Reche was advised the stream will be sprayed, but he's concerned what will happen if there's another significant rainfall before the spraying is done.
Palmerston North City Council chief infrastructure officer Tom Williams said the weed, commonly called parsely weed, grew in a number of streams in the area.
"The weeds grow profusely over summer and normally get flushed downstream after heavy rainfall events at the end of summer/beginning of autumn."
Williams said residents contacted the council after the last heavy rainfall two weeks ago.
"We have arranged to spray the weeds using Department of Conservation approved weed spray designed for use near waterways.
"After spraying the weeds we will re-assess the extent of the problem and remove the rubbish and poles that lie underneath the weeds.
"We are currently looking into whether we will need to spray this channel annually to control weed growth."
Williams continued: "It's really great when our community tells us about things like this, or if they ever see anyone dumping gardening waste or other rubbish near our waterways so we can remove them before they become a problem."
The Guardian asked the council the following questions. At the time of filing this story we had not received a response.
Does the PNCC know how healthy the stream is; ie the fishes, perhaps tuna/eels and other animals that live in this waterway?
Watercress was a traditional plant that grew in healthy waterways and the parsley weed seems to have replaced the watercress. Can anyone say why?