Due to the outstanding negative impacts of the massive earthquake and tsunami on infrastructures such as coast and river levees, in addition to land subsidence and inundation across wide areas, the afflicted areas have become dangerous and prone to having secondary disasters (e.g. aftershocks and the accompanying tsunami, high tides, heavy rains, storm and sediment disaster).

Facing these problems, MLIT has promoted measures to prevent secondary disasters in seasons of snow melting, early summer rain, and typhoons by investigating land subsidence due to the earthquake via aerial laser measurement, evaluation of and the announcement of risks for secondary disasters, and the effective draining of the afflicted areas by drainage pump vehicles deployed nearby.

53: Reconstruction Schedule concerning the Prevention of Secondary Disasters

April	May	June	August	September	October
Flood season	Snow melting season	Rain season	High tide season
Evaluation and announcement of secondary disaster risk (considering the fact that area safety has declined because of the Great East Japan Earthquake)	Monitoring
Drainage of inoculated areas	Urgent drainage
Tidal wave control	Recovery of coastal breakwaters	Emergency measures (sandbag build-up to a level of tidal wave)
3 prefectures (Iwate, Miyagi, and Fukushima)
All	Fully- or half-destroyed	Temporary managed location*	Implemented
Extension of coastal protection (km)	About 300	About 190	About 50	About 19
* Sections where important public facilities are protected
Actual reconstruction (restoration with embankment, reconstruction of breached bank protection, etc.)
Management of rainstorms and floods	Measures for warning and evacuation	Lower standards for calling out water company and for announcement of flood forecasts for designated rivers, rainstorm warnings (inundation, etc.) and flood warnings, announcement to residents, etc.
* Adjust depending on situations
River levee/Infrastructures for rivers (floodgates, watergates, etc.)	Temporary measures (Temporary reconstruction of levees by embankment, etc.)
Affected location (directory controlled)	Temporary managed location*	Implemented	Affected location (directory controlled)	Actual reconstruction
Tohoku	1,195	29	29	By the end of June 2011
Kanto	920	24	24	By the end of June 2012
Total	2,115	53	53	Total
Sediment disaster control	Measures for warning and evacuation	Investigation of details (check-up on location in risk of sediment disaster)
All	Implemented	Review of current situations (A/B)	Lower standards for announcing warning information for sediment disasters, rainstorm warnings (landslides), etc.; strengthen vigilance with landslide sensors, etc.
Checked locations	33,301	32,302	1,143
* Check-up has been completed, except in some areas where operation is not possible (traffic-blocked areas or affected areas by nuclear power plant accidents in Miyagi and
Development of sediment control facilities	Temporary measurement (sandbag buildup, etc.)
At locations where a landslide occurred during the earthquake, start urgently constructing sand erosion protection.
By rainy season *1	By typhoon season *2	*1 Locations where landslide etc. occurred in the earthquake. (As for Disaster-related project for sediment control, it is planned to be finished around the end of FY 2011.) *2 Locations holding danger of secondary landslide etc. (As for temporary extra budget, the operation is planned to be finished around the end of FY 2011.)
Constructing sand erosion protection (points where operation started)	18	24

Source: MLIT