When It Comes To Water, Weather Matters.

Posted on | July 16, 2023 | Comments Off on When It Comes To Water, Weather Matters.

Mike Magee

We forget that the water cycle and the life cycle are one.
— Jacques Cousteau

When the Simon Pearce restaurant and glass blowing studio flooded on the banks of the Quiche Dam in Vermont during Tropical Storm Irene in 2011, it was supposed to be the result of a once in a century event. But this past week, it happened again. Welcome to New England 2023 – and multiple locations around the globe – where atmospheric rivers, and massive epic cloudbursts, have revealed not simply the effects of human induced global warming, but historic underinvestments in water infrastructure and Integrated Water Resource Management (IWRM).

Global management of water resources was first discussed at a global water summit organized by the UN in Mar del Plata, Argentina, in 1977. By 1992, water was a central theme at the World Summit of Sustainability Development in Rio. By 2009, all nations agreed on a definition for Integrated Water Resource Management (IWRM): “IWRM is a process which promotes the co-ordinated development and management of water, land and related resources, in order to maximize the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems.”

The hydrological cycle itself, throughout human history, has been dynamic. It is now generally accepted that the assessments of the Intergovernmental Panel on Climate Change have accurately identified that global temperatures will rise 1.5 C above pre-industrial levels by 2030 largely as a result of the emission of greenhouse gases especially carbon dioxide (CO₂). In response, ocean levels are rising, more energy exists in the climate system, and the global hydrological cycle is intensifying. How will this be expressed? We have already seen changes in amount and intensity of precipitation, in seasonal distribution, and in frequency. These events in turn will lead to changes in magnitude and timing of water runoff, intensity of floods and droughts, regional water supply levels, levels of surface and ground water. In short, “terrestrial components of the hydrological cycle amplify climate input.” Translation, when it comes to water, weather matters.

Precipitation across the globe is highly variable from highs of 2400 millimeters per year in the tropics to lows of 200 millimeters or less in the subtropics. Soil is a significant reservoir for water. Amounts are not only driven by the rates of precipitation and evaporation, but also by soil type and depth, vegetation, topography, and seasonality. The top two meters contain the majority of the moisture. Significant water also collects in subterranean spaces. Groundwater is the predominant strategic reservoir on Earth, some 30% of the global fresh water total and 98% of the drinkable and potential accessible supply. Critical to human development and in the past 50 years, with advances in drilling and pump technology, groundwater has rapidly become the worlds “most extracted raw material”. And compared to surface water, there is very little loss to direct evaporation.

The challenge remains how best to scientifically manage this raw material to assure long term, sustained development. This requires a better understanding of how the ground water systems function, their recharge processes and their relationships to surface water bodies. It also means managing and protecting the purity and integrity of the resource, a knowledge of the geology, better monitoring of groundwater levels, and real-time data of depth, flows, and extraction levels.

As water seeps into groundwater aquifers it also seeps out through watercourses, wetlands and coastal zones. Recharge rates are highly variable and affected by changes in surface vegetation, surface water diversion, changing water table levels, and climate cycles. Sustainability issues include inefficient use, social inequity, unsustainable extraction, icy weather reductions, aquifer damage, land compaction, and ecosystem damage. All of the above are under human control. Aquifers are far more resistant to contamination than are surface water bodies. But once contaminated, aquifer damage is difficult to reverse.

As with most enlightened policy, good planning and prevention pays off. Sound system design, proper land use rights, ongoing investment in technology, stakeholder participation, and careful monitoring, design and operation are critical. But what’s unique about water is that water flows. And in flowing, it crosses multiple jurisdictional borders. So proper management and planning require intergovernmental cooperation.

The human touch has left its mark. From industrial heavy metals to acid rain, from leaking storage tanks, accidental spillage, and domestic sewage, to municipal waste and agro-industrial effluent, people and water definitely do mix. Besides affecting the quality of drinking water, secondary impacts have become common. For example, the discharge of organic material, high in nitrogen and phosphorous, into surface water fosters abnormal and explosive plant growth depleting oxygen and affecting the entire ecosystem and the life forms it supports. Twentieth century ecosystem degradation has resulted in the loss of 2/3rds of our wetlands profoundly impacting fresh water species.

Water on the move cannot be separated from solid and particulate sediment. Much exists as suspended matter, actively in motion. In fact, more than 50 billion tons of suspended sediment are carried by river waters to the oceans each year. What lands in surface water and ground water bodies is increasingly a function of human action and planning. For example, creation of solid surfaces (contributing for example to the 500-year flood in Houston, TX in 2017) increases volume and rate of runoff, downstream flooding, and human chemical deposits into surface water. Over-mining of ground water impacts water levels and the capacity to live off the land in stressed locations around the world. High surface runoff carries with it expanded sewage runoff in urban environments. Poor liquid waste disposal and hazardous chemical spills travel rapidly above the ground and easily penetrate below the ground in many locations. And as these collective actions impact lakes, rivers and streams, habitats and species diversity declines.

There is then a natural, interconnected, and crucial water cycle upon which all life on earth depends. Humans have always required a dependable water supply to survive and thrive. As we have grown in numbers and in concentration; as we have built and infiltrated among, and at times, in opposition to other life forms, we have created future health challenges that must now be addressed. Global warming is an accelerant. The time for each of us to better understand the nature of water, and its relations to weather, ecosystems, agriculture, industry, urban planning, sanitary systems, and value of Integrated Water Resource Management (IWRM) is long overdue.