classic waka stream

大井川井堰の音のなかりせば
紅葉を敷ける渡りとや見む
Roma-ji

Ōigawa iseki no oto no nakariseba momiji o shikeru watari to ya mimu

English Translation
On the Ōi River,
were there not the sound of water
at the weir,
I might think it a crossing
laid with a carpet of red leaves
Meaning
If there were no sound of water at the weir on the Ōi River, I would take it for a crossing paved with autumn leaves.
Commentary
Book Three Autumn Poems 248

The surface of the Ōi River is so thickly covered with leaves that, without the sound of water falling over the weir, the poet would mistake it for a crossing paved with leaves. The abundance of leaves filling the river is conveyed through the exaggeration that only the sound reveals it to be a river.
Poem 253 in this book also sings of the Tonase Falls on the Ōi River buried under falling leaves so that only their sound remains, sharing the conceit of leaves hiding water whose presence is revealed only by sound.
From poem 243 through poem 253 in this book come poems on autumn leaves, from trees just beginning to turn to leaves scattering until they fill rivers and waterfalls.
The author, Akisue, is Fujiwara no Akisue. A son of Fujiwara no Takatsune, he was trusted as a close retainer of Emperor Shirakawa because his mother had been the emperor's wet nurse, and he rose to Master of the Office of Palace Repairs. He founded the Rokujō Fujiwara house of poetry.

First line, 'ōigawa', is the river famous for autumn leaves; poems 245 and 253 in this book open with the same line.
Second line, 'iseki no oto no', uses iseki, a weir damming the river to draw water to the fields, for the sound of water falling over it. Poem 253 in this book also sings of the sound of water.
Third line, 'nakariseba', uses seba, the irrealis of the past ki with ba, forming a contrary-to-fact condition answered by mu in the final line.
Fourth line, 'momiji o shikeru', means paved with autumn leaves, ru being the attributive form of the continuative ri.
Final line, 'watari to ya mimu', means would I see it as a crossing, the particle ya joining the conjectural mu.
Author
Fujiwara no Akisue
Source
Kinyo Wakashu
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