Water, water everywhere

Flood damage and prevention in Tuscany

Alexandra Korey
February 14, 2013

The unprecedented heavy rains that fell in Tuscany in November 2012 caused almost 50 million euro in damage, leaving families without homes and decimating hundreds of hectares of agricultural land. TF looks at the aftermath of the disaster, and what is being done to prevent further tragedies.

 

Perhaps one of the most defining features of the Maremma is its landscape. The vast area of southwestern Tuscany is predominantly agricultural, except where there are uncultivated hills, woods or beaches. I go there almost every weekend, and feel it is mine in that way that we tend to adopt and feel possessive of places we love. On a recent trip, I noticed deep crevices in the hillside that were not there before. It was like the land had aged and wrinkled overnight. I set out to find out what had caused this damage to la mia Maremma... Maremma, mia!

 

I witnessed this in early December 2012, when I traveled to the town of Manciano for a conference called La Maremma delle Idee, a two-day event presenting ideas on themes of tourism, technology and environment. Manciano is located just inland from Orbetello, and to get there you pass through Albinia, a coastal town that was completely underwater after the heavy rainfall of November 10 to 13, 2012, when the Albegna river overflowed. The main road, its stores and the residential buildings that line it have been power-washed clean. On the surface, the town does not look that different than it did the month before.

 

However, it is when you get out of Albinia and see the previously fertile farmlands and hillsides that you realize something has profoundly changed. A pile of mud-covered, discarded pieces of furniture, appliances and personal belongings outside of a farmhouse betrays the personal tragedy of its dwellers; a field whose land is so impregnated with water that it seems it will never dry out; a car moored somewhere in its midst; and hills with these crevices, half a meter wide, 25cm deep, that can't possibly be anything good.

 

At the conference in Manciano, an agronomist named Roberto Barocci spoke about this very issue. The crevices are called rills and they are a kind of extreme soil erosion that formed because of the exceptional amount of rain that fell; since it had no other paths to follow, it headed straight down the hill. The water cuts through the topsoil, bringing an incalculable quantity of earth with it; this mix flows down to the riverbank, raising its levels and contributing to its inability to contain water. Where you see these rills, there is no organic substance left. This is dead land.

 

While I witnessed this phenomenon in the province of Grosseto, this winter's rains have caused the same problem in neighbouring areas, too. Barocci maintains that two things could have been done to avoid it. First, the evolution of agriculture in the past few decades has seen fewer animals at pasture, which naturally enriches the soil with humus, a substance that absorbs 20 times its own weight in water and minerals. Humus-rich soil holds water and earth on a hill better than soil weakened by modern farming practices. A return to the use of humus is something that can be done on a local level without particular investment.

 

The second prevention factor is much more difficult to implement: a law passed in 1989 (specifically, Legge 18 Maggio 1989, n. 183: Norme per il riassetto organizzativo e funzionale della difesa del suolo) sets a series of hydraulic planning guidelines that suggest the creation of detention basins in areas with rivers at risk of flooding. These are essentially floodable fields to which water is diverted in case of imminent overflow. Despite this being one of the best known, most sustainable solutions in flood prevention, few basins have actually been built in Italy, though information dating back to 2009, available on the Tuscan Region's website, indicates that 168 such projects are underway.

 

On January 17, 2013, Tuscany signed an agreement with the national government that will provide co-financing for a pilot program in hydraulic risk prevention to the tune of 600 million euro. This amount comes in addition to the funds allocated in November 2012 for the emergency clean-up effort (14 million euro) and urgent maintenance (100 million euro) interventions. The work to be done ranges from cleaning up riverbanks to securing bridges (a more specific list is not publicly available at the moment).

 

The infographic below helps understand the magnitude of flooding and its economic consequences:

Flooding in Tuscany infographic

 

But, will this investment keep us safe from future flooding? I asked Andrea Giacomelli, an engineer with a PhD in hydrology who now works as an environmental awareness activist, what we could do to avoid disasters. He says ‘not much,' as long as we blindly rely on data and predictions. He then showed me something called an intensity-duration frequency curve, a statistical tool that determines the size of a ‘rainfall event' (or simply put, how much it rains in one storm) that statistically occurs every 10, 20, 50 or 200 years. These curves are used when calculating things like the height of a levee or the capacity of storm sewers, which are made to resist reasonable recurrences. Sometimes, you get an unpredictable amount of rain, which is what happened last November. It rained 170 percent more than the 200-year return period (or record rainfall) in the Grosseto region. At these levels, there is almost nothing you can do except pull out your wellies.

 

But Giacomelli is a believer in mixing scientific data with human knowledge. If called in to consult in an area, he speaks with local farmers, the people who have closest contact with the land, because from them he can gather the kind of intimate, non data-based knowledge that is accumulated over generations of experience. On the other hand, sometimes large government-sponsored projects are carried out in contrast with local logic. An example is the re-planing of a riverbank of the Albegna, not far from Manciano. Local journalist and activist Andrea Marciani published an article in March 2012 (http://tinyurl.com/c7ekhhk), which points out that this ‘maintenance work' ripped out trees, roots and other vegetation essential to keeping water in its place. As one reader commented: ‘Even rocks know that trees and vegetation are a natural barrier to erosion and the flow of water!' Unfortunately, the recent river clean-up was just upstream from a bridge that tragically collapsed in the November floods, taking the lives of three people.

 

The problem is, of course, a very big one, and most solutions are out of our reach as common citizens. Unusual natural events combined with modern migration towards cities-a phenomenon more recent in Maremma than in other places-has caused a lack of connection to the land.

 

Giacomelli's organization, Pibinko.org, holds music and environmental events in the area, hoping that the presence of entertainment and communication outlets might encourage people to stay, or to move back as he has. ‘Solutions will be found with those who live in the territory, working with them to find out their priorities and expectations, and using their local knowledge,' he says. Local knowledge that needs to be combined with global priorities and scientific understanding in an attempt to limit damage caused by inevitable elements.

 

Feeling small and insignificant in the face of these problems that are damaging ‘my Maremma,' I asked Giacomelli if there was anything that we, common citizens, could do. He told me three little things anyone can do to raise their personal level of awareness about hydraulic risk issues and safety (see graphic below).

 

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