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  • Rillito Sediment Removal and Restoration Efforts

    Jun 17, 2016 | Read More News
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    Starting  in June, 2016, excess sediment will be removed from the Rillito River and relocated onto the river bank.  Over time, sediment deposits in the river have decreased the flow capacity and roughly 225,000 cubic yards will need to be removed to regain the lost capacity. Re-establishing the capacity of this channel is critical to prevent overbank flooding and protect public safety during future storm events.

    Clickable link to Rillito Sediment Removal Restoration PlanSeveral locations were evaluated as potential destinations for the sediment. Utilizing a piece of District-owned land locally referred to as the “Columbus Weed Patch” will save the Country taxpayers nearly $5 million dollars in haul costs alone.  Restoration of the Columbus Weed Patch site will begin immediately after construction. The first restoration phase will include contouring for water harvesting followed by path-side planting of additional native trees and installation of a decomposed granite walking path. It is expected that invasive species seed are present within the relocated sediment and will need to be treated for a period of two years. It is unknown which species and the quantity of seeds are contained within the sediment load.  The site can be re-contoured as need to promote stormwater harvesting.

    Once it has been determined that the site is relatively clear of invasive species, all disturbed areas not previously planted will be treated with a native seed mix that will replicate the adjacent areas. Eventually a diverse, multi-story vegetation communities will become established, promoting bird species, a variety of mammals, and small reptile communities. The outlet of the existing channel running along the west side of Columbus will be reworked to provide additional wildlife habitat amenities.

    For more information on the timing and effects of the sediment removal project, see the Rillito Sediment Removal press release.