I was part of a 24-person group who went
to Nebraska at the start of September 2018.
The tour was organised by IrrigationNZ and was an amazing opportunity to
go and see how another part of the world deals with the same issues that we
have here. Below is an overview of my key learnings from the tour.
Governance of Water
The
governance of water in Nebraska is complex. There is Federal legislation, such
as the
Endangered
Species Act, which the state has to abide by. Alongside this there are also
Federal agencies,
such as the Bureau of Reclamation that control most of the surface water
through storage and
diversion infrastructure. The state then sets its own laws around how it will
manage its water.
In Nebraska
the surface water is manged at state level by the Department of Natural Resources,
but groundwater is
managed by Natural
Resource District’s (NRD) at a local level. For a number of surface water
bodies, there are also interstate pacts that determine how much water must
remain in the river to reach downstream states.
The NRD’s
have a Board that is democratically elected, and are often dominated
by rural people
including farmers. Despite this, the farmer representatives have been proactive
in driving practical
change among their peers.
The NRD
system in Nebraska has been very successful in managing groundwater. All takes
are controlled
through a well permit system that allows for a given number of hectares to be
irrigated per well.
Both of the
NRD’s that we visited had invested heavily in science to help them better understand their resource. They also look for solutions as both a farm and catchment level, the latter including
raising capital to build environmental infrastructure such as that required for augmentation projects.
Conjunctive Management
‘Conjunctive
management’ is a recent development in Nebraska that has largely come about through the
management of ground and surface water takes in ‘conjunction’ to achieve
interstate pacts. This has involved the NRD’s (the managers of the groundwater) working closely
with irrigation districts and the Department of Natural Resources to
ensure downstream flows are achieved.
This has
included restriction of individual water takes (wells) – controlling any new
ones, limiting the irrigated
area from existing ones and in some cases placing a seasonal limit on usage.
Alongside the implementation
of environmental infrastructure such as Managed Aquifer Recharge and Stream
Augmentation projects.
Managing Water Quality
Nitrates
in groundwater are of significant concern in the heavily irrigated districts of central Nebraska.
In some areas over 50% of the land is now under irrigated crop-farming.
Historic poor nutrient
management (type and timing) and poor irrigation practice resulted in nitrate concentrations
being frequently observed over 30ppm – well over the US drinking water standard
of 10ppm.
However,
in recent years there has been a significant declining trend, with relatively
few areas now exceeding
20ppm. This has largely been brought about by a non-regulatory approach.
State
law requires the production of water quality and quantity management plans that
identify the issues
and then require the development of an implementation plan to address them. All
the NRD’s have
a rule framework, but most of the rules are currently focused on managing water
takes and farming
practice reporting. Incentives, knowledge and enabling peer to peer learning in
combination with
environmental infrastructure is currently seen as the way forward for water
quality.
The
widespread move from surface flood to centre pivot irrigation has been
instrumental in reducing nitrate
losses to groundwater. This has enabled soils to be irrigated on an ‘as and
when’ basis to minimise
nitrate leaching. There is now also a push towards the more widespread adoption
of fertigation,
as it allows ‘as and when’ nutrient applications – significantly reducing the
risk of leaching
from rainfall events.
Public perception
Despite the
widespread use of intensive farming methods, and the water quality and quantity challenges
facing Nebraska, the one issue currently not facing farmers at the state level
is pressure from the anti-farming lobby or environmental groups.
Of the
almost 2 million people living in Nebraska, the majority understand the role of
crop farming and
ranching in providing for their social-economic well-being. The Nebraskan
economy is based on the
irrigation of almost 4 million hectares of corn and soy beans and this is
widely understood.
The University of Nebraska research and extension service runs an outreach programme
to attract the next generation to agriculture. This currently interacts with one in
every three school age children in the state, providing an agriculture ‘101’
and highlighting
the exciting career opportunities that exist within it.
Keri Johnston, Irricon
Natural Resources Engineer
