Under construction: Yadoriki Water Source Forest, Fall 2020 やどりき水源林

 

Now we know we have to learn to co-live with COVID-19. Kanagawa Forest Instructors Association has resumed our activity in Yadoriki Water Source Forest やどりき水源林 with new measures. When we guide the forest for visitors, we wear face masks and carry hand sanitizers. We check enough supply of soaps in toilets frequently … Having said that, actually, Yadoriki Water Source Forest is closed for its 4/5 coverage for the rest of the year.

The latest map for Yadoriki Watersource Forest.
 The area enclosed by black arrows are
 the only part we can enter now.

Kanagawa Prefecture decided to utilize this “with-COVID” situation when we are a sort of hesitant to go out. They are doing the civil engineering works to restore forestry roads that were destroyed last year by monster typhoons (; my post on November 1 and 22, 2019). The prefecture is also busy in forestry for the afforested area, especially in the westside of Yadoriki Stream. That was a part devastated by the typhoons last year. They are clearing the broken trees. In addition, the contract foresters are thinning the forest for the “fittest” cedars and cypresses, hoping they become large enough trees to secure the soil against future huge storms.

Restoration work for the embankment of the Open Space.
 I guess, their idea is piling up huge rocks along the bank
 would lessen the damage of flush flood.
 Er … let us see.

So, trucks loaded by rocks are busy commuting
 between the forest and some depot for rocks.

Especially during Monday to Saturday, when you visit Yadoriki Water Source Forest now, you will be greeted by thunderous noise of road constructions, for creation of embankments, and of thinning chainsaws … It’s totally up to you to enjoy the scenery, or not. Yeah. The noise is not non-stop for sure. That’s the difference between the construction works in city center and in deep forest … We forest instructors are a bit sad to find our beloved hazelnuts trees were cut to make a new forestry road. My seniors were also disappointed a pillow lava, which they polished to confirm its crystalized surface due to its formation millions of years ago, was thrown away as a trash … The area where we instructors have been doing the forestry is now inaccessible due to bulldozers. *Sigh*

Where is the polished lava?

The Prefecture plans to end all of these hubbubs by the end of the year. We are waiting now … Anyway, by the time the new forestry roads are ready in Yadoriki Forest, we may have some remedy against COVID-19. Let’s be patient and keep crossing our fingers.

If you find environmental issues in Kanagawa Prefecture, please make a contact with Kanagawa Natural Environment Conservation Center 神奈川県自然環境保全センター

657 Nanasawa, Atsugi City, 243-0121
〒243－0121　厚木市七沢657
Phone: 046-248-0323

You can send an enquiry to them by clicking the bottom line of their homepage at http://www.pref.kanagawa.jp/div/1644/

Disturbance: Typhoon Hagibis for Yadoriki Water Source Forest

Yadoriki Water Source Forest やどりき水源林 also had substantial disturbance by Typhoon Hagibis. At this moment, the Forest is off limit for visitors, and the gate for the forestry roads to Yadoriki Forest is locked. As of November 1st, after Hagibis, the area had two more long torrential rains, and numerous mini squalls. Yadoriki Forest’s recovery from the Hagibis is unpredictable at best.  We Kanagawa Forest Instructors have not received information from the Prefectural Office when the gate is open ... This week, I report you scars I’ve found in Yadoriki two weeks after the visit of Hagibis. I hope you could have some idea about the situation.

The way Nakatsugawa River 中津川 / Yadoriki Stream 寄沢 flows has changed. Above photo was taken at the point before Hadano Forestry Road begins. The river goes around nearer to the banks so that many points have collapsed by strong rains from Hagibis and others. (Oh, yes, Nakatsugawa River and Yadoriki Stream are the same flow. It changes name at Yadoriki Bridge 寄大橋.)

Mini landslides are here and there along the community road from Yadoriki community 寄 to the gate of Yadoriki Water Source Forest. It would take a couple or so of dry months before the soil stabilizes. As we have to think the effect of frost and frozen ground during winter in this part of our prefecture, it may be difficult to expect the situation improves quicker. If you plan to drive to red Yadoriki Bridge, please be very careful.

Red Yadoriki Bridge over there.
 Could you see a large log was caught by the weir?

Inside the gate for Yadoriki Water Source Forest, the road condition is worse. Its forestry road which was passable for a city car before is now for off-road types only.

It seems to me
 animals are taking the advantage of
 human-less environment in Yadoriki now.

Yadoriki stream inside the Yadoriki Water Source Forest has changed its shape drastically after the rains. It destroyed trekking roads along the stream from the gate and eroded the open space. It seems to me substantial amount of large rocks and logs were carried by the flood to the downstream.

Destruction

It’s a matter of time before these picnic benches are gone.

Forestry road in the Water Source Forest collapsed in the middle. So, beyond this point it is strictly closed for the unauthorized visitors. The soil was washed away below the asphalt.

Here and there, Yodoriki’s utility forestry roads are covered by landslides like this. Though, these points could be cleared soon as the season of logging is approaching.

And cones of conifers promptly utilize the chance
of sunshine for sprouting thanks to the land collapses.
 Mini-forest. Cute.
 (And they will be gone quickly by the next slide …)

It seems to me Hadano Forestry Road 秦野林道 also has large disturbances due to these rains by typhoons and others. The streams along the road certainly experienced large flows and landslides. This is Teshiro Stream 手代沢. Before we could not see the waterfall from the forestry road. Now both sides of the valley collapsed and trees that concealed the vista were broken or washed away. Yeah, the view from Teshiro Bridge 手代橋 is nicer now, but can the bridge last when the next big storm comes?

Map of Hadano Forestry Road

Above is a stream that is filled with soil avalanches. This is a naturally made dam creating a pond whose surface was just few inches below the paved forestry road. I will not be surprised if Hadano Forestry Road collapses here when the next large rain comes.

Majority of Yadoriki Forest is owned by the Prefectural Government so that how to deal with the situation is, in the end, totally up to the budgetary condition of Kanagawa Prefecture 神奈川県. Geologically Tanzawa mountains are very fragile. (More to this soon.) Scars in the forest by 2019 storms can easily expand. They may turn into debris-avalanche that would swallow human settlements downstream … I don’t know. I’ve heard all the people in Yadoriki Community inherited a warning from their ancestors, saying “When the water of Nakatsugawa River turns white, run!” Fingers crossed.

If you find environmental issues in Kanagawa Prefecture, please make a contact with Kanagawa Natural Environment Conservation Center 神奈川県自然環境保全センター

657 Nanasawa, Atsugi City, 243-0121 

〒243－0121　厚木市七沢657

Phone: 046-248-0323

You can send an enquiry to them by clicking the bottom line of their homepage at http://www.pref.kanagawa.jp/div/1644/