Lake Conservation Measures of

December 11, 2019

HASHIMOTO Tsubasa Deputy Director, Water Environment Division, Environment Management Bureau, Ministry of the Environment, Japan

1 Current state of water quality and pending issues in Japan

Wastewater regulation, better sewerage, and other measures have, to some extent, reduced the inflow load of nitrogen and phosphorus and improved water quality in , but there is need for further improvement because it has been harder to meet environmental standards in lakes than in rivers.

ＮＯｘ Naturally derived nitrogen Precipitation, etc. and phosphorus

Reduced fertilizer Chemical use policies fertilizers & feed Waste treatment Domestic Place-of-business wastewater wastewater Wastewater regulation Groundwater infiltration Sewage treatment Nitrate nitrogen Domestic Food & raw Accumulation, nutrient build-up wastewater materials Urban effluent Removal of nutrient salts from Road cleaning circulation by mowing and fishing, etc. Lake bed accumulation & elution into lake water

Algal blooms, putrefaction odors, damage to water quality and poor bottom layer oxygenation Ministry of the Environment 2 Trends in meeting environmental standards (BOD/COD)

♦ Among standards for protecting the living environment of the people, organic pollution standards (BOD and COD), overall, have gradually tended to be better met. ♦ While standards in rivers are now generally met, in lakes, bays, inland sea areas, and other enclosed bodies of water standards remain poorly met.

Rivers: 94.0 %

Sea areas: 78.6 % ) % Lakes: 53.2 % standards ( standards Samples meeting meeting Samples

Ministry of the Environment Year 3 Framework of measures for water environment improvement in Japan

Establishment of Environmental Standards on Water Quality National Government Target (Basic Environment Act)

・Establishment of effluent standards ( Control Act) National Government Uniform national standards

・ Measures for More stringent effluent standards (Water Pollution Control Act) Local governments industrial ・Regulations for private companies (Water Pollution Control Act) wastewater Measure, log and and notify effluent pollution status, on-site inspections → Penalties, order for remedies, other administrative guidance

・Investment in pollution control Private companies ・Efforts such as Human Capacity Development

Measures for ・Construction of sewerage (Sewerage Act) National and local domestic ・Installation of Johkasou (Johkasou Act ) etc. governments, Individuals wastewater

To formulate a “Plan for conservation of lake water quality” of each Measures for conservation designated lake in accordance with the Special Measures Act for Conserving Local governments of lake water quality Lake Water Quality (Lakes Act) and implement the conservation measures Ministry of the Environment 4 Act on Special Measures concerning Conservation of Lake Water Quality

Because lakes are enclosed bodies of water, water quality conservation in lakes requires measures more advanced than those in the other water bodies. Special measures, in addition to the regulations provided in the Water Pollution Control Act, are being taken in the lakes designated in accordance with “Lakes Act (Act No.61 of 1984).” Policy for the Conservation of Lake Water Quality (The national government selects lakes for the designation from all lakes in Japan) Governors of prefectures request the Minister of the Environment to designate lakes and areas (11 lakes including ) 11 designated lakes in Japan

Kamafusa Dam Reservoir (Miyagi)

Lake Nojiri (Nagano) Lake Hachiro (Akita)

Lake Suwa (Nagano) Kasumigaura (Shiga, Kyoto) (Ibaraki, Tochigi, Chiba) (Tottori, Shimane) (Shimane)

Inbamuna (Chiba) Teganuma (Chiba) Lake Kojima (Okayama) Ministry of the Environment 5 Lake Water Quality Conservation Plan (Lake Plan)

Lake Water Quality Conservation Plan for An example of effluent countermeasures area (Sanno each designated lake River Basin in Kasumigaura Catchment Basin) Formulated by local government, subject to approval by the Minister of the Environment after discussion in Conference on Environmental Pollution Control.

Pollutant load regulation In addition to concentration limits stipulated in the Water Pollution Control Act, daily load limits set

Infrastructure implementation Installation of sewerage, septic tanks, etc. and dredging, etc.

Designation of effluent countermeasures areas Priority implementation of diffuse-source countermeasures

Regulations on structures for small-scale animal husbandry and aquaculture in a lake and their use

Guidance, advice, recommendations to operators of facilities other than regulated facilities

Designation of protected areas around lakes Conservation of lakeside plants that help to purify water (Notification system for operations undertaken in areas around lakes)

Regulation of total amounts (when a further regulation is required)

Ministry of the Environment 6 COD and inflow load in Kasumigaura

Kg/day Kasumigaura COD

自然系 Naturally derived

市街地系 Urban 農地系 Agricultural 畜産・水産系 Animal usbandry/fisheries 産業・工業系 Commercial and industrial 生活系 Domestic

COD濃度(西浦) COD concentration （Nishiura） 濃度 北浦 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 COD ( ) 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 COD concentration （Kitaura） 8 8 8 8 8 8 8 8 8 9 9 9 9 9 9 9 9 9 9 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6

Note 1: The COD concentration in each lake is the average of the annual average COD concentrations observed at all water quality examination points in the lake (4 in Lake Nishiura and 2 in Lake Kitaura). Note 2: Since FY 2010, the load from chicken farms has been included in the animal husbandry and fisheries load. H net-cage aquaculture of carp resumed in the same year (no load from this activity in FY 2005).

Ministry of the Environment 7 Experience from measures implemented in lakes in Japan and future direction of the measures

１ Water quality control in catchment basins for conserving lake environment

◎ Accumulation of basic information through pollutant load monitoring, water quality monitoring, etc. ◎ Integrated implementation of wastewater regulation and measures for domestic wastewater with public works ◎ Extension and improvement of diffuse-source countermeasures

２ Target setting and implementation, extension and improvement of measures adapted to characteristics of lakes

◎ Formulation of a plan specific for each lake ・ To increase measures adjusted to characteristics of a lake (with a long-term vision, improvement targets and individual indicators) [Examples of individual indicators] Transparency (Lakes Suwa and Nakaumi), evaluation in lake environment survey based on human senses (Nakaumi, Lake Shinji)

◎ Improvement of poor bottom layer oxygenation, prediction of effect of climate change, implementation of adaptive measures to the change, etc.

３ Collaboration among people involved in lake water management and its promotion

◎ Continuation of concerted effort by local governments managing lakes and people concerned with lakes (local residents, fishermen, farmers, educational institutions, etc.) for the improvement of lakeside environment Ministry of the Environment 8 Thank you for your attention.

Ministry of the Environment 9