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the above comments are applicable but I would offer the following advice.
True concrete can cure underwater provided it is confined and tremied into place. Concrete having a greater unit weight than water, will displace water, but if not placed by tremie, will be diluted by the surrounding water w/ a consequent loss in strength.
What the previous respondents have not mentioned is the design of your footing, walls and wing walls. Even “small” streams can carry large short-term flows. Water with sufficient velocity can scour even the best footing (Scolarie Creek in upstate NY scoured the footing to a NY state Thruway pier, result: bridge went kerplop and several motorists lost their lives). I’m not trying to compare your culvert to a NY State Thruway Bridge, only trying to make the point that you want whatever you build to last past the first significant storm event I’d advise you hunt up a standard detail from your state DOT (they are public domain) which can give you design guidance for wing walls, footings, retaining walls, culverts, etc. in your state.
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I want to put a stone wall around an 18-inch steel culvert I just put in on an intermittent stream that flows under my driveway. The wall height would be 3 feet from the streambed to the driveway. I want to pour a concrete foundation as a base for a rock wall that will face both side of the stream around the culvert. The stream flow can be reduced to a trickle. Can I pour concrete in a form as a foundation to the wall and have it cure hard in a wet streambed. Do I need to remove the form or can I let it rot? Do I need special cement for the concrete mixture?
*Kerry,Nothing unusual about your plan and from a concrete point, seems like it will fly okay.However......if this is a stream, you may want to contact your local authority on the subject first BEFORE you excavate, dam up, divert, modify, add, subtract or anything the stream.Gabe
*The Stream is an irragation run off ditch that drains 10 acres in the winter. My up stream neighbor has volenteered to cut his irrigation flow during construction.
*In that case, Kerry, your plan should work. Concrete cures even when surrounded by water as long as it doesn't wash out. Leaving the forms under the wall has little effect.The reason for the concern was that recently, a local 60 million dollar project was stopped in its tracks while the river authority determined if the run off stream (only runs in the spring) was classified as a navigable waterway. So, in the middle of summer, with virtually no flow, an officer of the authority, put a canoe into the water and tried unsuccessfully to navigate down stream, thereby allowing the project to proceed.Stupid laws are only amusing when you read about them, not when they cut into your pocket book.Best of luck with your project,Gabe
*Kerry, Gabe is correct on cautioning you. We have "ditches" in our area that are dry at times during the year, but may need to be reviewed by the county if they empty into a salmon bearing stream. These reviews can take months to complete, and are done on a "time" basis for billing. Fines and mitigation for damages to these wetlands can be very expensive. HV
*Concrete will be stronger if cured in water than out of water. As long as it does not wash away before it sets up it will cure much better than concrete poured above water. I see no reason leaving the form on would hurt but it wood will not rot if left permanently below the waters surface. Wood has to go thru wet/dry cycles to rot and this cannot happen under water. This is why stumps in the lake rot off at the waters surface and the part under the water stays for years.
*I have a question please.Is frost heave relevant in this circumstance?I didnt hear anyone say anything about depth of footers. Are footers needed here? If so, how deep?Hope this helps.
*The ditch empties into another irrigation canal which empties into a holding facility and the water is reused after settling. I was planing to make the forms tight against the bank. The foundation plan was 8 inches wide and high and as long as the distance between the culvert and the bank. Frost in not an issue where I live.
*the above comments are applicable but I would offer the following advice.True concrete can cure underwater provided it is confined and tremied into place. Concrete having a greater unit weight than water, will displace water, but if not placed by tremie, will be diluted by the surrounding water w/ a consequent loss in strength.What the previous respondents have not mentioned is the design of your footing, walls and wing walls. Even "small" streams can carry large short-term flows. Water with sufficient velocity can scour even the best footing (Scolarie Creek in upstate NY scoured the footing to a NY state Thruway pier, result: bridge went kerplop and several motorists lost their lives). I'm not trying to compare your culvert to a NY State Thruway Bridge, only trying to make the point that you want whatever you build to last past the first significant storm event I'd advise you hunt up a standard detail from your state DOT (they are public domain) which can give you design guidance for wing walls, footings, retaining walls, culverts, etc. in your state.
*A couple months ago, I was researching eco safe materials for floating docks. Another contractor suggested we use concrete. Seemed like a good idea until I checked with Dept. of Ecology. Here in Washington, they don't like to see concrete in fresh water because of lime leeching. Something to consider. - jb