Prepared by Tom Mastin PLS

Before we discuss the general process of retracing a simultaneous conveyance, there are some concepts to understand about these conveyances.

• The most common type of simultaneous conveyance is a subdivision, such as a final map or parcel map.
• Because the parcels were all created at the same time there are no senior right issues with Simultaneous conveyances.  
• The rules of retracement must stay within the lots that were created simultaneously.
  • There are many places where subdivisions abut other subdivisions, but each subdivision was not created at the same time only the lots within one subdivision
• Courts strongly believe that a map such as a subdivision map is representing what happened in the field, therefore a discrepancy between what the map shows and what the monuments show in the field would not change the monument locations.
  • Although, these days that does not represent the actual practice, the theory is still valid in that the purchasers can or should be able to clearly see the monuments in the field and therefore believe they are purchasing to those monuments.

Establishment of Interior Boundaries within a subdivision

Excess or deficiencies between accepted monuments or corner locations within a subdivision are distributed proportionally to their record dimensions among all the lots between the accepted monuments. This means that accepted locations must be found on either side of a missing corner, then the distance is measured between the accepted locations and proportioned against the record distance. The arc distance is used along a curve.

Streets are not proportioned in the same way lots are.  If the location of a street can not be determined from monuments (or sometime improvements) and proportionate measure is used across the street, the street will maintain its full width and no more. So when proportioning across a street, the street width is taken out when determining the proportioning factor.

Sometimes, if the original monuments are missing, the subdivision improvements may be used to determine the location of the original lines. This is assuming that the improvements were put in at a time when the original monuments existed and therefore they are a good representation of the location of the lots. A fence built after the monuments have disappeared would not be acceptable to use as an improvement defining a lot line.

It is not uncommon for older subdivisions to have mathematical mistakes in them. The courts put the burden of solving those mistakes on the surveyor. It is your responsibility as a surveyor to do whatever you can to isolate that mistake to where it occurred on the map.

So some basic rules for proportioning are:

• Proportion between the nearest found original or accepted monument locations
• Can not proportion beyond a monument
• When proportioning across a street, the street get its full record width
• Do not proportion across the exterior of a subdivision