Ohio Coastal Design Manual
|Chapter 2 |
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Promote better projects along the coast that balance the use of Lake Erie as a shared natural resource along with the property owners’ need for lakefront erosion protection and the benefit of access to the lake.
This chapter describes the unique conditions of performing topographic and boundary surveys along Ohio’s Lake Erie coast for projects that require authorizations from the Ohio Department of Natural Resources (ODNR).
The purpose of this chapter is to assist the professional surveyor in establishing accurate site control, the collection of field data, the research of public records and the preparation of application submittals for projects proposing to occupy portions of the Public Trust Territory of Lake Erie, including the waters of Maumee Bay and Sandusky Bay.
Chapter 2. Site Surveying Requirements
Horizontal and vertical datums
A horizontal control network establishes horizontal positions, or plane coordinate values, on each station or point for a variety of surveys. Topographic surveys determine the configuration of the earth’s surface and location of natural and artificial features, while cadastral surveys retrace property lines. A traverse is a method by which lengths and directions of lines between points on the earth are observed from field measurements to determine positions of those stations. The design of a horizontal control network for preliminary topographic and/or cadastral surveys should include a traverse that surrounds the entire site. A closed traverse is a convenient, rapid method for establishing horizontal control and is particularly useful in densely built up areas along the Lake Erie coast and in heavily forested regions where lengths of sight are short.
Although there is no requirement for field surveys to be based on a specific horizontal datum and coordinate system, it is beneficial to use the Ohio State Plan Coordinate System North Zone (SPC3401) which is based on North American Datum of 1983 (NSRS 2007).
Alternatively, control surveys using the Global Positioning System (GPS) may prove to be the best solution, especially for open areas where there are no physical obstructions. Consideration must be given to errors in positional accuracy created by multipath issues when collecting data near the waters of Lake Erie. Multipath errors occur when buildings or other obstacles block the direct path of the satellite signal to the GPS receiver and there is a time delay of the reflected signal to the receiver. Dilution of Precision (DOP) values are an indicator of the quality of the satellite arrangement. Increased values in the DOP that introduce error to the control or topographic survey can be observed when collecting data near the vertical bluff face and tree canopy.
Datums define the shape and size of the earth, or a portion of it, based upon an origin and direction of the coordinate systems. Datums available to the surveyor performing horizontal control surveys include several local datums created for small geographic areas and geodetic datums that define the spherical model of the earth such as the North American Datums of 1927 and 1983, and the World Geodetic System (WGS).
Coordinate systems that define points in space by distance and direction based upon either a local or a geodetic datum have been established by municipalities in each of the eight coastal counties. Referencing coordinates to the wrong datum can result in positional errors when performing or positioning field surveys. Although there is no requirement for field surveys to be based upon a specific horizontal datum and coordinate system, it is beneficial to utilize the Ohio State Plane Coordinate System North Zone (SPC3401) which is based upon North American Datum of 1983 (NSRS 2007). The benefits of using a common datum include digital data sharing by regulatory agencies, consultants and county administrators; accessibility to published monumentation by the National Geodetic Survey (NGS); and maintaining coordinate integrity for multiple project sites.
Land parcel data provides geographically referenced information associated with the real property and generally forms a structure of polygons within a defined area. The OCM uses parcel data generated and maintained by each county auditor’s office as a framework for locating specific sites and alignments of rights of way. Survey products produced, reviewed and distributed by OCM are referenced to parcel data obtained from the corresponding county auditor’s office. OCM recognizes that these boundaries and alignments are not survey accurate. Although this dataset is based upon SPC3401, OCM does not routinely field-verify the locations of intersecting centerlines for rights of way or parcel corners. Coastal permit and lease application submittals that identify coordinate values for subdivision corners or intersecting centerlines based upon SPC3401 or WGS 1984 are incorporated into OCM’s Geographic Information System (GIS).
A vertical control network establishes vertical positions, or elevations, on each station or point for surveys that relate a vertical distance from a datum. A closed level circuit is the preferred procedure for determining the elevations as this method provides the surveyor the ability to adjust observations based upon lengths of the sights between each station. Although this method may not be as convenient as control surveys using the GPS, the results may be more accurate.
Datums available to the surveyor performing vertical control surveys include several local datums, and resultant benchmark systems established by municipalities in each of the eight coastal counties and geodetic datums such as National Geodetic Vertical Datum of 1929 (NGVD 29), North American Vertical Datum of 1988 (NAVD 88) and International Great Lakes Datum of 1985 (IGLD 1985).
For project sites that are within the regulatory jurisdiction of the United States Army Corps of Engineers (USACE), Ohio Environmental Protection Agency (OEPA) and ODNR, application submittals must provide a reference to the most current International Great Lakes Datum (IGLD).
The vertical distance from the point on the earth’s surface to the geoid model, NAVD 88 for example, is a true orthometric height. IGLD 1985 is reported as a dynamic height that is calculated from the orthometric height and a value of the geopotential related to gravity. Therefore, there is not a single conversion factor between these datums. A calculated conversion from a relative, reference or local vertical datum to IGLD 85 must be provided if the field survey was not based upon IGLD 1985. NGS’ website: http://vdatum.noaa.gov provides tools to convert between various vertical datums.
OCM has included survey monumentation as a thematic layer within the Lake Erie Ohio Coastal Atlas Project’s Interactive Map Viewer. Located on OCM’s website: www.ohiodnr.com/tabid/23320/default.aspx this tool allows the consultant to identify all First or Second Order monuments, (those that have a high level of accuracy and precision for the vertical component) within a certain radius of a specific location within Ohio’s eight coastal counties. A link to the current NGS datasheet is included. (top)
Existing site conditions and structures
Adjusted horizontal and vertical control networks allow the surveyor to locate the natural and human-made features on the site. These features may provide reference points to the location of the water’s edge and/or top of bluff as depicted on historic plats and aerial photography. Site features may also be used to identify impacts upon the rights of the littoral property owner such as adverse possession claims and prescriptive easements that can influence design choices or construction methods.
The location of all fills and structures along the shore should be referenced to the upland parcel boundaries so that inconsistencies between boundary lines described in the title and the claimed possession by the occupation of human-made structures can be identified. The surveyor should coordinate with the design engineer for the project to assure that all features within the project area are defined in location, elevation and dimension. This includes adjacent structures along, near and/or offshore that may affect the upland owner’s ability to exercise their littoral rights, potentially affect littoral transport or influence design choices.
Sufficient topographic and bathymetric data should be collected to build a digital elevation model (DEM) of the bare-earth, to generate contours and to accurately represent the elevation surface. Digital terrain models (DTM) may include the surface of buildings, water and tree canopy.
Joining datasets obtained from varying sources to generate any DEM requires an evaluation of the data collection techniques. These include the coordinate system utilized, its origin and accuracy and other characteristics included in the metadata. In order to determine the model grid spacing between field located points, the surveyor should evaluate the collection methods used, the datum and the desired type of surface (DEM/ DTM) needed to depict the data.
Grid spacing in bathymetric data collection is dependent upon the degree of elevation change, the geographic limits of the project site and the software application used in processing the dataset. Additional guidelines for bathymetric profiles are included in Chapter 3.
A grid arrangement comprised of asymmetrical points, referred to as a Triangulated Irregular Network (TIN), has an associated elevation at each vertex and can enable a more detailed depiction of elevation changes upon the surface model at strategic locations along significant features (i.e. water’s edge), and less detailed depiction where there is a consistent grade.
A site plan prepared by the surveyor that depicts the existing conditions must be signed, sealed and dated by the Ohio registered professional surveyor. By affixing their seal to any document, the registrant certifies to the accuracy and completeness of the information contained in the sealed document, and by such action, assumes full responsibility thereof. (Site plans not expressly prepared for the depiction of legal boundaries may also be prepared, signed and sealed by an Ohio registered engineer referencing the plans and data prepared by the surveyor.) Site plans are included in the five design examples in Chapter 4. (top)
Determination of the parcel boundaries for the site
Boundary surveys along Lake Erie’s shoreline require that the surveyor collect and evaluate all available evidence or data required to make a determination on the location of the ambulatory boundary. This evidence should include, but should not be limited to:
Historic aerial photography.
Previous surveys of record.
Previous conveyance instruments to discover the intent of the grantor.
Water gauge data.
Nautical chart data.
Geomorphic features that define the earth’s shape or surface collected by a field survey.
Existing site conditions.
Visual inspection of the site for hydrologic, vegetative and geomorphic indicators provides information that can be evaluated and incorporated into the natural shoreline determination. Natural processes such as accretion, avulsion, reliction and erosion must be considered in any determination of the ambulatory boundary defined by the body of water. All evidence should be weighed accordingly.
When fill material has been artificially placed on the site, further examination of the evidence must be made to determine the location of the natural shoreline prior to that activity. Examples of such evidence include:
Information obtained through soil borings.
Search of regulatory agency records.
Drawings that depict pre-construction site conditions.
Inspection of historic aerial photography.
Parol evidence taken at the site.
Historic aerial imagery can be examined to determine the location of the water’s edge prior to the placement of fill and to establish an approximate period for that activity. Sources for historical aerial imagery datasets include ODNR, the Ohio Department of Transportation Office of Aerial Engineering, county engineer’s and auditor’s offices, county soil and water conservation districts, utility companies and historical societies. When aerial photography is used to compare and identify changes to the shoreline, either by naturally occurring processes or disruption due to manmade structures and fills, an examination of the impacts of coastal processes (i.e. erosion, accretion) on the adjacent shoreline must be performed.
The surveyor should seek advice from legal counsel on rulings from the court and the applicability to any specific site. Consideration of how Ohio courts have decided cases involving erosion, placement of artificial fill, and extinguishing of title (i.e. Beach Cliff Trustees v. Ferchill) must be factored into any determination.
Citation of all collected evidence and resulting conclusions should be documented in a surveyor’s report that must be signed, sealed and dated by the Ohio registered professional surveyor. By affixing their seal to any document, the registrant certifies to the accuracy and completeness of the information contained in the sealed document, and by such action, assumes full responsibility thereof. (top)
Depicting the littoral partitions
between adjoiners for the site
Lakefront property owners have certain rights that are included in the “bundle of rights” held by the titleholder. Boundary lines of the upland parcel are projected into the waters from the natural shoreline and form a division line, or partition, between contacted owners and their respective littoral rights. It is the duty of the surveyor to make a determination of where one owner’s boundaries begin and the neighbors’ boundaries end including the limits of any littoral rights within the waters of Lake Erie.
There are multiple established methods for determining the littoral rights partition lines between parcels that are directly contacted (or “adjoined”). It is critical to examine the appropriate reach of shore when apportioning between several nearby or “adjacent” parcels that have a close proximity to the subject parcel. In some cases it may require the surveyor to extend the field location survey a significant distance from the project site.
Several elements should be considered in partitioning these rights within the waters of Lake Erie. Among these factors are the alignment of the reach of shoreline that is to be apportioned, the ambulatory nature of the water’s edge and the location of the natural shoreline prior to any alteration caused by humans. The artificial placement of fill material within the waters of Lake Erie or along its shore, or the excavation of private lands to create marina basins does not change the location of the natural shoreline.
A general rule of procedure is to project partition lines perpendicular to the natural shoreline at the point where the upland parcel boundary intersects the natural shoreline. In cases where the natural shoreline alignment is concave, as in an embayment, or convex, as on a peninsula, a center point is calculated and these projection lines are drawn radial to that point.
There are instances in which the sidelines of the upland parcel boundary should be controlling and perpendicular and where radial projections should not be made. Examples of this circumstance include where the upland sideline has the same boundary without gap or overlap, (or is “coterminous”), with the fractional section or township due to the border with the water boundary or the adjoining survey district. Range lines or original Ohio land subdivision lines throughout Erie County and the Danbury Township portion of Ottawa County (also known as the Firelands) can create the same condition.
Due to the varying conditions along the 312 miles of Lake Erie shoreline within Ohio, it would not be practical to apply one single method. However, as a rule, the alignment of upland sidelines should not control the alignment of partition lines into the waters of Lake Erie. In some instances, due to the irregularly shaped configuration of the shoreline, multiple methods may produce the best result based upon equitable distribution.
Methodologies that may be appropriate along Ohio’s Lake Erie shore are contained in several reference manuals including the 2009 “Bureau of Land Management Manual of Instructions for the Survey of the Public Lands of the Unites States,” and “Brown’s Boundary Control and Legal Principles.” A review of Ohio case law and tests of equity for the adjoiners should be examined for each situation. (top)
Survey products for projects
under the regulatory authority of ODNR
OCM administers the Submerged Lands Lease Program for the state of Ohio based upon Ohio Revised Code Chapter 1506.11 and Ohio Administrative Code Chapter 1501-6. Submerged lands leases are different from conveyances of fee simple interest in that the state of Ohio cannot convey clear title to Public Trust Lands. However, the state can convey a limited leasehold interest to the upland parcel owner for a portion of the territory based upon the proposed development within the waters of Lake Erie.
To enable ODNR to administer the Submerged Lands Lease Program effectively, an accurate depiction of the proposed lease boundary is needed. For most projects, the lease boundary must have a direct connection to the adjacent upland parcel and the Ohio Registered Professional Surveyor identifies this relationship by submitting a plat of survey that depicts the proposed lease boundary and the upland title lines. This requirement is intended to ensure that lease boundaries close, that the area to be leased is accurately identified and overlaps are eliminated.
In 2006, the state of Ohio Board of Registration for Professional Engineers and Surveyors provided an opinion to ODNR on the applicability of Ohio Revised Code Chapter 4733 and the rules adopted thereunder to the state of Ohio Submerged Lands Lease Program. The board stated that registered professional surveyors are the only people qualified to prepare descriptions for the establishment and retracement of lease boundaries and therefore the surveyor shall conform to the Minimum Standards for Boundary Surveys of Ohio Administrative Code Section 4733-37.
ODNR evaluates the impacts of the project on the littoral rights of landowners along Lake Erie based upon the plat drawings and metes and bounds descriptions prepared by the Ohio registered professional surveyor. The plat drawing shows partition lines that indicate a separation of rights within the waters of Lake Erie in areas between upland parcel owners. The determination of the location of the partition lines must consider the equitable distribution of the shoreline and the rights of adjacent upland property owners.
The footprint of the structure, and therefore the limits of the submerged lands lease are not required to extend to the littoral rights partition lines of the upland parcel. In instances where the proposed lease boundary extends beyond the partition line, the affected adjoiner must grant their consent in writing either by providing an affidavit to that fact or by supplying an agreement between the private parties.
Depending upon the project, an application for a Lake Erie Submerged Lands Lease may require a metes and bounds description of the submerged land to be occupied with the area reported in square feet to enable an annual lease rental amount to be calculated. In certain cases, an alternate description that is referenced to the applicant’s upland property description may be considered by the director of ODNR. Alternative descriptions may include: a plat of survey that depicts the boundaries of the upland relative to the occupation of submerged lands with the area reported in square feet; bounding; or coordinate descriptions for specific off-shore projects.
There are two exceptions to the requirement for a metes and bounds description: private floating piers and linear utility installations.
For applications for a floating pier, a basic site plan that depicts the general location of the proposed structure is sufficient, without a field survey.
Utility descriptions and/or plats should depict the centerline of the proposed occupation and identify a distance offset to allow for alignment adjustments during construction due to submerged features and for maintenance of the conduit.
ODNR encourages each leaseholder to file the executed submerged lands lease with the county recorder’s office in which the site is located. Currently this is not a requirement, but ODNR is developing procedures to file all submerged lands instruments to enable surveyors, realtors, title agents and others to identify interests within the waters of Lake Erie.
In order to insure the submission of proper and accurate legal descriptions of the submerged lands to be occupied, ODNR provides the following guidelines. (top)
Metes and bounds descriptions
In its best form, a written description identifies a unique area without conflict with any other portions of land. It must be retraceable for the surveyor and accurately depict the intent of the grantor. It must include monumented and identifiable commencing points, distinct calls to adjoiners and mathematically close within allowable tolerance defined by Ohio Administrative Code Section 4733-37.
Metes and bounds descriptions are used to identify the entire area of proposed, as well as existing occupation of the territory of Lake Erie. Descriptions are attached as an exhibit to the executed submerged lands lease. Current Ohio Administrative Code rules for submerged lands leases identify specific rental categories based upon the primary use of the submerged lands of Lake Erie. In instances where there are multiple uses within the same site, separate metes and bounds descriptions referenced to a common point of commencement must be provided.
To allow the lease instrument to be recorded, each description must include the area reported to the nearest square foot and acreage to the appropriate decimal place according to the current conveyance standard established by the county auditor’s and engineer’s office where the project is located. The surveyor should review these conveyance standards, which can be accessed through the Ohio Department of Transportation web site: (top)
Metes and bounds descriptions are included in the design examples in Chapter 4.
Plat of survey for the submerged lands lease parcel
A graphic representation of the proposed submerged lands lease boundary is required to accompany any metes and bounds description. The text and graphics shown on the plat of survey assist the upland owner, real estate professional, engineer and surveyor in understanding the intent of the state of Ohio to convey a limited leasehold interest for the area in the description. Other information on the plat must include:
Any interest in submerged lands (i.e. lease or permit) on the site, including adjoiners;
Identification of existing and/or proposed overlap or gap;
The methodology employed in determining the partition of littoral boundaries for each adjoining shoreline parcel;
The manner by which the coterminous boundary between the public’s interest in the waters of Lake Erie and the upland parcel was established; and
The direct relationship between the upland parcel and the proposed lease area.
The plat depicting the entire area of proposed and existing occupation of the territory of Lake Erie is attached as an exhibit to the executed submerged lands lease and must conform to the respective county conveyance standard. Survey plats are included for the design examples in Chapter 4. (top)
Surveyor’s role during project construction
Construction layout surveying along the shore and in the waters of Lake Erie can be challenging as traditional layout techniques and error tolerances must be adjusted to the site conditions. The accuracy of measurements and the type of temporary survey markers vary with the degree of precision required and type of construction.
During construction, site conditions may require that the design be modified to meet unexpected conditions or changes to the project scope. Any modification to the design of the project requires the approval of the Ohio registered professional engineer responsible for the design. Modifying the design in the field without such approval may relieve the engineer of liability for the design. (top)
Post construction surveys
As-built surveys create a record of the site conditions after all construction activities have been completed. This is sometimes necessary to identify the actual location of features due to either planned or un-planned deviations from the design during the construction.
As-built surveys can also document the location and alignment of the shoreline prior to the impacts of littoral processes such as erosion and accretion on the project. The effects of these processes may influence the upland parcel boundary and the rights of adjoiners to the accreted material. Ideally, the same person that performed the control, boundary, preliminary topographic and construction layout surveys would complete the as-built phase of the project. This is not a requirement for an accurate as-built, however it is required that the surveyor locate and use the horizontal and vertical control stations that were the basis for the other phases of the project. This recovery enables the surveyor to locate field changes on the same coordinate system that the design was based upon. It allows the engineer and property owner to easily identify any modifications to the design and impacts on the surrounding features. (top)