ASME-Landmark:Ditch Witch DWP Service-Line Trencher


The Ditch Witch (trencher) Power, or DWP, was the first mechanized, compact service-line trencher developed for laying underground water lines between the street-main and the house. This machine, first produced in 1949, replaced manual digging, thus making installation of running water and indoor plumbing affordable for the common household. The DWP paved the way for the creation of a worldwide trenching-products industry.

To dig narrow trenches, the DWP used a vertical bucket line with an endless conveyor chain to carry off the "spoil." A simple but very unique design, it put the endless conveyor digging chain design concept used on larger ditch digging machines into a small package. Small two-piece buckets with sharp finger-like edges were mounted on a vertical chain to gouge out chunks of dirt. A 6-inch wide trench with a digging depth of 30 inches was the goal.

When he was 27, Ed Malzahn hand-built the first versions in the family machine shop after months of experimentation. Working together, Ed and his father Charlie produced the first production DWP trenchers in 1949. Those were the forerunners of a range of machines that now are known worldwide for durability and reliability in a large array of difficult digging jobs.

In 1955, the U.S. Patent Office issued patent No. 2,714,262 for Ed Malzahn's endless conveyor ditch digging machine. The DWP trencher's compact size and low cost opened the door for making indoor plumbing affordable worldwide. The industry has evolved from the first service-line trencher, the DWP, into today's technologically advanced equipment designed for installation of all underground utilities including telephone, cable TV, and fiber optic communication cables. See ASME website for more information