Water conservation and water saving

The terms water conservation and water savings are generally associated with the management of water resources under scarcity. However, these terms are often used with different meanings in accordance with the scientific and technical disciplines or the water user sector considered. Very often, both terms are used as synonymous.

The term water conservation is used when referring to every policy, managerial measure, or user practice that aims at conserving or preserving the water resources, as well as combating the degradation of the water resource, including its quality. Water saving aims at limiting or controlling the water demand and use for any specific purpose, including the avoidance of water wastes and the misuse of water. In practice both perspectives are complementary and inter-related. Despite not being easy to distinguish between them, these terms are not used synonymously. In particular, questions relative to preservation and upgrading of water quality are considered as water conservation.

In other sections of this chapter, like in other chapters of this book, different facets of water conservation and water savings are analysed, described and proposed for adoption.

Thus, it looks appropriate to first review some of most important aspects of those measures and practices used to cope with water scarcity. These measures and practices are summarised in Tables 8.1 and 8.2 for water conservation and water savings respectively. The tables refer to their relative importance for coping with the water scarcity regimes identified in Chapter 2.

In the following sections those measures and practices which have much in common concerning their application to those water scarcity regimes are analysed, focusing on the peculiarities of each one of them.

This chapter analyses with some detail the measures and practices that can be applied by the different user sectors - urban systems, domestic water uses, landscape and recreational uses, industrial and energy, and agriculture, both dryland and irrigated agriculture - to reduce both the water demand and the water consumption, as well as to improve the efficiency in the use of water. These measures and practices constitute guidelines for establishing local, regional or national programmes for water conservation and saving in the different water use

T^ABLE 8.1. Water conservation measures and practices and their relative importance to cope with different water scarcity regimes

Water conservation measures and practices Aridity Drought

Desertification and water shortages (a) Meteorological and hydrological information networks to

support planning and real time operation and management of reservoirs and water supply and irrigation systems

H H (drought

watch systems)

H

(b) Storage and regulation reservoirs for improved availability of

the water resources H H M

(c) Land and water use planning and management H L H

(d) Enforcing water quality management measures and practices, H/M L H (e) Improved conditions for operation, maintenance, and

management of water supply systems, H/M H M

(f) Maintenance of required discharges for ecological purposes

in natural streams and water bodies H L H

(g) Controlling ground-water withdrawals, recharge and

contamination H/M L H

(h) Enforcement of water allocation policies focusing on the

prevalent water scarcity problems H H H

(i) Augmentation of available water resources through the re-use of treated waste-waters, drainage and low quality waters, for specified uses

H H M/L

(j) Exploring non-conventional water sources by households,

farmers, industry and water supply bodies H/M H L

(k) Adoption of water technologies and practices by the end

users for resource conservation H H H

(l) Development of soil and water conservation practices in

rainfed and irrigated agriculture H H H

(m) Erosion control and soil conservation, M L H

(n) Development of soil and crop management practices for

restoring the soil quality, M L H

(o) Combating soil and water salinisation H L H

(p) Development of participative institutions to water management, including legal and regulatory measures

H H H

(q) Application of water pricing and financial incentives that favour efficient water uses, and treatment, re-use and recycling of the water,

H H H

(r) Adoption of penalties for water wasting and misuse, and

degradation of the resource H H H

(s) Enhancing public awareness of the economic, social and

environmental value of water, including nature conservation H H H H = high to very high importance; M = important but not having first priority; L = important but having low priority

T^ABLE 8.2. Water saving measures and practices and their relative importance to cope with different water scarcity regimes

Water saving measures and practices Aridity Drought

Desertification and water

shortage

(a) Control of evaporation losses from reservoirs, H/M H L

(b) Control of leaks from canals and conduits, H/M H L

(c) Control of spills from canals and other hydraulic

infrastructures, H/M H L

(d) Exploring information systems for decision makers, water

system management and improved water uses , H H (drought

watch systems)

H

(e) Implementing reservoir and ground-water management rules, H H H (f) Enforcing water scarcity oriented water allocation and

delivery policies H H H

(g) Adoption of reduced demand crops, cropping patterns,

cultivation practices, and irrigation techniques, H H (drought tolerant crop

patterns)

H

(h) Cropping and irrigation practices oriented to control non-point source pollution by agro-chemicals, fertilisers and erosion sediments

M L H

(i) Adoption of deficit irrigation practices M H M

(j) Adoption of irrigation and drainage practices favouring

salinity management M L H

(k) Adoption of farm water storage and soil water conservation practices

H/M H H/M

(l) Use of inferior quality water for irrigation H/M H L/M

(m) Water recycling in industry and in energy generation H H L/M

(n) Adopting water saving tools and practices for reducing domestic, urban, and recreational water uses

H/M H L/M

(o) Water price policies in relation to the used water volumes,

the specific uses, and the productivity of water use, H H H

(p) Incentives for reducing water demand and consumption H L/M H

(q) Penalties for excessive water uses as well as for low quality

effluents and return flows, and H H H

(r) Education and campaigns for adoption by end-users of water

saving tools and practices. H H H

H = high to very high importance; M = important but not having first priority; L = important but having low priority

sectors, focusing on the aspects and issues that are more relevant to the areas under consideration. An example of potential application of these guidelines is the program for efficient water use developed for Portugal (LNEC/ISA, 2001), which was developed in parallel to this chapter and followed the approach described here but focusing on the problems and issues more relevant to that country.