The Mala Dam Circle is a good 4 hours and there is quite “a lot of up” as my walking companion put it and she is not wrong. The effort is well rewarded however with stunning views and a definite sense of achievement at the end.
Not recommended for hire cars, but there is a dirt road that runs up to the top of the dam wall (C. Pleamar). This is where I parked and we were most grateful to save a few thousand steps at the end of the walk.
The walk takes you up onto the ridgeway with great views down into the two valleys. On the left-hand side facing west you have Baranco Valle del Palomo. On the right-hand side facing west you have the Tabayesco valley. The route emerges briefly onto the LZ-10 before beginning its descent down C. Pleamar back to the Dam.
Water Secrets
At the top of the climb from the dam you can look down onto La Fuente De Chafariz. As you circle back down the dirt track C. Pleamar you find an old spring which you can imagine as being opposite the upper water extraction tunnels of La Fuente De Chafariz.

Spring just off C. Pleamar, Baranco Valle del Palomo. Appears to opposite side of the mountain to La Fuente De Chafariz.
Disused water extraction tunnel above La Fuente De Chafariz in Barranco del Chafariz above Tabayesco.

Mala Dam Circle- History
To read more on the history of water on Lanzarote you can checkout the following sites:
These sites are in Spanish, so if it helps I have made an attempt to cover some topics of interest in the History section.