Services: Residential Site Development Plans

Residential Site Development PlanAre you looking to build your dream house or construct that addition you’ve always been talking about? Whether you currently own a piece of property or you are looking to buy, there are a number of factors you need to consider before breaking ground. Prior to developing a layout for the development of a residential lot, it is necessary to consider a wide variety of factors that will ultimately dictate the way the site can be developed. The manner in which a residential lot can be developed is largely influenced by the terrain and natural features of the site. In addition, many local, state, and federal land use regulations that pertain to zoning, health, and inland wetlands can all affect the way a residential lot can be developed. The planning, civil engineering, land surveying, and environmental services staff of Arthur H. Howland & Associates, P.C. can help you identify the various factors associated with developing a residential property and then help you move forward with a site layout that compliments your dream house while still complying with local, state, and federal land use regulations.

Determination of Environmentally Sensitive Areas

One of the first steps in assessing how a residential property can be developed is to determine the existence of any environmentally sensitive areas on or near the property. The location of wetlands, watercourses, floodplain, vernal pools, steep slopes, and other environmentally sensitive areas on or in relation to a property influences how a property can be developed. During the early stages of the project, it is important to identify these environmentally sensitive features of a property. To determine whether or not wetlands and watercourses lie on a property, it is recommended to have a soil scientist walk the site to make a determination. If wetland soils do exist on a site, the soil scientist must then return to the site to field delineate (flag) any areas of wetlands and watercourses. It is also recommended to have the site engineer visit the site during this preliminary stage of the project to identify any other environmentally sensitive areas or areas of special concern that may exist on the property. Examples of these other environmentally sensitive areas include the existence of exposed or shallow bedrock, steep slopes, drainage concerns, floodplain, or any other concerns that may affect the development of the property.

Existing Conditions & Property Survey

Once the environmentally sensitive areas of a property are identified, it is then necessary to have a property survey performed that establishes the limits of the property and accurately depicts the location of any physical structures and environmentally sensitive areas on the site. A topographic survey will also need to be performed to provide elevation information so that the site terrain can be depicted on the property for use during design. All information collected during the survey stage will serve as base mapping for the layout and design of the house, driveways, septic system, well, utilities, and any other aspect of the project.

Inland Wetland & Watercourse Regulation

To protect wetlands and watercourses, most municipalities in the State of Connecticut have established regulated areas within certain distances of a wetland or watercourse where all development is regulated by the local Inland Wetlands & Watercourses Commission. In order for development to be allowed within a regulated area, the applicant must prove to the commission that a subject wetland or watercourse will not be detrimentally impacted by the development proposed. Sometimes projects that contain no wetlands or that are completely outside of a wetland regulated area may also be regulated by the local Inland Wetlands & Watercourses Commission due to the project’s location upgradient of a wetland or watercourse or the project’s drainage connectivity to the watercourse or wetland.

Floodplain Regulation

Development within a watercourse floodplain is typically not allowed. In the rare cases where development or filling of a floodplain is allowed, compensation must be made by the developer, as part of the site development plan process, to provide additional floodplain storage to make up for any floodplain storage volume lost by development. A floodplain analysis of a watercourse may also be required to determine the impact that filling within a floodplain may have on flood elevations within a watercourse’s banks. Any proposed construction or disturbance within a floodplain must ultimately be approved by the United States Army Corps of Engineers. Due to the large amount of work and permitting required for projects within a floodplain, development within a floodplain is typically considered cost prohibitive.

Zoning Compliance

Another initial step in the Residential Site Development Plan process is to determine the zone of the subject residential property. Since most municipalities have multiple residential zones, that can vary significantly with regard to setbacks and what is allowed, it is very important to know which zone the the project is located in. Zoning regulations typically make reference to building setbacks, building heights, building coverage, site impervious coverage, driveway widths, driveway grading, landscaping requirements, driveway sight distance and other requirements that are specified for all new construction within that zone.

Preliminary Residential Site Layout

Once a site’s environmentally sensitive areas are located and all pertinent regulations are identified, it is then possible to develop a layout for the residential property. During this phase, it is essential to work with the client and the client’s architect to develop a clear understanding of their needs and goals for the site. Once there is a clear understanding of the client’s vision for the site, it is then possible for the engineering staff of Arthur H. Howland & Associates, P.C. to develop a layout that meets the client’s goals while taking account for any local, state, and federal regulations that may apply to the project.

House Location Considerations

When determining the ideal location for a house or addition, it is important for the client to consider the size, desired location, and orientation for the house or addition. When siting the house or addition, it is very important to take into account the location of any nearby environmentally sensitive areas such as wetlands, watercourses, steep slopes, shallow bedrock, and any other areas that may affect or restrict development. In areas with steep slopes, the client may consider a house with a low level walkout to work better with the existing terrain of the land. Another consideration to keep in mind when siting the house is to determine how the driveway will service the house. Sometimes a driveway that enters a garage at the front of the house may work better than a side entry garage or vice versa.

Driveway Considerations

During the initial stages of the site layout, it is also extremely important to make sure that a driveway can be constructed from the roadway or common driveway servicing the property to the desired location of the house. Most municipalities have regulations governing the maximum slope in which a driveway can be constructed. If the desired house location is elevated on a steep slope, there is a good possibility that the driveway servicing this property may not be able to be allowed by a municipality’s zoning regulations without the use of a winding driveway layout. Another consideration associated with the placement of a residential driveway includes making sure that proper sight distance is provided where the driveway meets the roadway it intersects. To provide for safety, most municipalities and the State of Connecticut have established sight distance criteria that should be provided for a driveway that intersects a local or state road. Depending on intersecting horizontal and vertical roadway geometry, a driveway needs to be placed along a roadway to meet the minimum standards set forth by the governing agency. In instances where there is no location where sight distance can be provided, work within the right of way of a local or town road may be required to provide for safer conditions.

Water & Wastewater Considerations

Another important requirement in the development of a residential lot is to provide for water and wastewater service to the proposed house. In most urban environments, water is typically provided through the connection of the proposed house to municipal water and sanitary sewer mains. In more rural areas, water is typically supplied to a house through the use of a private well and wastewater needs are provided using a subsurface sewage disposal system (septic system). In urban areas, connection to the sewer and water services is typically coordinated with the local water company and water pollution control authority. In rural areas, the construction of wells and septic systems are typically governed by the local health agency and the State of Connecticut Department of Public Health. While connection to public water and sewer mains does not typically require a large amount of land, the construction of private septic systems and wells can be land intensive and require more extensive separation distances from various entities on a residential property.

When developing a septic system design, it is necessary to do soil testing in the desired location of the septic system. During the investigation, the site engineer or soil scientist witnesses the excavation of deep test pits in the area of the potential septic system. While witnessing the test pits, the site engineer or soil scientist examines the soil strata to determine the existence of restrictive layers such as high groundwater, shallow bedrock, or mottling. If the restrictive layers are shallow and do not meet the requirements of the local and state health code, then the area is not suitable for a septic system and another area must be investigated. If no restrictive layers are found or if the restrictive layers are deep enough to meet the local and state health codes, then an additional test called a percolation test is run in the area of the deep testing. The percolation test measures how fast water can percolate into the ground. Once both tests have conducted and an area is determined suitable for a septic system, the septic system can then be sized based on the number of bedrooms the house will have.

Drainage Considerations

During the preliminary stages of a residential project, it is also wise to consider the existing drainage issues and patterns of the site. In order to avoid stormwater impacts to neighboring downhill properties, wetlands, or watercourses, it is important to come up with a means for attenuating the additional runoff that is typically associated with building driveways and houses. When a piece of land is developed, the amount of hardscape or impervious surface is typically increased resulting in an increase in the amount of water that will run off from a site to downhill properties, wetlands, and watercourses. To attenuate this increase, it is necessary to develop a stormwater management system that provides temporary storage and a controlled release of stormwater from the site so as not to increase the peak runoff rates from the site. Stormwater management systems for residential properties may include measures such as underground infiltration units, underground storage chambers, drainage trenches, and drainage channels. While these stormwater management systems are sometimes an afterthought, it does make sense to consider the placement of a stormwater management system during the preliminary phase of the project as it will take up some space and will require adequate separation from other aspects of the site such as the septic system and the well.

Residential Site Plan Design

During the design phase, the more detailed aspects of the project are addressed. Site grading is provided through the use of spot grades and contour lines. A cuts and fill analysis will typically be included during the development of site grading to minimize the need for removing excess soil material from a site or require additional fill material to be trucked onto a site. Detailed information regarding the proposed drainage systemsewer or septic system, water supply system , and other siteutilities is also provided. A detailed stormwater management system which attenuates any potential impact to peak runoff flow rates and stormwater quality is analyzed and designed. Sedimentation and Erosion Control measures and construction sequences are designed and developed to minimize any effect the development may have on wetlands and watercourses during construction. During the design phase, it is also necessary to ensure that the driveway will have appropriate intersection and stopping sight distance. Details regarding construction materials and methods are also specified at this time. In addition, we also work with other industry professionals such as landscape architects and wetland specialists who aid in developing compliant landscaping plans and wetland mitigation plans.

Once the final design plans are developed, they are then submitted with the appropriate application and presented to the local land use commissions and agencies having jurisdiction over the project for approvals. If the project is proposed in the vicinity of an existing wetland or watercourse, an Inland Wetland & Watercourse Permit would be required. Following inland wetland approval or if no inland wetland approval is required, the project is then submitted to obtain local planning and/or zoning approval. Following all local approvals, the project would then need to be submitted for any other state and federal permits that would apply to the project. During the local, state, and federal permitting process, the reviewing agencies may offer comments or express concerns over issues relating to the site development plan. Depending on the comments, the design engineer may need to revise the plans to address any concerns that are raised. This iterative process, which involves some back and forth, typically results in a project approval and a development where all parties concerned are comfortable.

Proven Experience and Results

The design and permitting process associated with residential site plans can be an involved yet extremely rewarding process. The land surveyingplanningcivil engineering, and environmental services staff of Arthur H. Howland & Associates, P.C. has successfully designed and presented numerous residential site development projects that have been approved by various land use commissions and agencies throughout the State of Connecticut. Our established relationships with various local, state, and federal agencies combined with our ability to collaborate with architects and other industry professionals to produce and present attractive, value engineered designs sets us apart from our competition. If you are interested in constructing your dream house or dream addition, contact us at (860) 354-9346 so that we discuss your project and show you examples of our most recent residential site development plans.

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