public IReadOnlyDictionary<Element,IReadOnlyList<FieldValue>> AdditionalFieldValues {get;}

public static void GetTraverseAssociationsResultFromUpwardTraversalWithDepthLimit(UtilityNetwork utilityNetwork, IReadOnlyList<Element> startingElements)
{
  // List of fields whose values will be fetched as name-values pairs during association traversal operation
  List<string> additionalFieldsToFetch = new List<string> { "ObjectId", "AssetName", "AssetGroup", "AssetType" };

  // Set downward traversal with maximum depth level of 3 
  TraverseAssociationsDescription traverseAssociationsDescription = new TraverseAssociationsDescription(TraversalDirection.Ascending, 3) 
  { 
    AdditionalFields = additionalFieldsToFetch 
  };

  // Get traverse associations result from the staring element up to depth level 3
  TraverseAssociationsResult traverseAssociationsResult = utilityNetwork.TraverseAssociations(startingElements, traverseAssociationsDescription);

  // List of associations participated in traversal
  IReadOnlyList<Association> associations = traverseAssociationsResult.Associations;

  // KeyValue mapping between involved elements and their field name-values 
  //At 2.x - IReadOnlyDictionary<Element, IReadOnlyList<AssociationElementFieldValue>> associationElementValuePairs = traverseAssociationsResult.AdditionalFieldValues;
  IReadOnlyDictionary<Element, IReadOnlyList<FieldValue>> associationElementValuePairs = 
    traverseAssociationsResult.AdditionalFieldValues;

  foreach (KeyValuePair<Element, IReadOnlyList<FieldValue>> keyValuePair in associationElementValuePairs)
  {
    // Element 
    Element element = keyValuePair.Key;

    // List of field names and their values 
    //At 2.x - IReadOnlyList<AssociationElementFieldValue> elementFieldValues = keyValuePair.Value;
    IReadOnlyList<FieldValue> elementFieldValues = keyValuePair.Value;
  }
}