We will introduce the utilization of groundwater (renewable energy) in Gunma Prefecture from various perspectives.

Overview of groundwater and groundwater heat utilization in Gunma Prefecture

When promoting the use of groundwater and groundwater heat, the most important thing is the availability of groundwater.
This page summarizes the groundwater situation in Gunma Prefecture and useful groundwater-related websites.

*This information is current as of November 2018. Please check the latest information when making your decision.

Ordinances on groundwater use

The first information you should check is each local government's ordinance regarding groundwater pumping.
When using groundwater, you must submit a notification and comply with regulations regarding the amount of groundwater to be collected and the diameter of the well, etc., in accordance with this ordinance.
In general, although notifications and water withdrawal reports are required over a wide area of the prefecture, it is relatively easy to use groundwater in the prefecture.

●Prefectural-wide: Gunma Prefecture Ordinance for Preserving the Living Environment *1
Wells with a discharge cross-sectional area of 19 cm2 or more (pipe diameter of 50A or more) are considered "specified pumping facilities."Notification and annual water withdrawal reports are required.
However, this does not apply to agricultural use where the strainer is less than 50m deep, hot springs, etc.
In principle, there are no restrictions on the amount of water intake or the cross-sectional area of the discharge port.However, guidance may be given by the government.

*1 The target areas are Maebashi City (excluding the areas of the former Ogo Town, the former Miyagi Village, the former Kasukawa Village, and the former Fujimi Village), Takasaki City (excluding the areas of the former Kurabuchi Village, the former Minago Town, the former Gunma Town, the former Shinmachi Town, the former Haruna Town, and the former Yoshii Town), Isesaki City (excluding the area of the former Akabori Town), Ota City, Tatebayashi City, Tamamura Town, Itakura Town, Meiwa Town, Chiyoda Town, Oizumi Town, and Oura Town.

●Municipalities with their own regulations: Naganohara Village, Oura Town, Takayama Village, Tsumagoi Village, Meiwa Town
The content generally follows the prefectural ordinance, but you should inquire in advance.

●Other
Depending on the region, associations and other groups may have their own rules.
Please be careful if this affects agricultural associations, hot spring associations, industrial complexes, etc.

<Link>
List of ordinances and regulations on groundwater extraction in Gunma Prefecture (Ministry of the Environment)
https://www.env.go.jp/water/jiban/sui/j10.html
Overview of pumped storage facilities (Gunma Prefecture)
href=”http://www.pref.gunma.jp/04/e0900173.html

Wastewater Ordinances and Regulations

● Water quality standards for discharged water
When groundwater used in a factory or business is discharged into a drain or river, in addition to complying with the water quality standards set out in the Water Pollution Control Act, in Gunma Prefecture it is also subject to regulations set out in the Gunma Prefecture Ordinance for the Preservation of the Living Environment.
It is rare for groundwater itself to exceed the standard values, but it is necessary to check in advance.

●Discharge into the sewer system and sewerage fees
When used groundwater is discharged into the sewer system, a sewerage fee is charged according to the amount discharged.
When groundwater is used as drinking water, sewerage charges are generally determined based on the water intake meter.
However, if groundwater used as a heat source is discharged into a drain or river, it is often possible to have it not counted in sewerage charges by checking with the local government in advance.

●Other
Depending on the region, associations and other groups may have their own rules.
Please be careful if this affects agricultural associations, hot spring associations, industrial complexes, etc.

<Link>
Wastewater quality standards (Gunma Prefecture)
http://www.pref.gunma.jp/04/e0900062.html
Overview of the sewerage system (Gunma Prefecture)
http://www.pref.gunma.jp/06/h6610020.html

Groundwater Resources

Gunma Prefecture is located in the middle and upper reaches of the Tone River, which has the largest drainage area in Japan, and is roughly divided into a mountainous area in the north and a plain in the south.

With abundant water provided by mountain ranges such as Mount Akagi, Mount Haruna, and Mount Myogi, the area is relatively rich in groundwater throughout the prefecture, making it an ideal area for utilizing groundwater.

Although there are regional differences, there are multiple aquifers within a depth of 100m, and in terms of water quality, good quality water can generally be secured in the northern mountainous regions.
Although there are regional differences, even in the plains, groundwater has been used for domestic, industrial and agricultural purposes since ancient times.

Meanwhile, in urban areas, land subsidence has been confirmed in some areas due to excessive pumping during the period of high economic growth, and the prefecture is conducting monitoring.
In mountainous areas, the water reaches bedrock at a relatively shallow depth, and there are cases where a sufficient amount of water cannot be obtained.

Gunma Prefecture as a whole can be said to be an area that is generally suitable for utilizing groundwater.
However, groundwater reserves can change slightly depending on location.
An investigation by a specialist institution is required to determine whether water can actually be drawn from the facility.

<Link>
The following website provides information on groundwater aquifers and geological information.
*As the content is highly specialized, we will provide support when viewing it.

Groundwater Map (Ministry of Land, Infrastructure, Transport and Tourism)
http://nrb-www.mlit.go.jp/kokjo/inspect/landclassification/water/w_national_map_cw.html#803
Mapping Gunma
http://mapping-gunma.pref.gunma.jp/pref-gunma/Agreement?IsPost=False&MapId=94&RequestPage=%2fpref-gunma%2fPositionSelect%3fmid%3d94