Walker - 1967 - A geography of Italy

ITALY IN THE NINETEENTH CENTURY
through the barrier which prevented direct access to the main drains. Even now
much remains to be done. The other difficult areas in Tuscany lay in the middle
and lower Arno valley where the Fucecchio district and the Bonifica^ di Coltano
(between Pisa and Leghorn) had raised many false hopes; the former was finally
tamed in the ‘eighties’ and the latter only in 1920.
In the Po Valley lay the greatest hydraulic problem in Italy, and also the
greatest opportunity. The annual load o f the river near its mouth has been
estimated at 40 million tons, and the annual advance o f the delta at between
30 and 80m. The raising o f the bed between levees, severe floods, and shrinkage
where poldering had been attempted, had hindered reclamation in the very low
areas, but with the application o f new techniques successful drainage was now
possible. In the ‘eighties’ the work was began on the Bonifica Ferrarese, between,
the Po Grande and the Po di Volano, the Bonifica di Burano west o f the Panaro’s
junction with the Po, and the Bonifica Parmigiano-Moglia lying between the
Secchia, Crostolo and Po rivers. This work which involves hundreds o f thousands
of acres has continued to the present. From the very nature o f the area holdings
are extremely large and heavily capitalized. In the lower Reno area the colmate
method has been applied successfully.
Two other reclamation areas deserve special mention, the Fucino Lake, and
the Pontine Marshes. The Romans had achieved some success with L. Fucino,
but the conduits to the Liri had soon become blocked and attempts to free them
in the Middle Ages were fruitless. The lake level had always been subject to
fluctuations because o f connections with the underground drainage o f the
surrounding limestone, but in 1852 it rose alarmingly to 9m above normal. Tw o
years later Prince Alessandro Torlonia engaged the Swiss engineer Montricher
to drain the lake to the Liri and reclaim the area for tillage. The project, completed
in 1875, was remarkably successful, and an area o f 15,500 hectares was
drained and divided into tenant farms o f varying sizes, organized and financed
by the Torlonia estates. The Pontine Marshes presented a tougher problem. The
area lies between the Lepini and Ausoni Mountains and the coast from M.
Circeo to a point a mile or two south o f Anzio. This covers 80,000 hectares, o f
which 50,000 were pestilential fen, and 30,000 consisted o f Quaternary spits and
dunes along the coast, largely covered with macchia. It was this low ridge which
barred the path o f the mountain streams and turned such drainage as existed
south-eastwards. The short streams issuing from the limestone hills had insufficient
load to furnish colmate and almost all the schemes had as their basis
the improvement o f the drainage south-eastwards by main canals and feeders.
Such was the Rio Sisto constructed by Sixtus V (c. 1590) along the eastern
margin o f the dimes and the ambitious Linea Pia built by Pius V I (c. 1777),
which followed the line o f the Via Appia and received feeders from the east at
mile intervals to take the surplus mountain water. Although the work continued
spasmodically throughout the nineteenth century descriptions o f the area at the
* Bonifica means any area improved by man.
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