https://e360.yale.edu/features/green-roads
"Makueni County, a corner of southern Kenya that’s home to nearly a million
people, is a land of extremes. Nine months a year, Makueni is a hardened,
sun-scorched place where crops struggle and plumes of orange dust billow from
dirt roads. Twice yearly, though, the county is battered by weeks of torrential
rain, which drown farm fields and transform roads into impassable morasses.
“Water,” says Michael Maluki, a Makueni County engineer, “is the enemy of
roads.”
Maluki’s axiom is true the world over: Where roads and water intersect, trouble
follows. Roads cut off streams and bleed sediment; meanwhile, floods often
erode roadbeds into muddy gullies. Although wealthy nations are far from
immune, these problems are most severe in developing countries, where roads are
largely unpaved and thus especially vulnerable to obliteration. In Kenya and
other nations, the issue is exacerbated by climate change, which has amplified
the intensity of seasonal monsoons and droughts.
In 2019, Maluki began to ponder how to reconcile two of his county’s
challenges: the aridity of its dry season and the destructiveness of its wet
season. That year, he and colleagues attended a local workshop led by a Dutch
consulting firm called MetaMeta on the concept of “Green Roads for Water” — a
set of precepts for designing roads to capture water through strategic
channels, culverts, and ponds and divert it for agricultural use. Inspired by
the session, Maluki brought the idea to his colleagues and local farmers, who
gave Green Roads their cautious blessing.
Makueni County’s Green Roads quickly proved their worth. Along roadsides,
Maluki’s team members installed “mitre drains,” which shunted floodwaters into
newly dug channels that irrigated mangoes, bananas, and oranges. They excavated
farm ponds, which stored the rainy season’s floodwaters for use during drought,
and they planted roadside fruit trees to absorb runoff and help control the
dust that billowed from unpaved roads. And where travel routes crossed
ephemeral rivers at right angles, the county built drifts — concrete road
segments that also functioned as makeshift dams. During seasonal floods, the
drifts captured deep banks of sand on their upstream sides. The sand retained
pockets of water, which farmers tapped during the dry season via four-foot-deep
wells dug upstream of the drift. In neighboring Kitui County, one study found
that every $400 spent on similar low-tech tweaks increased farmers’ yields by
around $1,000; according to Maluki, they’ve also made the rainy season far less
damaging.
“The biggest asset for [the county government] in this program is the reduction
of maintenance costs,” Maluki says. “It’s a two-way benefit.” He estimates that
between 5 and 10 percent of the counties’ roads now apply water-harvesting
principles."
Via
Fix the News:
<
https://fixthenews.com/good-news-human-rights-greece-education-burundi-reforestation-america/>
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
