Date of interview: Sunday, 04/20/2014

Sanaka Dam is an earth dam for irrigation in Tambasasasayama City, Hyogo Prefecture, and is one of four dams (Sanaka Dam, Tsubakuichi Dam, Hachimantani Dam, and Fujioka Dam) constructed as part of the prefectural irrigation and drainage project as part of the Sasayama River Coastal Land Improvement Project Plan.

downstream face of embankment

しっかりと草刈りがされていてきれいな堤体下流面です。また下流はハイマート佐仲というオートキャンプ場があり、この日も多くのキャンパーで賑わっていました。正直写真が撮りづらい💦

View of the top edge from the left bank

This is the top of the mountain where you can feel the afterglow. Incidentally, although cars are allowed to pass through the skyline, the right bank road seems to have turned into a dirt road from the halfway point, so it is not recommended to drive there.

Looking downstream from the top

The auto campground downstream that makes you wonder how you were in that place earlier. At night, the campers' lights seem to create a fantastic atmosphere.

View of the dam lake from the top

This is a small reservoir. The small white building on the right side of the photo is the water intake facility, and the Sanaka Dam fishing pier can be seen in the back.

View of the water intake system from the top

The water intake system is a common slant-flume type.

Sanaka Dam Fishing Area

There is a managed fishing area upstream of the reservoir that can be enjoyed in combination with camping. It is said that spoonbills and wakasagi can be caught.

Stone monument "Shimizu Renshin

A stone monument erected to commemorate the completion of the Sanaka Dam. It appears to have been written by the governor of Hyogo Prefecture at the time.

View of the spillway from the top

The spillway is a side channel type of the type often seen in earth dams.

View of the conduit from the top edge

The spillway is located on the right bank. The spillway is usually built on top of the ground, but it is hidden from view, perhaps because it is easy for plants and trees to grow.

View of the spillway from the top

It is a relatively clean afterdrainage basin, although moss is growing on it.

View of the upstream face of the embankment and the spillway from the right bank

A stone monument can be seen between the spillway and the embankment, which may have been made this way due to the presence of a landslide up to this point.

It is a very ordinary earth dam for irrigation, but it was a Sanaka Dam where camping, fishing, and other recreational activities can be enjoyed.

Sanaka Dam Specifications

Location	Kosaka, Tamba Sasayama City, Hyogo Prefecture
River Name	Kosaka River, Kako River system
Objective	A (irrigation water)
Model	E(earth dam)
Bank height	38.9m
Bank length	144m
Dam volume	282,000 m3
Watershed Area	2km2
Reservoir area	4 ha
Total storage capacity	505,000 m3
Effective water storage capacity	450,000 m3
Dam operator	Hyogo prefecture (Kinki area) (Hyougo)
Main body constructor	-
Year of launch	-
Year Completed	1967.
Name of Dam Lake	1978

Other facilities/observations

There is no parking lot, so you will have to park on the shoulder of the road. You will probably have to use the restrooms at the campgrounds and managed fishing areas. Fishing without permission is prohibited as fishing rights have been established.