public bool AddAssociatedLayers {get; set;}

{
    var path = @"D:\Data\CommunitySamplesData\Topology\GrandTeton.gdb\BackCountry\Backcountry_Topology";
    var lcp = new TopologyLayerCreationParams(new Uri(path));
    lcp.Name = "GrandTeton_Backcountry";
    lcp.AddAssociatedLayers = true;
    //Note: Needs QueuedTask to run
    var topoLayer = LayerFactory.Instance.CreateLayer<ArcGIS.Desktop.Mapping.TopologyLayer>(lcp, MapView.Active.Map);
}

{
    //Get the Topology of another Topology layer
    var existingTopology = MapView.Active.Map.GetLayersAsFlattenedList().OfType<TopologyLayer>().FirstOrDefault();
    if (existingTopology != null)
    {
        var topology = existingTopology.GetTopology();
        //Configure the settings for a new Catalog layer using the CatalogDataset of an existing layer
        var topologyLyrParams = new TopologyLayerCreationParams(topology);
        topologyLyrParams.Name = "NewTopologyLayerFromAnotherTopologyLayer";
        topologyLyrParams.AddAssociatedLayers = true;
        //Note: Needs QueuedTask to run
        LayerFactory.Instance.CreateLayer<TopologyLayer>(topologyLyrParams, MapView.Active.Map);
    }
}