The original coverage was extracted from the USGS 1983 DLGs for the main hawaiian islands.
Description from "Standards for Digital Line Graphs, Part 3 Attribute Coding":
Transmission lines and pipelines are not shown on USGS maps as continuous transportation features. These features are shown more for their landmark character. Pipelines in particular are often shown only where there is a visible scar on the ground. As explained in section 3.0.5, some features are suppressed for legibility concerns. Transmission lines and pipelines are often suppressed for other features, particularly roads. Do not attempt to connect the dropped portions of these features. Digitize these features as shown on the map.
Source: USGS Digital Line Graphs, 1983 version.
Major Codes (1-3): 190 DLG pipes and transmission lines layer
Minor Codes (1-3): Lines: 0201 Pipeline 0202 Power Transmission Line 0203 Telephone Line 0204 Aerial tramway, monorail or ski lift 0205 Arbitrary Line Extension 0206 Closure Line 0207 Aerial Tramway 0208 Monorail 0209 Ski Lift 0299 Processing Line
0400 Power Station or Power Plant 0401 Substation 0402 Hyroelectric Plant 0403 Landing Strip, Runway, Aprox, Taxiway 0404 Helipad 0405 Launch Complex 0406 Pumping Station or Compressor 0407 Seaplane ramp or landing area 0408 Measuring Station or Valve Station 0409 Seaplane ramp 0410 Seaplane landing area
0600 Underground 0601 Under Construction 0602 Abandoned 0603 Aboveground 0604 Labeled "Closed" 0605 Unpaved 0606 Submerged 0607 Nuclear 0000 Photorevised feature