152 GUIDEBOOK OF THE WESTERN UNITED STATES. 
South of De Beque the railroad is built on a low terrace at some 
distance from the river, but near the entrance to Palisade Canyon, 
44 miles south of De Beque, halfway between mileposts 48 and 49, it 
reaches the river (on the left) in a shallow canyon cut into one of 
the thick beds of sandstone near the top of the coal-bearing Mesa- 
verde formation. As the beds rise gradually downstream the canyon 
slowly increases in depth from its head to Palisade, where it ends. 
At Akin siding (milepost 51) the canyon walls are about 300 feet 
high, and they show well the alternate bands of resistant sandstone 
and soft, easily eroded shale. Here and there some of the beds of 
sandstone are thick and massive and form cliffs 40 or 50 feet high, 
but. on the whole the alternation of shale and sandstone gives rise 
to sloping banded walls which have a sameness in appearance that 
soon becomes monotonous. 
At Tunnel siding (milepost 55) the walls of the canyon have in- 
creased in height to 600 or 700 feet, but they have the same general 
character. A mile west of this siding the train passes through a 
tunnel which pierces a long spur (shaped in plan like a beaver’s tail, 
hence the name Beavertail tunnel) that projects from the right 
wall of the canyon and then comes to a diversion dam which turns 
some of the water of Colorado River into a canal on the other 
side of the river. This canal is in sight throughout the length of 
the canyon below this point, and its effects may be noted in the 
crops and orchards on the high bench lands east of the river. 
Milepost 57 marks the largest diversion project in the canyon, 
known as the Grand Valley or High Line project of the United 
States Reclamation Service, which is intended to furnish water 
for the irrigation of the high bench lands on the north side of the 
river from Palisade as far west as the western boundary of the 
State. The diversion dam, shown in Plate LXVI, is completed, and 
the canal is constructed as far west as Loma (see p. 153) and in the 
near future will be extended to the State line.*? 
“The Grand Valley project of the ; tending to a point 6 miles northwest 
United States Reclamation Service, | of Mack. 
usually spoken of as the High Line 
eanal, provides for the irrigation of 
45,000 acres of land in M County, 
Colo., comprising, as shown in figure 
39, a strip along the northern border 
of the valley above the old private 
canals from 2 to 6 miles wide and 40 
miles long. The water is taken from 
Colorado River (formerly called Grand 
River) by a diversion dam (shown in 
Pl. LXVI) 8 miles above Palisade, into 
a main canal 65 miles in length, ex- 
plied by gravity, and 10,000 acres lies ~ 
above the level of the main canal and 
will be supplied by electrically oper- 
ated pumping plants. 
e most interesting engineering 
works in this project are the diversion 
dam and the first 6 miles of main 
canal, which are in the canyon of 
Colorado River. The dam, which is 
unique in American engineering, CoD 
sists of a concrete weir, 546.5 feet im 
phe Se 3k 
