Berthelot Holdings, LLC presented the 158 lot preliminary plate for Shadows in Manchac on April 11, 2012, receiving approval conditional on limiting backfill material to 18 inches “and structures to be built on pillars”. Ross Berthelot successfully appealed the conditions on May 9, 2012 and continued operations as usual, eventually finishing construction and washing his hands of any future problems. The plans included a retention basin, like most others, which has ceased to function as intended and now Ascension Parish is called upon to repair it.
One item appears on Monday’s EA drainage agenda:
Approval to enter into detailed easement / agreement negotiations with the Shadows of Manchac Subdivision HOA with respect to the redevelopment of the subdivision retention pond. Approval is for discussion only and the final decision is to be taken back to the East Ascension Drainage Board for a vote. (Commissioner Aaron Lawler)
Shadows in Manchac is located in District 7 of Lawler.
The cost of repairing its retention basin, which has apparently never been serviced, is $ 379,811.16 based on an estimate provided by Hartman Engineering. Obviously, the taxpayers who finance the EA drainage works will have to foot the bill or the retention basin will not be repaired.
Would the expense benefit drainage outside the subdivision? Otherwise, EA’s drainage commissioners must heed Louisiana’s constitutional ban on spending public funds to improve private property. Article VII, section 12:
A) Prohibited uses.Unless otherwise provided in this Constitution, funds, credits, property or valuable property of the State or of any political subdivision shall not be loaned, pledged or given to or for any person, association or company, public or private. . Unless otherwise provided in this article, neither the State nor a political subdivision shall subscribe or purchase the shares of a company or association or for a private enterprise.
One thing is certain, Ross Berthelot and his company will not give a penny to repair the retention basin they dug less than a decade ago. The standard operating procedure sees the developer create the HoA (which happened on September 10, 2013 in the case of Shadows at Manchac), with the responsibility being handed over to the residents once the houses were sold (which happened from 2018). None of the parties involved have been successful in maintaining the retention pond, and now the responsibility lies with EA Drainage (or not).
Hartman Engineering assessed the problem:
The original 2013 construction set of plans has been compared to a recent topographic elevation survey provided by Ascension Parish, and it appears that the retention basin has undergone sedimentation in areas throughout. from the pond. Sedimentation ranges from a few inches to over 18 inches in some areas. There are internal cross drains in the retention basin which are completely silted up. The existing rip-rap dams suffered severe erosion outside each dam. It is difficult to determine (by virtue of this work order and scope of existing work) whether the existing retention pond conditions adequately meet the original Ascension Parish design standards / ordinances without providing an assessment of more in-depth design. At this time, this is not part of our initial scope of work. However, I will say that this sedimentation has potentially reduced storage capacity to some extent, but overall it seems to be working as intended. In addition, there are two stone check dams that are severely eroding on the outer edge cutting the slope of the pond bank.
I made several site visits (April and May) after heavy rains and did not notice any street flooding or a full retention basin. Siltation will continue to worsen over time without any maintenance. There is an existing 30 ‘dedicated drainage easement that runs centrally along the retention basin.
The firm recommended the following corrective measures:
In order to properly maintain the entire retention pond, costs associated with dredging, cleaning and transporting materials would be the responsibility of HOA and Ascension Parish, unless Ascension Parish may acquire a temporary easement for access beyond the dedicated 30 ‘easement drainage. Ascension Parish can only legally clean the interior of the 30 ‘drainage easement. And, in my opinion, one shouldn’t be done without the other, which means that the entire retention pond (inside and outside of the 30 ‘drainage easement) should be brought back to the original design / plan conditions. Another option would be to dredge additional material beyond the original base of the retention pond so that the retention pond retains water (minimum 3ft deep) so as to minimize weed growth and trees. (See the attached photos of the existing pond on 07/26/21).
In addition, I recommend removing the riprap dam upstream and rebuilding downstream as planned with a center sheet pile wall extending into the existing side slopes of the pond bank to prevent scour / future erosion around the rockfill dam. Final elevations must be approved by an engineer.
If EA Drainage votes to pay for the Shadows at Manchac retention pond fix, how many other subdivision retention ponds will line up for the same largesse?