**1. Introduction**

Eutrophication of inland water is a prevalent issue in Malaysia, one which threatens the functioning of lake and reservoir ecosystems throughout the country. A preliminary study of the status of lake eutrophication reported that more than 60% of the 90 lakes being studied

© 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

were nutrient rich [1] with a few of them especially the urban lakes experiencing algal blooms, which affect human uses of the water, such as recreation and aesthetic values, while other lakes faced macrophyte infestation problems [2]. To address these widespread challenges, develop‐ ing specific standards for lakes is necessary before introducing a monitoring programme and identifying management measures for improving lake water quality. At present, there are only two national standards of water quality in Malaysia, namely the National Water Quality Standards (NWQS) and the National Drinking Water Quality Standards (NDWQS), which were developed for the purpose of river and drinking water protection. Currently, lake monitoring efforts have focused on using the NWQS due to the unavailability of specific water quality criteria for lakes. In an earlier work, it has been shown that the majority of the lakes studied were categorized as suitable for recreational purposes, although, they did experience eutrophication [2].

Numerous ambient water quality criteria and standards have been introduced and published in various countries throughout the world [3] and compiled based on different uses [4]. Many of these criteria were developed for different protection objectives, mostly for drinking and/or recreation, and derived using different methodologies. Some countries propose unified regulatory standards that classify all water bodies based on beneficial uses [5]. Other countries use general standards which are applied to the water bodies for multiple purposes, with different numerical limits set for different types of water bodies, such as rivers, canals, lakes and coastal waters [6]. In some countries, such as Japan, a specific law to preserve lake water quality, better known as the Clean Lake Law, has been established to protect and improve water quality in the water bodies. Individualized measures have had to be developed in Japan due to differing water quality conditions, sources and causes of pollution amongst lakes [7]. In many states in the United States, site‐specific criteria incorporating lake basin features and maximum load have been proposed, such as in the cases of Lake Erie and Lake Tahoe [8, 9]. As national standards for river and marine waters are available, specific criteria and standards for lakes are also needed so that Malaysia can ensure the sustainable management and protection of this lentic water due to its inherent characteristics.

This work describes the efforts in developing a National Lake Water Quality Criteria and Standards (NLWQCS) for Malaysia. The paper will be presented in three ways: (i) a review of the lake water quality criteria and standards in existing literature; (ii) classification and criteria, based on multi‐stakeholder consultations and published data and (iii) discussion of the role of this standard for lake management. The main objective in developing these criteria is to provide a standardized reference for the monitoring and management of lakes, based on a consensus of local experts and stakeholders, namely the lake managers and lake owners such the state authority, state water authority and government agencies.
