Limitations in Tax Mapping
Despite this, tax maps have taken on many unofficial uses and can often be seen in use by governments for county and local planning, determination of special district boundaries, recording sewer, water and drainage information and selecting routes for highways, sewers and other municipal improvements. Many modern Geographic Information Systems (GIS) and maps will utilize parcel boundaries taken from the tax map to provide representations of land ownership in a community. The tax map number, or section, block and lot (SBL), is utilized on the assessment roll and is recorded on the cover sheet for all deed conveyances in the County Clerk's office.
It must be understood that the tax map does not constitute a claim of right by the owner of real property, except in the case where the owner holds a tax title. The public record and an accurate field survey are much better evidence in determining title than is the tax map. Given the length of time allowed for the creation of tax maps, it is remarkable that they are of such high quality, but for even the most simple survey a land surveyor will have spent more time on that parcel than the tax mappers spent on the most difficult parcel on the tax map.