Blue Territory

Water management is not only about homes and cities. Agricultural and peri-urban areas can also make a crucial contribution to the local water balance.

A Blue Territory slows water down, retains it when it is abundant, makes it available during dry periods and, where possible, supports groundwater recharge. Fields, ditches, hedgerows, tree rows, woodlands, healthy soils and small retention basins can form a distributed network of solutions for better water management.

Soil as water infrastructure

Healthy soil is not merely the physical foundation for crops. It is a living system made up of minerals, roots, microorganisms, organic matter, pores and water.

Soil rich in organic matter retains more water, promotes infiltration, reduces runoff and erosion, supports fertility and makes crops more resilient to environmental stresses.

FAO and USDA-NRCS highlight the role of cover crops and organic ground cover in protecting soil, increasing organic matter, improving soil structure and promoting water infiltration.

Useful agricultural practices

In agricultural and peri-urban areas, the most useful practices include cover crops, green manures, organic soil amendments, regenerative agriculture, buffer strips, hedgerows and tree rows, bioretention ditches, small-scale field water retention measures, farm ponds, controlled recharge areas and efficient irrigation.

Reducing deep tillage, maintaining soil cover during otherwise bare periods, crop rotation, incorporating crop residues and reducing soil compaction all help the soil retain water and better withstand extreme events.

In many situations, an increase in soil organic matter can be used as a useful indicator for assessing improvements in the soil’s water retention capacity. However, quantitative targets should be defined on a case-by-case basis, according to crops, soil characteristics, agricultural practices and available analytical data.

Buffer strips, hedgerows and tree rows

Vegetated buffer strips between fields and ditches intercept sediments, nutrients and some of the pollutants carried by runoff. They slow surface water flow, protect ditches and watercourses, and enhance biodiversity.

Hedgerows and tree rows provide additional benefits: they offer shade, reduce wind exposure, improve the local microclimate, provide habitats for beneficial wildlife and create ecological corridors. In intensively farmed areas, they act as small-scale green infrastructure with significant ecological and hydrological value.

Ditches, drainage and small-scale water retention

Ditches and drainage channels should not be considered merely as drainage systems. They can also be managed to slow down water flows, retain sediments and improve runoff quality.

Possible solutions include vegetated ditches, two-stage channels, small channel widenings, bioretention areas, temporary wetlands and differentiated vegetation management.

Small-scale field water retention measures are distributed systems designed to temporarily hold water. Furrows, field bunds, shallow depressions and other land management features can slow runoff and retain water from more frequent rainfall events.

Water storage, groundwater recharge and efficient irrigation

Small farm reservoirs and water retention areas can store water during wet periods and make it available for later use, provided that water quality, authorisation requirements and site characteristics are taken into account.

In suitable areas, water can be directed into the subsurface through managed aquifer recharge systems. This does not mean simply allowing water to infiltrate without proper assessment: geological, hydraulic and water quality evaluations are essential.

Saving water in agriculture does not mean simply irrigating less, but irrigating more efficiently. Soil moisture sensors, weather data, water balance assessments, drip irrigation, irrigation scheduling at appropriate times, mulching and the selection of suitable crops are complementary tools for improving water efficiency.

Water quality and maintenance

Retaining and infiltrating water is beneficial only when the water is compatible with the protection of soil and groundwater. Where nutrients, pesticides, contaminants or inadequately controlled discharges are present, filters, buffer strips, treatment systems or other solutions are needed to prevent direct infiltration.

Maintenance is an integral part of the design: ditches, reservoirs, filters, vegetated areas and irrigation systems must be monitored and maintained over time. A nature-based solution is not a maintenance-free solution.

Best practices:

· Italy - Bosco Limite, Carmignano di Brenta: an agricultural area transformed into a multifunctional forest that supports groundwater recharge, biodiversity and ecosystem services. It provides a reference model for forested infiltration areas and integrated water and nature management. 

· Italy - LIFE AQUOR, upper Vicenza plain: it demonstrated a participatory model for restoring the quantitative balance of groundwater resources through water conservation and managed aquifer recharge in the Upper Vicenza Plain.

· Italy - LIFE BEWARE, Upper Vicenza Area: it tested natural water retention measures in urban and rural areas, linking climate adaptation, flood risk management, training and community participation. 

· Europe - Room for the River, The Netherlands: The Dutch programme created more space for rivers to reduce flood risk, while also enhancing the landscape and ecological quality of river areas. 

· World - USDA-NRCS: good practices for soil health: U.S. soil health guidelines promote cover crops, living roots, reduced tillage and increased soil organic matter as practices that also support water infiltration and conservation.