceptibility to contamination.
SOURCE WATER PROTECTION AREA
Wellhead protection areas and excellent groundwater recharge potential areas.
STORMWATER
The runoff of water from the surface of the land resulting from precipitation or snow or ice melt.
STORMWATER MANAGEMENT
A. 
For water quantity control, a system of vegetative, structural, and other measures that may control the volume and rate of stormwater runoff which may be caused by land-disturbing activities or activities upon the land; and
B. 
For water quality control, a system of vegetative, structural, and other measures that control adverse effects on water quality that may be caused by land-disturbing activities or activities upon the land.
UNDERGROUND STORAGE TANK (UST)
A. 
One or a combination of tanks, including underground pipes, the volume of which is 10% or more below ground, as defined in the Delaware Regulations Governing Underground Storage Tank Systems, dated March 12, 1995.
B. 
The following USTs are not subject to the design, construction, operation, and maintenance requirements of the Delaware UST Regulations: residential heating fuel, agricultural, and residential motor fuel USTs less than 1,100 gallons and any UST less than 110 gallons.
VACANT PROPERTY
Lands or buildings that are not actively used for any purpose as designated in the underlying zoning district/overlay for one year.
WASTEWATER
Water-carried waste from septic tanks, water closets, residences, buildings, industrial establishments, or other places, together with such groundwater infiltration, subsurface water, and mixtures of industrial wastes or other wastes as may be present.
WATER QUALITY
Those characteristics of stormwater runoff from an impervious surface or a land-disturbing activity that relate to the chemical, physical, biological, or radiological integrity of water.
WATER QUANTITY
A. 
Those characteristics of stormwater runoff that relate to the volume of stormwater runoff to downstream-gradient areas resulting from land-disturbing activities; and
B. 
Those characteristics of stormwater that relate to the volume of stormwater that infiltrates the land surface and enters the underlying aquifer.
WELLHEAD
The upper terminal of a well, including adapters, ports, seals, valves, and other attachments.
WELLHEAD PROTECTION AREAS (WHPA)
Surface and subsurface areas surrounding public water supply wells or well fields where the quantity or quality of groundwater moving toward the wells or well fields may be adversely affected by land use activity.
WELLHEAD PROTECTION PLAN
The March 1990 US EPA approved plan for protecting the quality of drinking water derived from public water supply wells in Delaware.
WELLHEAD PROTECTION (WHP) ZONE 1
The surface area extending to a minimum one-hundred-fifty-foot radius around the wellhead.
WELLHEAD PROTECTION (WHP) ZONE 2
The remaining surface area of the delineated wellhead protection area outside Zone 1.
WELLHEAD PROTECTION (WHP) ZONE 3
Where a WHP Zone 2 area overlays an excellent groundwater recharge potential area.
A. 
Source water protection areas are wellhead protection areas and excellent groundwater recharge potential areas. All such areas are as depicted on the Source Water Protection Area Maps located in Town Hall as adopted as part of the update and implementation of the next-applicable Comprehensive Land Use Plan after the effective date of this chapter. These maps are also available in GIS overlays from the Delaware Department of Natural Resources and Environmental Control, Division of Water Resources, Source Water Assessment and Protection Program.
B. 
These areas shall be managed as required by the following sections to protect public drinking water resources from activities and substances that may harm water quality and subtract from overall water quantity.
Activities shall be subject to the land use restrictions contained within this chapter that will protect the quality and quantity of groundwater supplies. All uses not permitted in the underlying zone district are prohibited.
Table 1
Land Use Restrictions and Uses, Source Water Protection Areas
NO - YES — CONDITIONAL
Wellhead Protection Area
Groundwater Recharge Potential Area
Land Use
Zone 1
Zone 2
Zone 3
Excellent
Aboveground storage tanks
No
No
No
No
Automobile body/repair shop
No
No
No
No
Chemical processing/storage facility
No
No
No
No
Dry cleaner
No
No
No
No
Electrical/electronic manufacturing facility
No
No
No
No
Equipment maintenance/fueling areas
No
No
No
No
Fleet/trucking/bus terminal
No
No
No
No
Gas station
No
No
No
No
Hazardous waste: treatment, storage, and disposal facilities
No
No
No
No
# Dry wells/sumps
No
Yes
Yes
Yes
# Injection wells
Yes
Yes
Yes
Yes
Junk/scrap/salvage yard
No
No
No
No
Land divisions resulting in high density (greater than 1 acre)
No
Yes
Yes
Yes
Machine shop
No
No
No
No
Manure storage
No
No
No
No
Metal plating/finishing/fabricating facility
No
No
No
No
Mines/gravel pit
No
No
No
No
On-site wastewater treatment and disposal systems
No
No
No
No
Sanitary and industrial landfills
No
No
No
No
Underground storage tanks
No
No
No
No
Vessel storage
No
No
No
No
Wood preserving/treating facility
No
No
No
No
NOTES:
Conditional:
(#)
Dry wells/sumps, except for single-family residences directing gutter downspouts to a dry well.
(#)
Injection wells other than those used in the remediation of groundwater contamination that inject oxygen-releasing compounds.
A. 
The DNREC Source Water Assessment and Protection Program delineates wellhead protection areas to ensure the integrity of public drinking water. Deep wells drilled into confined aquifers and low-volume wells in unconfined aquifers have, at minimum, a one-hundred-fifty-foot radius wellhead protection area. The wellhead protection area surrounding public supply wells in unconfined aquifers that pump more than 50,000 gallons per day are delineated using a mathematical model. This type of well draws large quantities of water and can have much larger wellhead protection areas. Zone classifications have been created to manage land use within the wellhead protection area. They are defined as:
(1) 
Wellhead Protection (WHP) Zone 1 is the surface area extending in a one-hundred-fifty-foot radius around the wellhead.
(2) 
Wellhead Protection (WHP) Zone 2 is the remaining surface area of the wellhead protection area outside Zone 1. Land use restrictions within Zone 2 are required to ensure adequate protection of public drinking water supply.
(3) 
Wellhead Protection (WHP) Zone 3 exists where a WHP Zone 2 area overlays an excellent groundwater recharge potential area. Land use restrictions within Zone 3 are required to ensure adequate protection of public drinking water supply.
B. 
WHP Zone 1 requirements:
(1) 
Parcels of land within a WHP Zone 1 wellhead protection area will be preserved in a natural condition with the exception of impervious surface limited to building and access associated with the well and distribution and treatment facilities and their maintenance.
(2) 
Aboveground storage tanks for materials used in the treatment facility operation are permitted.
(3) 
Underground storage tanks are prohibited.
(4) 
Stormwater runoff will be diverted away from the wellhead.
(5) 
Stormwater infiltration practices designed to handle runoff are prohibited.
(6) 
The minimum lot area for a proposed public water supply well and related facility drawing from a confined aquifer shall be one acre, and the minimum lot area for a public well drawing form an unconfined aquifer shall be two acres.
(7) 
On-site wastewater and disposal systems shall not be permitted.
C. 
WHP Zone 2 requirements:
(1) 
Impervious cover. Wellhead protection areas within Zone 2 should not exceed 20% impervious cover. New development in this zone may exceed the 20% impervious cover threshold within wellhead protection areas but shall be no more than 50% impervious cover, provided the applicant submits an environmental assessment impact report. (See Environmental assessment impact report, § 181-10.)
(2) 
Stormwater shall be treated by an approved stormwater quality management practice in accordance with current requirements of the Delaware Sediment and Stormwater Regulations dated October 11, 2006, or as later revised.
(3) 
For all new construction, all structures shall be required to discharge roof drains onto nonimpervious cover.
(4) 
Underground storage tanks.
(a) 
Underground storage tanks with a capacity greater than 110 gallons containing petroleum, and residential and agricultural USTs with a capacity greater than 1,100 gallons containing heating fuel or motor fuel, shall not be permitted in a delineated wellhead protection area.
(b) 
Underground storage tanks with a capacity greater than 110 gallons containing a hazardous substance as defined in CERCLA § 101(14) shall not be permitted in a designated wellhead area.
(5) 
Aboveground storage tanks (ASTs) shall not be permitted in a delineated wellhead area.
(6) 
On-site wastewater treatment and disposal systems shall not be permitted.
D. 
WHP Zone 3 requirements:
(1) 
Impervious cover. Wellhead protection areas within Zone 3 shall be preserved in a natural condition. Impervious cover shall not be permitted.
(a) 
Permitted use is:
[1] 
Passive recreation.
A. 
Impervious cover. The excellent groundwater recharge potential area should not exceed 20% impervious cover. New development in this area may exceed the 20% impervious cover threshold within the excellent groundwater recharge potential area but shall be no more than 50% impervious cover, provided the applicant submits an environmental assessment impact report pursuant to § 181-10.
B. 
Stormwater shall be treated by an approved stormwater quality management practice in accordance with current requirements of the Delaware Sediment and Stormwater Regulations dated October 11, 2006, or as later revised.
C. 
For all new construction, all structures shall be required to discharge roof drains onto nonimpervious cover.
D. 
Underground storage tanks.
(1) 
Underground storage tanks with a capacity greater than 110 gallons containing petroleum, and residential and agricultural USTs with a capacity greater than 1,100 gallons containing heating fuel or motor fuel, shall not be permitted in a delineated excellent groundwater recharge area.
(2) 
Underground storage tanks with a capacity greater than 110 gallons containing a hazardous substance as defined in CERCLA § 101(14) shall not be permitted in a delineated excellent groundwater recharge area.
E. 
Aboveground storage tanks (ASTs) shall not be permitted in a delineated wellhead area.
F. 
On-site wastewater treatment and disposal systems shall not be permitted.
A. 
All subdivision and land development plans depicting development or land disturbance submitted for Town review shall be evaluated for the existence of source water protection areas. All such areas are as depicted on the Source Water Protection Area Maps located in Town Hall as adopted as part of the update and implementation of the next-applicable Comprehensive Land Use Plan after the effective date of this chapter. These maps are also available in GIS overlays. Maps/overlays are available from the Delaware Department of Natural Resources and Environmental Control (DNREC), Division of Water Resources, Source Water Assessment and Protection Program (SWAPP). If an SWPA exists within a proposed development site, the boundaries of these areas shall be delineated on the plan by the applicant's State of Delaware professional engineer or professional geologist.
B. 
DNREC SWAPP may, when based on sound science and information, revise and update the overlay maps of wellhead protection areas.
C. 
The Delaware Geological Survey (DGS) may, when based on sound science and information, revise and update the overlay maps of excellent groundwater recharge potential areas.
D. 
When there appears to be a conflict between the mapped boundary and actual site conditions, the applicant may engage the services of a professional geologist to prepare a report intended to determine more accurately the precise boundary of the source water protection area. The report shall include:
(1) 
A detailed topographic layout of the subdivision and/or area, to be developed and prepared by a state-registered professional land surveyor or professional geologist;
(2) 
Evidence derived from a site-specific investigation, that may include aquifer testing, test borings, test pits, observation wells, groundwater elevations, and topography surveys as appropriate for the type of source water protection area, that clearly demonstrate that the area in question does not meet the definition of a source water protection area as defined.
(3) 
Any challenges to the delineations of the excellent groundwater recharge potential areas must follow the methods used in the Delaware Geological Survey publication, Report of Investigations No. 66, Ground-Water Recharge Potential Mapping in Kent and Sussex Counties, Delaware. The challenge must be approved by DGS and DNREC SWAPP.
E. 
Notwithstanding any other section of this chapter, if an owner initiates a precise boundary delineation pursuant to this section, any and all time review limitations shall be stayed pending the submission of the complete report contemplated by this section. Following submission of the report and all supporting documents, the Department shall have 90 days to finally approve or disapprove the exploratory sketch plan submission or such further time as deemed necessary by the Department, but not to exceed an additional 90 days.
A. 
Impervious cover restrictions.
(1) 
Site modifications that require site plan approval must create a 15% reduction in the amount of impervious cover on the site when compared to preredevelopment conditions.
(2) 
If the 15% reduction would require a site to go below the 20% maximum impervious cover provisions of source water protection areas, then the maximum impervious surface cover for the site is 20%.
B. 
Stormwater.
(1) 
Sites that do not meet the 20% impervious cover threshold must employ rooftop infiltration practices. Stormwater shall be treated by an approved stormwater quality management practice in accordance with current requirements of the Delaware Sediment and Storm Water Regulations dated October 11, 2006, or as later revised.
(2) 
If the 15% reduction does not meet the 20% impervious cover threshold, the site must employ rooftop infiltration practices. Stormwater shall be treated by an approved stormwater quality management practice in accordance with current requirements of the Delaware Sediment and Storm Water Regulations dated October 11, 2006, or as later revised.
C. 
Abandoned or vacant property. This section does not apply to vacant or abandoned property. These properties must comply with the source water protection area zoning district regulations.
A. 
Hazardous waste treatment, storage, and disposal facilities, as defined in 7 DE Admin. Code 1302, Delaware Regulations Governing Hazardous Waste, shall not be permitted in source water protection areas.
B. 
Sanitary and industrial landfills, as defined in 7 DE Admin. Code 1301, Delaware Regulations Governing Solid Waste, shall not be permitted in source water protection areas.
A. 
New development in Milton may exceed the 20% impervious cover threshold within excellent groundwater recharge potential areas and WHP Zone 2, but shall be no more than 50% impervious, provided the applicant submits an environmental assessment report including a climatic water budget and systems to augment recharge that assure water quality as well as quantity. The environmental impact assessment must document that post-development recharge will be no less than predevelopment recharge when computed on an annual basis.
B. 
The applicant may offset the loss of recharge due to impervious cover by constructing recharge basins that convey pretreated rooftop runoff for infiltration to groundwater. Refer to Supplement 1, entitled "Ground-Water Recharge Design Methodology," dated May 2005, or later as revised, for the details of how to design recharge facilities in Delaware source water protection areas.
C. 
When an environmental impact assessment report (EIAR) is allowed or required, it shall be prepared by a Delaware registered professional engineer and/or professional geologist and shall contain the following elements of planning, design, construction, and maintenance of groundwater recharge facilities:
(1) 
Site description of proposed development within the water resource protection area.
(2) 
Climatic water balance comparing predevelopment and post-development recharge potential.
(3) 
Subsurface exploration, including borings, test pits, and infiltration tests.
(4) 
Design of groundwater recharge facilities that assures water quality as well as quantity.
(5) 
Construction and maintenance considerations.
(6) 
Recommended groundwater monitoring plan.
(7) 
Water management agreement between the applicant and the Town of Milton providing for monitoring and maintenance of the recharge system.
D. 
The applicant will abide by the groundwater management agreement as written in DNREC Supplement 1 to the Source Water Protection Guidance Manual for the Local Governments of Delaware: Ground-Water Recharge Design Methodology, dated May 2005, or as later revised.
Nonconforming uses may continue in wellhead protection areas and excellent groundwater recharge potential areas in the form in which they existed at the time of the adoption of this chapter, unless they pose a direct hazard to the Town's water supply, as determined by the Milton Public Works Department upon advice from the Delaware Division of Public Health, or are causing some foreign substances (oil, salts, chemicals, or other substances) to be introduced into the Town's water supply, as determined by the Milton Public Works Department upon advice from DNREC's Division of Air and Waste Management and/or Division of Water Resources. In the latter case, the project coordinator and/or his/her designee shall issue a mandatory cease-and-desist to stop the offending activity within the area. Nonconforming existing underground or aboveground storage of oil, petroleum, and petroleum products shall require secondary containment pursuant to the State of Delaware regulations governing underground storage tanks, or for aboveground storage of petroleum products, secondary containment facilities capable of capturing the material stored on the site, for existing facilities that are proposed either to be upgraded or replaced.
A. 
The replacement of any existing public water supply well that was not required to meet this wellhead protection requirement at the date of its original installation and that has failed shall be exempt from meeting this wellhead protection requirement.
B. 
All public water supply wells within a housing development, subdivision, or strip development recorded on or after the implementation of the Delaware Regulations Governing the Construction and Use of Wells, dated April 6, 1997, or as later revised, shall be located at least 150 feet within the subdivision's or development's outermost property lines.
The following are exempt from the requirements of this chapter:
A. 
Wells used for agricultural purposes;
B. 
Replacement wells;
C. 
Minor subdivisions;
D. 
Recorded subdivisions;
E. 
Revisions to recorded subdivision plans that do not result in the creation of additional lots;
F. 
Minor changes or alterations to approve site plans in accordance with Chapter 220;
G. 
Improvements to existing residential lots, including additions to existing single-family dwellings, the placement of sheds and fences; and
H. 
Subdivision and land development projects that have received preliminary plan approval by the Planning and Zoning Commission, conditional use site plans that have received approval by the Commission, conditional use site plans for public water supply in an existing recorded subdivision or concept plan approval in the case of residential planned communities and cluster subdivisions shall not be subject to the provisions of this chapter for as long as their approval remains valid.