I cant see that sucking hard enough to work without Making a venturi booster on the end of the hose (still may not work but would be cool if it did). I contemplated mentioning a compressed air line up to the inlet so you could remotely start the syphon but it seemed too complicated.Even simpler would be a hose from the low spot into the downspout. When it rains, Bernoulli will do thee sucking to start the draining.