Implementation of earthquake measures
- In case of sewage infrastructures damaged, serious affects are given to peoplefs health and social activities, for example not only public sanitation problem and traffic problems but also no available of toilets etc.
- Sewage system is different from other life-line infrastructures and there is no other alternative method to function as like sewage system. Even though, earthquake measures have not completed in main facilities yet.
- By combination of two types of measures, the integrated measure is implemented, one is gProtectionh as earthquake resistant of main facilities the other is gMitigationh as minimization of damages with estimated earthquake situations.
Estimated damages by large earthquake and earthquake resistant of existing facilities
Serious affects in case of damaged sewage facilities
Proportion of earthquake resistant facilities constructed before 1997 when the interim guideline was applied (at the end of 2007)
Feature as life line of sewage system
Examples of damaged sewage facilities
Implementation of integrated measures
Implementation of integrated measures
Effectiveness of construction
- By earthquake resistant of sewer pipes, the function of flowing sewage can be kept at large earthquake
@Example: By soil improvement with cement solidification method, re-construction of sewer pipes after the earthquake in 2004 was done, as the result, there was no damage on the pipes at the earthquake in 2007
As the result of earthquake resistant, there was no damage at 2007 Niigata Tyuetu earthquake
Earthquake |
Magnitude
Dept (km) |
Damage of sewage facilities |
No. of tows |
Damage cost
(million JPN)
| Damages at WWTP |
Damaged
sewer line
(km) |
Niigata-Tyuetu
October 13 th , 2004 |
M6.8
Approx. 13km |
(Niigata Pref)
6 cities,
12 towns,
3 villages |
20,579 |
EMalfunction of wastewater treatment facility caused by broken inflow pipe at Horinouchi WWTP |
152 |
Noto-Hantou
March 25 th , 2007 |
M6.9
11km |
(Ishikawa Pref)
3 cities
3 towns |
1,882 |
|
15 |
Niigata-Tyuetu
July 16 th , 2007 |
M6.8
17km |
(Niigata Pref)
4 cities
1 town
(Nagano Pref)
1 city |
6,203 |
EFoundation pile of sludge treatment facility was partly damaged.
EDucts and pipes were broken
at Kasiwazaki WWTP |
53 |
Iwate-Miyagi Nairiku
June 14 th , 2008 |
M7.2
Approx. 8km |
(Iwate Pref)
2 cities
(Miyagi Pref)
1 city |
504 |
ECirculator of primary digester was broken at Mizusawa WWTP |
3 |
Remarkable damages of sewage facilities