24 / 36
20
DELTARES, September 2016
During the 2003 World Swimming
Championships in Barcelona, Hans Hill
was sitting on the couch watching an
interview with swimmer Inge de Bruijn,
who said that she couldn't break her
world record because of her own bow
wave at the turns. Hans, who was still
working as a commercial photographer
at the time, was intrigued: ‘I thought:
that's odd, there has to be a way around
that.’
Kitchen sink
The inventor walks to a cupboard full
of home-made models of plaster,
styrofoam and plastic. ‘At the time in
Barcelona, they were
using a new type
of lane line but the
blocks on the lines
were way too close
together. The waves
couldn't penetrate
into the small gaps
and break the bow
wave. The blocks should take up the
water from the wave and then release it
back into the pool slowly.’
Don't you have to be an engineer for
ideas like this? Not necessarily, says
Hans. ‘As a photographer, I look at
details, pick up inspiration from the
world around me, and draw on my past
experience. Knowledge can also be a
negative factor: it stops you thinking in
simple ways.’
He started working on a design and
tested all his prototypes at home in the
kitchen sink. A pillar-shaped piece of
styrofoamwith holes was the result.
He was convinced it would work but
the Swedish company that makes pool
equipment wasn't interested. Hans Hill
was not about to give up: the Technical
University in Delft, Rijkswaterstaat and
MARIN in Wageningen were next on his
list.
Frompool to dike
‘My contact at Delft University of Tech-
nology said that my idea could be use-
ful for dikes because dike revetments
also absorb waves.’ He plunges back
into the cupboard and emerges with
two small plaster models: the primi-
tive versions of the Hill Block. ‘I came
up with these. They were still hard to
make: the upper part had to be glued on
separately. But they worked.’
Initially, Rijkswaterstaat and Delft Uni-
versity of Technology were sceptical: ‘I
hadn’t studied at a technical university.
They told me that a lot of researchers
had already tried to optimise revetment
blocks. “The gaps between the blocks
are too large,” they said. They thought
A swimmer gave former commercial photographer
Hans Hill the idea for a new type of float on lane lines
in swimming pools. It was the first step on the road to
a revolutionary type of block for dike revetments. Hill
Blocks are now used on about 16 kilometres of dike in
the Netherlands. An interview with the inventor about
the value of good research.
BY ANNEMIEK MEERTENS
IMAGE SAM RENTMEESTER
FROM KITCHEN
SINK TO DELTA
FLUME