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Need for a Multipurpose Cadastre (1980)

Chapter: Technical Requirements

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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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Suggested Citation:"Technical Requirements." National Research Council. 1980. Need for a Multipurpose Cadastre. Washington, DC: The National Academies Press. doi: 10.17226/10989.
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3 Technical Requirements The creation of compatible multipurpose cadastres requires the input from many different sources. Transactions and records of municipal, county, state, and federal agencies feed into the system. The major federal participants will include the Bureau of Land Management, the Land Acquisition Section of the Department of Justice, the U.S. Geological Survey, the National Geodetic Survey, the Bureau of the Census, the U.S. Department of Agriculture, the Department of Housing and Urban Development, the U.S. Forest Service, and the U.S. Army Corps of Engineers. The effectiveness of the multipurpose ca- dastre network will depend primarily on the degree of participation by munic- ipal, county, and state governments and in their conception of the benefits to be gained at these levels of government from the free flow of data and in- formation. A major share of the benefits will accrue to private conveyances. Since most contributors will also be users, it behooves all to maintain rigid quality-control standards. The network of multipurpose cadastres must be properly coordinated, organized, and maintained. A well-thought-out linkage mechanism will make it effective nationwide. Based on the elements of Sec- tion 1.4 and Figure 1.1, the details of such a cadastre and how it can function serving needs and different purposes are illustrated in Figures 3.1 (a) and 3.1(b). Representative acquisition modes (geodesy, field surveys, and photo- grammetry) are presented that lead to the elements of the multipurpose cadastre reference frame as described in Section 3.1. Similar information is presented (acquisition modes and elements) for the multipurpose cadastre base map and cadastral overlay described in Sections 3.2 and 3.3, respective- 44

Technical Requirements 45 ly. With these three components of the multipurpose cadastre in place (com- pletely or partially), the elements of the linkage mechanisms, discussed in Section 3.4, are given, which will connect the land information and data files to the three basic components of a multipurpose cadastre. A network of com- patible multipurpose cadastres will permit the free flow of information among all levels of government, private individuals, and institutions. The sections following give more detailed descriptions of the technical re- quirements for the reference frame, base map, and cadastral overlay aspects of a multipurpose cadastre, introduce mechanisms that may be considered in de- velopment of multipurpose data systems; discuss some needed improvement in surveying practices that will establish the cadastre on a firm basis; and con- sider the roles of public and private utilities. 3.1 GEODETIC REFERENCE NETWORK A survey control base is needed to create an integrated land-records and -in- formation system. Monumented points whose coordinates have been deter- mined with respect to the national geodetic control system constitute such a system. This system permits spatial reference of all land data to identifiable positions on the earth's surface. It can be used to form a common index for the land-records and -resource information when that information contains a coordinate reference to the earth's surface. The most stringent spatial requirements to be imposed on the system will determine the design of the survey control base. For example, property owners, developers, or contractors might want to establish or determine the location of property boundaries, rights of way, or utility lines within a toler- ance of a few centimeters. A highly accurate base is a prerequisite for such precise position determination. Also, as land values and competition for the use of land increase, the acceptable measurement error will likely become smaller, Therefore, not only present but future requirements must be de- signed into the system. Maintenance of the survey base is a requirement, since portions will be lost each year, if adequate maintenance is not provided. The establishment and maintenance of the survey base, whether by federal, state, or local agencies, consistent with federal standards (Federal Geodetic Coordinating Committee, 1978) would increase its reliability and provide the consistency desired for a network of compatible multipurpose cadastres. Recent improvements in sur- veying technology can provide the means of establishing and maintaining the survey base economically.

1 LINKAGE MECHANISM Parcel Identifier Parcel Index Geographic Coordinates Street Address Standard Terms • Standard Procedures Standard Data Storage Units Standard Data Retrieval Units (Section 3.4) 8 Metes & Bounds Surveys Official Cadastral Surveys (BLMj Other Legal Surveys Recorded Plats • Subdivisions -Amalgamations • Easements • Registration Utility Records CADASTRAL OVERLAY Cadastral Parcels Boundaries Easements Harbor Lines Riparian Rights Wetlands Utility R/W Tunnels Mines Wen Sites (Oil, Gas) (Section 3.3) BASE MAP Geodetic Control Township Corners Section Corners Public Lands Roads Railroads Waterways Wetlands Airports (Section 3.2) Photogrammetry Reid Surveys BLM Records Geodesy Field Surveys L , Photogrammetry j (a) REFERENCE FRAMEWORK Coordinates Locations of Reference Points Geodetic Reference Network Bench Marks • Tidal Benchmarks (Section 3.1) 46

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48 NEED FOR A MULTIPURPOSE CADASTRE 3.1.1 Local Densification of the National Geodetic Net All coordinated reference points should be tied to the national geodetic sys- tem. This is the thrust of standards proposed in the preliminary report of the North American Institute for the Modernization of Land Data Systems' Ad Hoc Committee formed by representatives of the American Bar Association and the American Congress on Surveying and Mapping (Chatterton and McLaughlin, 1975). In Section 5.3 of that report the following is recom- mended: The committee has concluded that "all descriptions of land parcels, easements, and other interest in land required for conveyancing, taxation, and any other purposes should be ultimately tied to the state/provincial plane coordinate system." Only in this way can the consumer be afforded acceptable protection .... The practical implementation of these recommendations can be achieved only if a sufficiently dense network of permanent survey monuments, consti- tuting a survey base, is established throughout each appropriate jurisdiction unit. Where an appropriate survey base is in place, it becomes equitable and economically feasible to require by law that property surveys be tied to the system. At present, in only about 15 percent or so of the 500 counties in the United States, designated by the Department of Commerce as "primary" counties in terms of population density, are there in place segments of the national geodetic network of sufficient density to serve as a logical starting point for densification to a level that would support a cadastre. It is clear that formidable obstacles need to be overcome for the realiza- tion of a sufficiently dense geodetic network that can serve the needs of the cadastre. Even where the primary geodetic system is already in place, its den- sification by conventional ground traversing is a costly and time-consuming undertaking. Nevertheless, conventional ground surveying can generate the geodetic data base necessary for the establishment of a cadastre, provided that the surveyor maintains adequate standards. Several examples exist of suc- cessful projects executed conventionally in the United States and Canada. These include projects in the Maritime Provinces of Canada (Greulich, 1979); Racine County, Wisconsin (Bauer, 1976); and Monroe County, New York (Moore, 1970). Because of cost constraints, widespread implementation of the cadastre may well depend on the development and application of new technology. Within the past five years, three emerging technologies have achieved recog- nition as practical and cost-effective alternatives to conventional ground sur- veying in significant applications; these are Doppler satellite surveying, high- precision photogrammetric surveying, and inertial surveying (Mueller and Ramsayer, 1979). The Doppler system is reviewed and adopted (within de- fined limits) as an acceptable method of geodetic surveying by the Federal

Technical Requirements 49 Geodetic Control Committee (FGCC) (1980). Such status should help con- siderably in promotion of more widespread use of this new tool. Adoption of high-precision photogrammetric surveying and inertial surveying should be considered by the FGCC. As pointed out by Brown (1979), other powerful, pertinent developments can be expected to emerge in conjunction with the forthcoming Global Positioning System, projected to achieve full operational status by the mid-1980's. Within the 1980's cost reductions associated with newer technologies can be expected to more than offset effects of wage and salary inflation. This should render increasingly more attractive the execution of large-scale proj- ects of geodetic densification. In addition to horizontal control, there is a need for densification of vertical control. A dense network of second- and third-order vertical control stations will assist the development of a reliable cadastre. For coastal areas the establishment of tidal benchmarks from which a surveyor can determine the high- and low-water lines, is a prerequisite to the division of public from private land ownership and responsibilities. 3.1.2 Horizontal Geodetic Control for Property Boundaries Further densification of the local geodetic system will create a reference framework suitable for boundary control. In both remote and rural areas the existence of evenly spaced accessible geodetic control is essential for the des- ignation of ownership parcels. Bauer (1976) has reported that Racine County, Wisconsin, has established second-order geodetic control monuments at all section and quarter-section corners. State plane coordinates are, therefore, spaced at about 800 m throughout the county. The ten-year program has created a unique blend between the Public Land Survey System and the State Plane Coordinate System. McLaughlin (1975), Ziemann (1976a), and others have recommended spacing of geodetic control monuments, but actual needs should be reviewed and specifications prepared. Much of the responsibility for the densification of the geodetic system will fall to the local land surveyor, who should be familiar with acceptable proce- dures for establishment of additional control points and proper use of geo- detic data. The appropriate state agency, in conjunction with the local profes- sional surveyor/engineer society, should develop strict guidelines for the maintenance and use of this control. The standards for first-, second- and third-order horizontal geodetic control surveys published by the Federal Geo- detic Control Committee (1974) should be the minimum acceptable standards. We recommend that standard practice manuals describing specific survey methods and rules of adjustment for reliable determination of coordinates for

50 NEED FOR A MULTIPURPOSE CADASTRE property boundary corners be made available to the local land surveyor and enforced at each government level. We encourage the establishment of survey data depositories at the county level and the linkage of such depositories with those at higher levels of gov- ernment. 3.1.3 Vertical Geodetic Control Concurrent with increased concern for environment and energy is the need to define land ownership rights in vertical as well as horizontal terms. There are many uses or restrictions that must be described by the third vertical dimen- sion. Three-dimensional coordinates are required to fix air rights, oil wells, mining activity, tunnels, wetlands, flood plains, flood hazard zones, offshore development, solar-energy easements, and other resource or environment- oriented human endeavors. Condominiums are legally described in three di- mensions. Underground utility locations are fixed horizontally and vertically. The U.S. Water Resources Council emphasized that "It should be recognized that flood plains have unique and significant public values, including wildlife habitat of recreational, esthetic and scientific value, open space and ground- water recharge" (Corps of Engineers, 1974). Judge Richard S. Lowe of Pennsylvania, in upholding a flood-plain zoning ordinance, concluded in 1969 that "unbridled freedom of individual choice has resulted in improvident and ludicrous land use patterns which have ob- structed the free flow of surface waters and thereby necessitated inordinately expensive public works or equally expensive disaster relief measures" (Corps of Engineers, 1974). Land-use planning, including flood-plain zoning, depends on a reliable third dimension. It follows that a network of vertical geodetic control monu- ments (benchmarks) is necessary. Classifications and standards for first-, sec- ond-, and third-order levels have been established (Federal Geodetic Control Committee, 1978). Every cadastral agency should establish a lasting network of third-order benchmarks in its district. They should be conveniently located and the data published, to be of maximum use to the surveying engineer. Engineering departments of many cities and towns have established their own local vertical datum referenced to an elevation other than sea level. For construction drawings of public works and particularly underground utilities or subway systems, some organizations find it more convenient to refer eleva- tions to a local datum either to reduce the number of digits in describing an elevation or to eliminate negative elevations. All local datums (except tidal datums) should be tied to the latest National Geodetic Vertical Datum (currently 1929), and the conversion constant from

Technical Requirements 51 the local to the National Datum should be published. This will permit aggrega- tion of environmental data for regional or statewide planning and manage- ment. Established leveling procedures and standards should be followed (Fed- eral Geodetic Control Committee, 1978). We recommend that local vertical datums be referenced to the latest Na- tional Geodetic Vertical Datum. 3.1.4 Tidal Benchmarks The Office of Coastal Zone Management (1978) has recently published a Coastal Mapping Handbook. It states: "Boundaries in the coastal zone range from the limits of private property to the international boundary. All of them are affected to some degree by tidal datums along the coast and along island shorelines. Corresponding boundaries in the Great Lakes area are fixed either by treaty or by acts of Congress, or are controlled by a lake level. Of all these boundaries, those between private and sovereign lands cause the greatest problems." A cadastral survey along shorelines requires a tidal datum in order to deter- mine legal boundaries. Vegetation boundaries of coastal wetlands are depicted on maps and charts requiring horizontal and vertical ground control. The Coastal Zone Management Act of 1972 (Public Law 92-583) declared it national policy "to encourage and assist the states to exercise effectively their responsibility in the coastal zone through the development and imple- mentation of management programs to achieve wise use of the land and water resources of the coastal zone, giving full consideration to ecological, cultural, historic, and esthetic values as well as needs for economic development." Coastal-zone management is currently hampered by the lack of tidal bench- marks. Recent court cases in New Jersey (Porro and Weidner, 1978) as well as the Dolphin Lane Case of Long Island, New York (Greulich, 1978a) have fo- cused attention on the need to define the mean high-water line. The U.S. Su- preme Court in Borax Consolidated, Ltd. v. Los Angeles (296 U.S. 10,1935) established the method for determining the ordinary high-water mark, which is the division between private and public land in states formed from the pub- lic domain. For further reference see National Ocean Survey (1975) and the American Congress on Surveying and Mapping and American Society of Civil Engineers (1972). We recommend that tidal benchmarks be established along the east, west, and Gulf coasts at adequate intervals to permit local land surveyors to define riparian boundaries correctly and accurately.

52 NEED FOR A MULTIPURPOSE CADASTRE 3.2 BASE MAPPING 3.2.1 Large-Scale Maps To satisfy the growing need for integrated land records and information, a system capable of handling a variety of information on a large scale, from the survey base to title transfer, is required. It is also mandatory that fieldwork, data resolution, and information presentation be consistent with the level of land decision making, that of the individual proprietary parcel. This process requires maps at scales significantly larger than those generally available in the United States. Governments now generate some large-scale maps for specific geographic regions and for specific purposes. Large-scale maps (1:500 to 1:25,000) can and should be used for many government purposes, from zoning and planning to identifying forests and wetlands to locating taxable parcels and historic features. The U.S. Geological Survey has undertaken a large-scale base-map use study, which has led to several pilot projects (Scher and South- ern, 1969). To provide large-scale maps for an entire region or for a state will require concerted effort by several governmental jurisdictions. Money for the multi- purpose, large-scale maps could come from savings through elimination of duplication in mapping and information gathering. Resource and environmen- tal information, which is frequently reduced to map display, must be capable of being disassembled to the parcel they cover. This provision is in keeping with the recognition that the status of natural resources is intimately related to the legal interests associated with the ownership parcels. The need for an estimation of the accuracy of land information, referenced to the earth's sur- face, is consistent with the increasing digitization of map-based information, increasing use of geodetic coordinates as a means of carrying map-based in- formation with geo-references, and continuing development of data-processing techniques as the medium for storage of all this information. 3.2.2 Base Maps A base map at a scale of 1:1000 (some planners suggest 1:500 in densely pop- ulated areas) should be created for every urban community. In rural areas with large estates, base-map scales of 1:2000 to 1:5000 may be more practi- cal, while for remote and undeveloped parts of the country scales up to 1:25,000 may be sufficient. This may be accomplished by grid-oriented photogrammetric mapping. New base maps should be tested and certified by a Registered Land Surveyor or photogrammetric engineer to ensure compli- ance with U.S. National Map Accuracy Standards (American Congress on Sur- veying and Mapping and American Society of Civil Engineers, 1972).

Technical Requirements 53 Where available, existing, up-to-date, grid-oriented municipal maps can be used instead of new photogrammetry, provided that they meet U.S. National Map Accuracy Standards. The Massachusetts Land Records Commission has developed guidelines to qualify existing maps for the purpose of assigning land-parcel identifiers (Greulich, 1976). Base maps can be conventional photogrammetric line maps or orthophoto maps. The original base map should be preserved as the basic source map from which all other specialty maps can be derived by either the overlay method or by a digitized computer plot. It is well known that maps become obsolete quickly, and therefore contin- uous updating of the base map should become one of the functions and re- sponsibilities of the cadastral agency. We recommend that base maps be grid oriented, tied to the national geo- detic control system, and updated regularly. 3.2.3 Cadastral Maps The cadastral office that is assigned the task of maintaining the cadastral file described in Section 3.3.3 should incorporate existing and new survey data in its permanent record files. These data, including field notes and survey plans, should be reviewed for accuracy and compliance with adopted cadastral standards. When coordinated and accepted by cadastral standards, existing, recorded plats of land parcels can be plotted on a true copy of the new base map. From it will gradually develop the new cadastral map. During the trans- ition period, it will show many blank spots. But eventually all properties will have been surveyed, reconciled, coordinated, and become plottable. This will follow from the mandatory recording of cadastral surveys. It is essential that this map be updated as new survey data are acquired and reviewed. Since a parcel identifier (Section 3.4.1) will be assigned to each parcel, noted on cadastral maps and referred to on all accompanying documents, each item can be indexed, filed, and retrieved by computers. Besides the par- cel identifier, the cadastral map should depict monuments and such legal lines as property boundaries, easements, public ways, railroad rights of way, trans- mission lines, pipelines, bodies of water, waste-disposal areas, and wetland. The map should show all geodetic control points and official benchmarks identified by number and symbol. To preserve its clarity and simplicity, the cadastral map should not be en- cumbered with such items as coordinates, areas, buildings, and land-related data. These types of information can be stored in computer banks and/or displayed on overlay specialty maps. A wide range of information can be stored in and retrieved from a system that is based on comprehensive, uni- form, and accurate cadastral maps. To be effective, these specialty maps and stored data must be updated continuously.

54 NEED FOR A MULTIPURPOSE CADASTRE 3.2.4 Specialty Maps To attain geometric fidelity on the large-scale cadastral and specialty maps, more-efficient and less-expensive surveys of the ground must be utilized. These maps display such items as the extent of land resources, watershed areas, crop acreage, the results of studies of coastal interactions and change, and boundary surveys for mineral and energy deposits. To limit the expense of new surveys, full advantage should be taken of the vast amount of existing land information and the new technologies available for field surveys. Among these promising technologies are remote-sensing systems and the Global Posi- tioning System. Remote sensing is defined as "The science involved with the gathering of data about the earth's surface or near-surface environment, through the use of a variety of sensor systems that are usually borne by aircraft or spacecraft, and the processing of these data into information useful for the understanding and managing of man's environment" (Williams, 1979). To be useful, the remote-sensing data must have a metric quality consistent with the value of the resource being sensed, the environmental data being monitored, and the survey base being developed. The American Society of Civil Engineers (1979) recognizes the value of metric-quality remote-sensing data and considers it a function of the surveying and mapping communities "to provide geometric fidelity to remote sensing imagery." The Global Positioning System (GPS) will be fully operational in the late 1980's. Williams (1979) has described the great potential of remote-sensing technology, particularly when the GPS receiver is combined with an inertial surveying system, as a powerful tool that will dramatically improve "the con- tributions that state, county and municipal engineers and surveyors can make to our national goals by integrating remotely sensed source materials into feasibility studies, long-range projections and possibly, even basic decisions processes." These new technologies tend to produce large quantities of data. The effi- cient use of computerized data banks will make this avalanche of information manageable, provided the data are properly evaluated and organized. In a well-functioning multipurpose cadastre, such data can be stored, retrieved, and manipulated at relatively low cost. The printed cadastral and specialty maps then can be rapidly revised and maintained current. 3.3 CADASTRAL PARCEL 3.3.1 Definition of the Cadastral Parcel A cadastre requires a fundamental unit of land—a cadastral parcel. This unit of land becomes the basic building block for maintaining land information,

Technical Requirements 55 including the information about rights and interests. An ideal building block is any common and natural reference for land information and a division of the earth's surface whose location and boundaries are known and maintained. A cadastral parcel is an unambiguously defined unit of land within which rights and interests are legally recognized. Therefore, the cadastral parcel en- velops a contiguous area of land with a history of legal interests (McLaughlin, 1975). The cadastral parcel for a multipurpose cadastre is that unit of land for which there is a unique and complete bundle of rights. Public lands, railway, highway, and utility corridors, as a matter of convenience, may also be par- titioned into cadastral parcels. This concept of a cadastral parcel has been for- mulated by Robert N. Cook: A parcel is a (continuous) area of land described in a single description in a deed or as one of a number of lots on a plat, separately owned, either publicly or privately; and capable of being separately conveyed. For ease of indexing data, a segment of a street, highway, railway right of way, pipeline, or other utility easement may be treated as though it were a parcel (Moyer and Fisher, 1973). To determine where the boundaries of a cadastral parcel so defined actu- ally fall on the land may require a sorting out of various other interests in land that are legally recognized. The boundaries of these other interests may or may not be coterminus. The primary type of interest, for this definition, is land ownership, associated with that set of rights and interests that may be acquired and transferred. Normally one cadastral parcel will include all land to which one complete bundle of rights may be assigned. However, in certain cases it may be necessary to demarcate only that land associated with a subset of rights, such as an easement. For some types of data in a multipurpose system, special overlays with other types of additional boundaries may be needed. Land operation, for ex- ample, may be associated with units of land for which there is a uniquely recognized use or management of land resources. An agricultural operation is such a unit. 3.3.2 The Role of the Cadastral Parcel The role of the cadastral parcel in land-information systems is indicated by an examination of existing cadastral systems. Cadastral systems are generally classified according to the nature of infor- mation maintained in the individual files, registers, or subsystems. These data files contain juridical, fiscal, public-land-use and regulation, special assessment, and resource and environmental records. Juridical (Title) Records are the records that determine the legal interests

56 NEED FOR A MULTIPURPOSE CADASTRE in land. They are established by statutory and common law regarding estates in land, real estate and survey practice, and related activities. These records are organized according to a unit of land within which a set of rights and interests are recognized and held by a defined person, persons, or corporation. A parcel of land held in fee simple is an example. We recog- nize such a unit as the individual proprietary parcel. Title information in the United States is generally obtained from a system described as rudimentary deed recordation. Because recording does not in it- self effect transfer of title, legal methods have evolved to assign priorities to evidences of transfer. The essence of these methods and the use of public registries are associated with doctrines of notice. These doctrines have led to indexes, both grantor-grantee and tract. However, the nature of these public systems creates a privilege held by lawyers, title examiners, and insurers hi the drafting and warranting of title documents. Parcel boundary information is distributed throughout title documents and in the files of surveyors. Occasionally, the information is reduced to graphical form and deposited in a public registry. However, there is generally no specific repository or file for this information. Thus the parcel boundary record is less well developed than that of the record of interests. Fiscal (Assessment) Records should contain the information needed for equitable and efficient valuation of land. They also provide for the contin- ued assessment of improvements to land. The fiscal parcel and record are characterized by an "assessable parcel of land" and by the information used to produce a valuation of this parcel. In most cases the parcel for fiscal rec- ords is the same parcel as for juridical records. The nature of the title or interest record system has influenced the system of assessment records. Frequently, ownership information for valuation pur- poses is compiled by assessment officials. The assessment offices have become the primary source of maps of property parcels, although such maps for de- fining parcels for purposes associated with a knowledge of rights and interests are not always sufficient. Thus, despite their unique responsibility, rooted in the valuation function for maintaining comprehensive data on the entire inventory of land parcels, tax officials often have a limited need for strictly ownership information. They need resource, environmental, zoning, and special assessment informa- tion, and they need to relate that information to well-defined parcels. After that, they need the name and address of a person to whom they can success- fully send a tax bill. Public-Land-Use and Regulation Records are statements of society's inter- est in land. As zoning laws or building codes they typically appear as state- ments about land use for a parcel or as standards for an area of land that may encompass a number of land parcels.

Technical Requirements 57 Zoning and planning officials are concerned with well-defined parcels and with the associated rights and interests. They are concerned with boundary changes and other activities that may influence land activities. Their need for information encompasses all activities, legal and otherwise, which enables them to plan properly and to oversee compliance with existing law. They rely on many maps as sources of information, but they also need additional infor- mation, such as the recording of a subdivision, in order to monitor compli- ance with zoning laws. Zoning and planning offices are also important sources of information about rights and interests in parcels of land. However, zoning restrictions are not considered part of the record of encumbrances on land for title purposes. Yet these restrictions are often as important or more important to the tradi- tional title than the privately arranged encumbrances. It remains a difficult task to assemble a complete picture of the rights and interests in a parcel from the many separate juridical and public land-use and regulations records. Infrastructure Records include those for highways, sewer lines, transmission lines, and similar parcels, which are divisions of land often carved from larger property parcels. Property law expresses the relationship legally in such terms as appurtenant or restrictive easements. The parcels that sustain such ease- ments may be described independently, but a symbiotic relationship exists between the two. The infrastructure records are widely dispersed. They have come to be the property of various public and private agencies. It is often difficult to deter- mine who has the records for a particular parcel, even after determining that such records exist. Public and private utilities spend large sums of money to acquire, assemble, and store infrastructure records (Clapp and Niemann, 1977). Resource and Environmental Records are typically concerned with the na- tural division of land that may not necessarily coincide with the individual land parcels. Examples are records of soils, water courses, land cover, waste- disposal sites, and wetland. These resource and environmental records can be and often are maintained without reference to man's divisions of the land. A map is the most common expression of these records, whether in a traditional map form or in the form of geo-referenced information. The demand for resource and environmental information has led to a great expansion in these data files. This activity is related to the increased aware- ness of man's relationship to and influence on the natural world. This inter- relationship between man and the environment leads to the need for resource and environmental information at the ownership or property parcel level. For example, management of surface and groundwater systems relies on a knowl- edge of the natural water courses and networks, which depend only on the

58 NEED FOR A MULTIPURPOSE CADASTRE natural division of the land; their management also depends on a knowledge of the legally recognized riparian rights of landowners, which depend on the property parcels. Another environmental concern that can be related to the property parcel is that of water pollution. In a subject-area oriented society, it is no wonder that a vast array of phys- ical, resource, and environmental information is collected, assembled, stored, and disseminated with little coordination among agencies. Common defini- tion of terms, formats, map scales, notation, and related items are rare. Each agency proceeds according to its own perceived needs and efficiencies. Fre- quently, resource and environmental information is collected without a clear understanding of how it is to be used for purposes of planning or administra- tion of regulations. These purposes and existing records systems point to the need to relate resource and environmental information to a fundamental unit of land—the individual property parcel. It is the unit used for many records and for which land decisions are made or implemented. Thus references to the property parcel are required for information related to both natural and man-made land divisions. This is the only choice that imparts to the system the stability associated with the legal process. The choice of an arbitrary cell of land, as has been made for some land-information systems, creates an in- herently unstable system, although at lower cost in the short run. This choice fails to recognize the ultimate use of land information in land planning by failing to recognize the importance of the rights and interests held by the land owner. 3.3.3 Delineating the Cadastral Parcels Legal and survey practice are crucial to the description of a cadastral parcel. Both the nature of the interests associated with the land and the spatial ex- tent of these interests and of natural features of the parcel must be defined. The legal and surveying practices, and the records that result, are a func- tion of many factors, many associated with ancient tradition. A detailed dis- cussion of required improvements in the legal regime of title records is beyond the scope of this report. It is a subject under investigation by many groups, including the American Bar Association (Chatterton and McLaughlin, 1975). Suggested improvements include those associated with the proposed Uniform Simplification of Land Transfer Act (National Conference of Commissioners on Uniform State Laws, 1977), Marketable Title and Curative Acts (Basye, 1970), title registration (Shick and Plotkin, 1978), and others. The physical delineation of the cadastral parcel depends on surveying law and practice. A survey process for parcel delineation includes the following steps:

Technical Requirements 59 1. Gathering of information relating to parcel boundaries, 2. Analysis of this information, 3. Establishment of boundary markers on the ground, 4. Assignment of official identifier numbers to each parcel and recorda- tion or registration of parcel identifier numbers and boundary information, 5. Storage of the parcel inventory and boundary information, and 6. Dissemination of this information (McLaughin, 1975). The first three steps constitute a legal survey as the term is now under- stood. We recommend that there be created a new cadastral file containing the records of boundary information referenced to the identifer number of each cadastral parcel. The file could be maintained as a separate file of information, as an addition to existing files, or in the form of references to boundary infor- mation in existing documents. A well-defined file of boundary information can be an object of attention and assurance similar to the attention and assur- ance given the file of title information. We recommend improvements in survey and boundary law giving greater priority than now exists in the use of coordinates for boundary descriptions. A coordinate description of parcel boundaries does not necessarily replace the use of natural and artificial markers. Markers continue to provide physical awareness of the boundaries. When a marker is lost, the coordinate system, supported by all other monumented points, provides the relocation and re- placement mechanism. 3.4 MECHANISMS REQUIRED TO SUPPORT MULTIPURPOSE DATA SYSTEMS The technical requirements for the multipurpose cadastre system were out- lined above (see Sections 3.1-3.3). These requirements were stated in terms of the three basic components of the multipurpose cadastre: reference frame, base maps, and cadastral overlay (see Figure 1.1). This section presents several additional requirements necessary to link various parts of the cadastre. The discussion here is limited to linkages between only two levels, the cadastral overlay and various land-record files (registers) that make up the multipurpose cadastre system. Ways of integrating among the various land- record files, both within a unit of government (at one level) and among vari- ious levels of government, are also included. Linkages between the reference frame, base maps, and cadastral overlay are covered elsewhere.

60 NEED FOR A MULTIPURPOSE CADASTRE 3.4.1 Integrating Mechanisms: Standard Indexing and Referencing Systems The overriding integrating mechanisms needed for successful implementation and operation of multipurpose cadastre systems are standards, indexing, and referencing systems for data. The mechanisms apply specifically to standardi- zation of terms, procedures, and data storage units throughout the multipur- pose cadastre. A number of these critical standardized items are included below. Parcel Unit. As a general rule, the basic unit for data handling is the cadas- tral parcel. In most cases, the cadastral parcel is isolated on the basis of sepa- rate ownership, as described in Section 3.3.1. Parcels that are capable of transfer to another owner are the most common example. Parcel Identification. A number of systems are used to identify parcels in the land data files currently maintained by governmental units. While each of these identifier systems may be adequate for a given governmental depart- ment, the existence of several noncoordinated systems often prevents the widespread use of the land data. Therefore, to ensure data coordination and facilitate multiple use of data files in the cadastre, each parcel should be iden- tified by a unique number. It is important that the cadastral system provide not only for the unique parcel identifier but also for the continued use of other systems used at pres- ent to identify parcels and related land data. Therefore, cross-indexing tables should be included so that users can access the cadastre, using procedures with which they are familiar. (Street address and block and lot number are examples of land data identifying systems that are used by many local gov- ernment agencies.) The geocode is one example of a unique numbering sys- tem that makes possible the integration of data from two or more data files within a local government or between two or more local governments. A computerized index of parcel identifiers will assist in linking data from various files. It will also vastly improve the ability to retrieve data from indi- vidual files, particularly in land-title recording offices. To assure and facilitate the use of the unique parcel identifier, each parcel identifier number in the land-parcel register should become the official, legal reference to all title documents affecting that parcel, that is, the general index number used by the recorder of deeds, at least for all documents filed on or after the date the register becomes available. Such use of the parcel identifier would be sufficient for legal descriptions of parcels, as proposed in the Uni- form Simplification of Land Transfers Act (National Conference of Commis- sioners, 1977). The lack of a parcel index in many parts of the United States is one of the primary shortcomings of the present system of land conveyancing. Grantor-

Technical Requirements 61 grantee indexes (arranged alphabetically by the name of the seller and buyer) are inefficient tools for locating records pertaining to a particular land parcel. To overcome this inefficiency, many counties are now using a tract index that groups all records for a particular parcel on one page of an index. Title insur- ance companies that maintain title plants are also organized by the tract in- dex system (Moyer and Fisher, 1973). A substantial volume of literature has developed concerning the design and administration of "the ideal" parcel numbering system (e.g., Moyer and Fisher, 1973; Ziemann, 1976b). Selection of a specific reference system should probably be left to the individual states. This flexibility in design is de- sirable in order to adapt most easily the parcel number to existing files and practices of each local cadastral jurisdiction. The power of modern computers makes it possible to relate parcel records across several jurisdictions having different numbering systems. Parcel Locator Numbers. Many land data files include a single number giv- ing the geographic location of a convenient point within the parcel, typically the "center" as determined visually. These may be referred to as parcel geo- codes and typically express the coordinate location of the chosen point to the closest 10 feet or 1 meter. A listing of geocodes for each parcel will facilitate graphic displays of parcel data, sorting of parcels into large regions for analyt- ical purposes, location of individual parcels visually on a map, and various other procedures. Some localities have chosen to use geocodes as the unique parcel identifier numbers. The advantages of the geocode parcel identifiers probably exceed the disadvantages because of possible need for changes in the code due to resurveying, remapping, and datum readjustment. Parcel Description. As the multipurpose cadastral system evolves, a coordi- nate-based description of each parcel should be added. The coordinate system used for description purposes ideally should use the same coordinate system as is used for parcel location. Uniform Data Identification. All relevant parcel and parcel-related data should include the unique parcel number as one of the identifiers for all such data. Data files for which such identification are important include title, assessment, land-use controls, land-use planning, and environmental protec- tion. Local offices responsible for these data files should be linked electroni- cally. This will improve efficiency of government since the impacts of changes in one data file often impact on the data file and/or work activities of another office. Also, such interoffice linkages will facilitate a rapid, accurate response to citizen requests for information that requires retrieval from two or more data files. The use of parcel numbers for indexing title records is central to the model recording system published recently in the Uniform Simplification of Land Transfer Act (National Conference of Commissioners on Uniform State Laws,

62 NEED FOR A MULTIPURPOSE CADASTRE 1977) and also is a required element of all seven of the model land-title- recording systems being demonstrated by the U.S. Department of Housing and Urban Development, under Section 13 of the Real Estate Settlement Pro- cedures Act of 1974. By requiring that the identifier number be indicated on all documents recorded, the recorder of deeds is able to spot the creation of any new parcels that did not previously exist. This will trigger the updating of the register itself and also will help in the enforcement of local subdivision control requirements. Parcel Index Map. A map showing parcel boundaries and parcel identifying number should be available in each local government office containing land- record files. This map index will assist in both the filing and retrieval of parcel data and be particularly useful to citizens attempting infrequent retrieval of information. Nonparcel Data Links. The locations of many of the natural attributes of land that are critical for land management bear no particular relation to land ownership and must be described by boundaries determined independently of cadastral parcels. Examples of these attributes are listed in Section 2.1.3. Nevertheless, the interactions of such phenomena, and their changes over time, with individual land ownerships must be considered in the use of re- source and environmental records, as explained in Section 3.3.2. This will be possible only if the boundaries of both the cadastral parcels and the natural divisions of the land are located using the same coordinate system. This per- mits a visual display of the natural areas that fall within each parcel by over- laying the separate sets of boundaries, either with transparent map sheets or by a computer plot of the digitized boundary locations. It also permits cross- indexing of the natural areas present in each cadastral parcel, or vice versa, as needed. However, cadastral parcels should not be used as the units for analysis or computations of natural phenomena but only for presentations of the results of such analyses and their implications for land owners. Cadastral parcels can only provide rough approximations of the geographic distribution of natural phenomena and may be totally inadequate for this purpose in more remote areas where the individual ownership parcels typically are large. The technology of analysis and presentation of environmental data has been revolutionized by computers and software that became available in the 1970's. The methods of comparing data that relate to different geographic breakdowns of the same land area are a major subject of study for the new field of land-information science described in Section 4.3.7. 3.4.2 Quality Control In order that users of the multipurpose cadastre be confident about system content, it is important that standards of quality concerning file content be

Technical Requirements 63 clearly understood. Such confidence is necessary both to obtain cooperation on data-maintenance activities and encourage use of available data by all po- tential users. Such quality-control standards should include spatial accuracy as well as the validity of specific data items. Therefore, some minimum standards are required for data and information to be accepted into the system. This does not necessarily impose criteria for identifying acceptable data. Rather, the data themselves should carry the qualifications or limitations on how they can be used. Responsibility for assigning limitations may reasonably rest with the unit that introduces the data into the system. 3.4.3 Privacy and Confidentiality Safeguards To ensure maximum integration of information through linkage of data files, a clear understanding of how and why data are or are not available to all sys- tem users is imperative. The problem of confidentiality can be met if the land-record system is defined to include only information that is public. Pub- lic information should be accessible and correctable by the individual. Confi- dential information remains in the possession of agencies traditionally respon- sible for such information. This information can be segregated and protected from the common and accessible land records in the information system. In some cases, aggregations of specific and confidential information may be introduced into the public record, but the specific information remains con- fidential and separate. 3.4.4 Phased Implementation The complete development and implementation of any comprehensive land- information system should proceed gradually. This is true both in regard to elements in the system and to the area covered by the system. Fully imple- menting or phasing in the system within any region or state may take several decades. Gradual, phased implementation is necessary, too, because the legis- lative and budgetary processes of local, state, and federal governments tend to address short-term, readily identifiable problems rather than long-range, inter- governmental improvements. Implementing a comprehensive land-informa- tion system requires foresight, commitment, and cooperation among our legislative and agency officials. Prototypes for interim cadastral systems that can serve during implemen- tation periods are outlined in Section 4.4. 3.5 IMPROVEMENTS IN SURVEYING PRACTICE The material that follows sets forth specific problems in surveying practice that require improvement in order to delineate physically the cadastral parcel.

64 NEED FOR A MULTIPURPOSE CADASTRE These problems are identified so that the reader who is a nonsurveyor may sense the importance of higher standards in surveying for the development of a multipurpose cadastre. Specific standards for improved practice are indi- cated. 3.5.1 Accuracy Standards Accuracy standards for property surveys should be established. These stan- dards should be based on need, both present and anticipated. However, need is most difficult to establish, as its importance to present land owners and present land-use managers may become obsolete with changes in ownership and changes in local administration. A new owner's or a new administration's intended use of the land may increase or decrease accuracy requirements. In addition, for example, development of surrounding land, building of a new highway or a new power line, or establishment of a new industry in a town can have an impact on all properties, not only those directly involved. Al- though such changes are difficult to predict, a cadastre must allow for them and the improved accuracy required in parcel delineation engendered by changes in land use. The responsible cadastral agency at the local level should anticipate the public's needs for accurate property surveys. Individual consumers or users of land generally do not appreciate the difficulties involved in making accurate measurements. Because property boundaries are subject to both mathematical and legal scrutiny, unrealistic accuracy expectations must be avoided (Greulich, 1977; McLaughlin et al., 1977). It is imperative that practical, but lasting, standards of accuracy be set. It will take vision and the expertise of the sur- veying professional to implement these standards, and it will take vigilance and perserverance of the cadastral agency to enforce and maintain them. We recommend that the surveying community, through its professional so- cieties, with the cooperation of the local cadastral agencies, undertake the establishment of reasonable and practical standards of accuracy. These stan- dards should, as a minimum, meet those advocated by the Federal Geodetic Coordinating Committee. 3.5.2 Monuments and Coordinates Originally the legal description in a deed was a means to an end, enabling the reader to retrieve corner monuments of a land parcel. Monuments or land boundaries were thought to be permanent and everlasting. Over 300 years of land use in the so-called metes and bounds states has proven otherwise. Any monument is subject to destruction or disappearance. In time, the written description survived as the only source of evidence for many parcels of real

Technical Requirements 65 estate. In the absence of an integrated survey system, this led to what has been called the "floating island disease" (Greulich, 1978b; 1978c) of properties. Written legal descriptions of common boundaries of abutting parcels do not always lead to the same corner. Quite often they are deliberately vague or in direct conflict with each other. Mulford (1912) deplored "that the original record, while an invaluable general guide, is only approximately accurate." The situation has not improved much in the intervening years and, although Thompson (1976) and others have predicted that the land surveyor of the twenty-first century "will discard his transit and electronic distance measure- ment equipment" and replace them with a hand-carried inertial package, the need for careful ties and adjustment into geodetic control will not be elimi- nated. In addition, at some stage of a boundary survey, the surveyor will con- tinue to have to walk the land in order to determine legal corners mathemati- cally or to mark legal corners physically. Among the metes and bounds states, it appears that the Massachusetts Land Court is the sole agency that since 1898 has regularly decreed property boundaries binding on both petitioner and abutter. A decree is issued by this court for every parcel registered; the decree is based on surveys made in ac- cordance with strict Massachusetts Land Court instructions (Woodbury, 1971). Monumentation is one of the requirements. Because land court registration of land has remained voluntary, it, too, created islands of good surveys, perhaps less floating, but too isolated to be of significant value to the public. In the public-land states, cadastral surveying has been a method of "perma- nently" defining the boundaries of land by establishing monuments on the ground and identifying their locations in field notes and plats (Bureau of Land Mangement, 1978). Although the permanence and inviolability of cor- ner monuments is generally recognized, the Bureau of Land Management's experience shows that vast numbers of marked points have been obliterated or lost. Nevertheless, physical monuments of legal status are an absolute neces- sity in the lawful and peaceful use of the land. The Bureau of Indian Affairs reported that the lack of legally established physical boundaries in many areas of its jurisdiction "is having an adverse im- pact on Indian resource development" (Committee on Appropriations, 1979). Similar problems affect lands owned by local, state, and federal governments. Standards should ensure that only one monument for each corner retains legal status. A distinction between so-called permanent, semipermanent, and temporary monumentation must be made. Establishment of standards would help to avoid the pitfalls of the past. Therefore, we recommend that 1. Permanent monuments be set when surveying new lots. 2. Permanent monuments be set at previously unmarked or insufficiently marked corners during resurveys of existing properties.

66 NEED FOR A MULTIPURPOSE CADASTRE 3. Monuments be officially recognized by all interested property owners. 4. Coordinates for all monuments be determined. 5. Local cadastral agencies be empowered to enforce protection and main- tenance of monuments. 6. Public works departments in cooperation with the cadastral agency make provisions in their specifications and contracts that would prevent de- struction or enable accurate replacement of monuments. Unfortunately, monuments provide only partial security for a land-records system. Even collateral evidence, although helpful and often necessary, is no guarantee that an original corner is reproduced in its exact and true original position. Horizontal coordinates are needed not only for identification, index- ing, and aggregation of data but also for retrieval, recovery, and replacement of boundary lines. They will bring true permanence to the system. Even if large numbers of monuments are lost, a well-placed geodetic control system will enable the surveyor to replace them accurately. The recent abandonment of railroad right of way and removal of railroad tracks has caused a serious and consequential loss of legal "monuments" for many north central states. Even at this late date, coordination of existing "monuments" could avert ex- pected future losses. McEntyre and McNair (1963) recommended that co- ordinates of all township corners be established by first-order methods and all section corners become second-order geodetic control stations (Federal Geo- detic Committee, 1978). They also stated that in the description of real prop- erty, State Plane Coordinates "can be made more definite, certain, and mate- rial than other systems." The Bureau of Land Management, long ago, recognized the value of includ- ing coordinates in their data files. Mining claims and irregular land lines are frequently tied together and depicted on "Connected Sheets" for clarification (Bureau of Land Management, 1978). Although these diagrams have no legal status, they are, nevertheless, an important working index tool (Meek, 1971). The greatest weakness of the Public Land Survey System is the failure to provide monumented points in a coordinate system that is connected to the national geodetic network. In a recent study, the Bureau of Land Management (1979) found that "there is a need to more closely integrate the Cadastral Survey program with other national geodetic and mapping reference systems." The use of coordinates tied to a national network offers a means for offset- ting the physical vulnerability of legal corners. Upon completion of the new adjustment of the geodetic horizontal con- trol network of North America in 1983, the National Geodetic Survey, U.S. Department of Commerce, will publish new latitudes and longitudes for all control points. For each of these points, State Plane Coordinates and Univer- sal Transverse Mercator Coordinates (Standard 6° Zones) will be available in meters. Surveyors and government entities can obtain assistance in the use of these coordinates from the National Geodetic Survey.

Technical Requirements 67 We encourage cadastral agencies to plan for the use of State Plane Coordi- nates or Universal Transverse Mercator Coordinates in describing monuments and property boundaries. 3.5.2.1 Connections to Geodetic Control Points It will be necessary to prescribe detailed methods for connecting boundary points to geodetic control points. All boundary points should be connected to at least two geodetic control points through closed loops. Figure 3.2 de- picts examples where new boundary points (circles and black squares) are properly connected to two or more geodetic control points (triangles), where- by the accuracy of the boundary survey can be checked. Open-ended spur tra- verses and one-sided connections should be avoided. Figure 3.3 depicts ex- amples where new boundary points (circles and black squares) are connected to only one geodetic control point (triangle), which does not permit an ade- quate check on the boundary survey. Whenever possible, monuments should be set before undertaking the sur- vey connection to the geodetic control point and before computing their co- ordinate values. The setting of monuments at predetermined positions is a frequent source of errors and should be avoided. For property under construction, the survey should originate at an off-site third- or higher-order geodetic control point (Federal Geodetic Control Com- mittee, 1978) in order to minimize loss of a critical point during construction. With assurance that this geodetic control point will not be disturbed during construction, the replacement of property corners, without having to rely on questionable deed descriptions of abutting lands, would be facilitated. In addition, the connection of the local survey to two or more geodetic control points will enhance the legal status of this survey. In time, metes and bounds could be deleted from the legal description; one need only to refer to a parcel identifier of a well-established land-records system. This would save time and money and would eliminate a frequent souce of errors. 3.5.3 Evidence Accurate record keeping can resolve the age-old question of primary evidence. Which should carry more weight, coordinates or monuments? Neither should be "primary" by or in itself. In the past, the problem has not been monuments versus coordinates but rather monuments versus improperly determined co- ordinates, improperly determined both during the original and the retrace- ment survey. If monumented and coordinated geodetic points are the founda- tion for the original legal description of a parcel of land, the surveyor's field notes are of great importance. If these notes indicate that a monument has been set based on predetermined coordinates in a subdivision, the coordinates

5km 3td OR 2nd ORDER GEODETIC CONTROL POINT (TYR) RURAL I I km SUBURBAN/RURAL . -. - A PARCEL 1 , 8 ! 300m URBAN/SUBURBAN FIGURE 3.2 Examples of acceptable ties of boundary control to geodetic control points. 68

3rd OR 2nd ORDER GEODETC CONTROL POINT (TYR) PARCEL FIGURE 3.3 Examples of unacceptable ties of boundary control to geodetic control points. 69

70 NEED FOR A MULTIPURPOSE CADASTRE will carry less weight than if the existing monument is resurveyed and its co- ordinates determined in accordance with acceptable practices; the location of an undisturbed monument will have greater acceptance because of the small differences in coordinates one could expect to determine from a resurvey. The significant advantage of coordinates is evident if a monument is lost or destroyed. The surveying profession has not established a rigorous approach to the computation of monument coordinates in common boundary surveys, a re- quirement that is essential for a comprehensive cadastral system to be effi- cient. Mulford (1912) noted that the surveyor's most difficult task is often "to find the land" to be surveyed. He also stated: "Surveys, when made, were very crude, little attention was given to the establishment or the maintenance of boundaries. Loose, faulty and ignorant conveyances, the use of perishable landmarks or no landmarks at all, the temptation to build fences 'offline' for a dozen reasons, good and bad, and innumerable other things have conspired to render the boundaries of land the most uncertain of all things." Many of the same problems are inherent in boundary surveys today. The question of monuments versus coordinates was considered by a joint committee of the American Bar Association and the American Society of Civil Engineers (1941). They reported: Many lawyers place great reliance upon the old maxim that metes and bounds control courses and distances. They ask if the use of plane coordinates will interfere with the application of this maxim. In answering this question, the engineer must first consider the fact that the maxim is not recognized by the courts to the same extent as in the past. The tendency of judges is not to be bound by fixed rules when they lead to absurdities upon the facts before them. They are likely to believe that such absurdities can better be avoided by considering the particular facts. Courts have adopted a more flexible doctrine, that where there is a dispute in the description of real property, that which is more defi- nite, certain, and material will control. The application of coordinates to section corner monuments in the State of Wisconsin has served to "perpetuate and revitalize" the long-established, but badly neglected, Public Land Survey System (Bauer, 1976). Once the surveying profession adopts standards of accuracy (see Section 3.5.1) the arguments over monuments and coordinates as primary evidence will disappear. 3.5.4 Recorded Plats and Plans The assembly of the cadastral map will start with the many plats and plans already on file with registries of deeds, county courthouses, and other public repositories. Since a resurvey of all parcels of land will be impossible, selective use of existing information is mandatory. Starting with recorded plats or

Technical Requirements 71 plans, a distinction must be made between "compiled" plans of record and plans based on a field survey. We now define various types of existing information that might be included on the cadastral map. Compiled Plans have no claim on accuracy or reliability. They serve as gen- eral information only and, if included in the cadastre, should be maintained current, but assigned a low order of accuracy. Survey Plans of single lots may conditionally be incorporated in the multi- purpose cadastral system; property lines are subject to final determination and reconciliation by field surveys in accordance with cadastral standards to be issued. Title Insurance Plans would fall into the latter category. Subdivision Plans, which are based on field surveys, can be partially ac- cepted, providing no major errors that could cause legal complications are dis- covered. All interior lot lines can, on verification, be fully incorporated in the new cadastre. Perimeter lines and corresponding perimeter lots should be treated like survey plans and be reconciled in the field before final acceptance. There are two unique boundary-survey evaluation programs that should be emulated by all cadastral agencies—those of the Bureau of Land Management (BLM) and the Massachusetts Land Court. Boundaries and plats that are based on the official cadastral survey and accepted by the BLM and boun- daries determined by decrees of the Massachusetts Land Court can each be in- corporated in a cadastral system without further verification. The multipurpose cadastre will thus have started with three types of boun- dary data: final, conditional, and temporarily undefined (based on deeds without survey plans). Following the lead of the Modernization of Land Data Systems (MOLDS) II conference (North American Institute for Modernization of Land Data Sys- tems, 1979), we recommend that 1. Lawyers and surveyors promote state legislation that would make the recording of survey plans for conveyance or subdivision mandatory; all new deeds be based on a reliable survey, similar to those required by the plat laws or section corner filing acts that exist in some states; and the American Con- gress on Surveying and Mapping and the American Society of Civil Engineers propose model standards. 2. Title insurance companies agree that all future policies be accompanied by a survey plan; and the American Land Title Association and the American Bar Association propose model standards. 3. All title insurance surveys be recorded for the benefit of abutters and future users; and the American Bar Association and the American Land Title Association propose model standards. 4. All boundary-survey plans show deed references of land owners and adjacent land owners until a parcel identifier system has been adopted.

72 NEED FOR A MULTIPURPOSE CADASTRE These interim but immediate steps would assist in the construction of a cadastral map. They would be of substantial benefit to the future cadastral system, without adding a burden on the taxpayer. 3.5.5 Field Notes Another prerequisite to reliability will be the mandatory filing of field notes, either originals or certified copies. Many plat filing laws in the public-land sur- vey states, as well as the Massachusetts Land Court, require that ties to exist- ing monuments be shown on the recorded plat or document. That is not suffi- cient. A plat or plan is a third-generation document. In fact, it is largely the product of a draftsman—a survey technician. The original and first document of boundary records is the surveyor's field notes. His worksheet or computer printout is the second-generation docu- ment. The final plat or plan is a summary that depicts the surveyor's findings and conclusions in a form more presentable than the field notes. The Bureau of Land Management (1973) in its instruction manual empha- sizes the "importance, or legal significance, of the plats and field notes" by referring to an opinion by the Department of the Interior (45 L.D. 330, 336) based on a decision of the U.S. Supreme Court (Cragin v. Powell, 128 U.S. 691,696). The Court said: "It is a well-settled principle that when lands are granted according to an official plat of the survey of such lands, the plat it- self, with all its notes, lines, descriptions, and landmarks, becomes as much a part of the grant or deed by which they are conveyed, and controls so far as limits are concerned, as if such descriptive features were written out upon the face of the deed or the grant itself." In light of this decision, the cadastral agency should require the recording of the surveyor's, both government and private, original field notes together with the to-be-recorded plan. The field notes should be cross-referenced by parcel identifier and made available to other surveyors and the public. The notes will enable the agency to verify and check the surveyor's work. It will be necessary to adopt minimum standards for field notes. They serve to sup- port a permanent public record and should be certified by the registered land surveyor responsible for the survey. We recommend that the cadastral agency adopt minimum standards for field notes and mandatory filing thereof. 3.5.6 Surveyor's Plan For all new surveys and subdivisions, the surveyor should submit to the cadas- tral office a certified plan of land showing all monuments found and/or set and indicating those monuments whose positions were held fixed in the sur-

Technical Requirements 73 vey computations. Their precise mathematical relationship to each other and to the official state-adopted coordinate system should be shown. Distances, angles, bearings, or azimuths between corners should indicate their compli- ance with official tolerances. The plan should clearly identify all survey lines and geodetic points used to determine boundaries. It must show the official parcel identifier of an ownership parcel as well as that of the abutting proper- ties. The plan should be similar to that currently required by title insurance companies or by the Massachusetts Land Court, with enlarged subsketches for critical dimensions and offsets. Previously determined boundary data that have been officially accepted by the cadastral agency must not be altered, if they fall within recommended tol- erances. Deviations found should be shown, together with the applicable max- imum tolerances. Reconciliation of existing boundaries or the creation of new boundaries should take place in the field. Where abutting deeds remain in conflict, an ad- ministrative procedure, based on a physical examination of the property, should be available to resolve the issue. The plan should be accompanied by a certified calculation sketch or work- ing drawing indicating thereon all new measurements as well as all dimensions and angles found in various old plans and deeds of record. This will enable the cadastral officer and future surveyors to better understand and verify the present surveyor's conclusions. For clarification, it may be necessary to include a control diagram on a separate sheet. A computer printout of relevant calculations, as well as certi- fied field notes, should accompany the plan. The registered land surveyor should sign and seal his plan together with a certificate that the survey was done by him in accordance with current cadas- tral standards. 3.6 PUBLIC AND PRIVATE UTILITIES CADASTRE "The multiplicity of utility ownership and competition leads to many con- flicts for space," reported the American Public Works Association (1974). Lack of reliable underground utility location information is considered a "na- tionwide problem." A survey on the status of municipal utility records re- vealed that only 35 percent reported complete and up-to-date records, and only about half of those reflect as-built conditions. A joint American Public Works Association and American Society of Civil Engineers (1974) committee concluded that "problems have arisen over safe and economical allocation of utility location space because of lack of effec- tive coordinated practices by, and between, privately and publicly-owned utilities." The committee recommended the adoption of a broad information

74 NEED FOR A MULTIPURPOSE CADASTRE retrieval system and the creation of both a street master file and a parcel mas- ter file and also concluded that compatibility of scale and "regular exchange of base maps" would "facilitate coordination." Today, we know that the cadastre will accomplish this coordination automatically. There is no reason why the multipurpose cadastral base map cannot fulfill the needs of the utility industry. Earthquakes in Alaska and the Great Bliz- zard of 1978 along the New England coast have shown the urgency of know- ing exact locations of these lifelines of our society. Increased use of plastic pipe has rendered metal detectors ineffective. Cooperation between public works departments and cadastral agencies could achieve safe and economic utilization of space. Channels of prompt communication between these two important agencies must be established. Specifications for construction of underground utilities should provide for measuring and locating of as-built structures before backfilling of trenches. The cadastral office should develop standards for connecting surveys to hori- zontal geodetic control points and the national vertical datum. As-built loca- tion plans at a scale compatible with the official cadastral base map should be prepared and certified by a survey engineer. Surface structures, such as manholes, catch basins, gate covers, hydrants, and utility poles should be identified by street and State Plane or Universal Transverse Mercator Coordinates, numbered by utility, indexed, mapped, and filed in the data bank. Accuracy standards for the location of each utility may vary but should be standardized. Location cards (generally called tie cards), which display hori- zontal and vertical positions and measurements to relevant objects and sketches, should be simple but effective for retrieval and quick recovery on the ground. Current tie cards for underground utilities are often useless be- cause they were prepared by workers untrained in the art and science of mea- surements. Ties to opposite markers or to temporary structures should be avoided. Additional ties to geodetic control points are as beneficial to utili- ties as they are to property owners and land-management organizations. Cadastral agencies must set rules in cooperation with public works depart- ments and utility companies that will assure constant and accurate updating of the utility map. Only thus will it be possible to protect lives as well as pro- vide space for additional life lines so vital to our future. We recommend that professional organizations such as the American Pub- lic Works Association, American Society of Civil Engineers, American Con- gress on Surveying and Mapping, American Society of Photogrammetry, American Bar Association, and American Right of Way Association should jointly develop practical methods for the creation of a utility cadastre.

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