Any application to develop a stormwater retaining system out of necessity, or other water impoundment facility for aesthetic purposes only, shall include a complete set of plans prepared to the following specifications and containing the following information.
(a) A site plan drawn to a scale of not greater than one inch equals fifty feet shall be prepared by a licensed civil engineer, whose seal shall appear on the plan, which plan shall include:
(1) A north arrow, a legal description of the property on which the facility is to be located, the name, address, and phone number of the owner and the developer, and the name address, and phone number of the designer.
(2) The location and identification of all existing and proposed in-ground and above-ground utility easements involved with the immediate site, i.e., the ground upon which the facility itself is to be developed.
(3) A cross-section of the basin showing the side slope, the rampway system, if applicable, and the bottom of the basin.
(4) The location, type, and size of all landscape planting materials and the location of the fence, when required, and the gate opening with the type of gate to be used. Where the standards of this chapter require fencing, a cross-section of the fence, fence post with footing, and landscape panel with landscaping, shall be included.
(5) Where applicable, the location of all existing or proposed buildings that will be located within twenty-five feet of a basin.
(6) The location of all existing or proposed off-street parking spaces that will be located within twenty-five feet of an unfenced stormwater basin and within eight feet of a fenced basin.
(7) When a stormwater retaining facility is to be part of a new development that requires review and approval of a site plan, as set forth in Section 1298.07 of the Zoning Code, all drawings for the basin shall include the requirements of this chapter but may be made a part of a required site plan package for the development.
(b) Calculations to determine the total storage volume of the system shall appear on the site plan and shall be determined in accordance with the Wayne County Stormwater Standards Manual.
(c) Except as otherwise permitted and regulated herein, the maximum side slope of a stormwater basin shall not be steeper than a ratio of six to one, (six feet of the horizontal plane for each foot of vertical rise). When any stormwater retaining basin is to have a side slope steeper than six to one, the facility shall be subject to the following requirements.
(1) A site plan prepared in accordance with the requirements of subsection (a) hereof, shall be submitted.
(2) The basin shall be in an interior side or rear yard, except where site conditions, such as topography, required direction of site drainage flow, or other conditions recognized by the City Engineer, require locating the basin in an exterior side yard or front yard.
(3) The side slope of the basin shall be stabilized against erosion and landslide by means and materials acceptable to the City Engineer.
(4) The bottom slope of the basin shall not be less than one percent.
(5) The retention basin shall be provided with a ramp that will permit access to the bottom of the basin by motorized machinery, for maintenance purposes.
(6) The basin shall be completely fenced by a green color-matched, close-like, non-climbable, maximum security-type, chain-link fence. The fence shall be not less than eight feet in height and shall include a ten-foot-wide swinging or roll away-type of the gate. The vertical posts of the fence shall be anchored in concrete footings that shall be at least forty-two inches deep, measured from ground level at the post. There shall be provided at the bottom of the gate a concrete footing to permit a positive securing of a swinging gate at the closed position or a concrete rollway for a sliding gate.
(7) The fence shall be located on a line parallel to and not less than one foot from the rim of the basin and shall include signs posted at proper intervals, but at least on each side of the basin, warning of danger and prohibiting trespassing. Such signs shall be no greater than two square feet in size and shall be made of permanent material, affixed securely to the fence.
(8) A landscape planting panel shall be provided on all sides of the basin. The panel shall be placed outside of and adjacent to the fence. The panel shall be at least five feet in width, except that where the panel is adjacent to off-street parking spaces, minimum width of eight feet shall be provided. The landscape panel shall be fully planted with a minimum of evergreen shrubs. Where a screening effect is desired, narrow evergreen trees shall be used in place of the shrubs. Evergreen trees may also be used in combination with shrubs when a screening effect is not desired.
(9) In those instances where ground constraints preclude application of the five- or eight-foot-wide landscape panel, a one-foot-wide planting panel may be used in which vines may be planted that will grow up the vertical face of the fence. Whenever this type of landscape screen is used, a horizontal top bar, to which the top of the fence shall be attached, shall be employed and shall be secured to the vertical posts. All plantings used shall be consistent with the landscape planting standards set forth in Section 1298.09 of the Zoning Code. Use of this alternative will require approval by the City Engineer. The Engineer, in deciding as to the applicability of this landscape planting alternative, shall find that the constraints of the site on which the basin is located clearly preclude the use of the wider planting panel. The City Engineer may request the input of the City Building Department and other City departments or consultants in making his or her evaluation.
(d) When a stormwater retention or detention system is to serve as a visual aesthetic feature of the site, whether it is required by necessity or not, it shall be made an integral part of the landscaping of the site and shall be subject to review and approval by the City Engineer. The City Engineer, in reviewing the plans, shall find that the following minimum requirements are met.
(1) A site plan drawn to scale and prepared by a licensed engineer shall be submitted and shall contain all design information applicable to this type of basin as herein set forth and as set forth in subsection (a) hereof.
(2) The maximum side slope of the basin shall not be steeper than a ratio of six to one (six feet of the horizontal plane for each foot of vertical rise).
(3) No part of any basin shall be located closer than twenty-five feet to any structure, right-of-way, parking lot, or lot line.
(4) The bottom of the basin shall maintain a slope ratio as set forth in paragraph (c)(5) hereof, and when designed to serve as a stormwater detention system the bottom shall consist of grass so that when not underwater, it shall serve as part of the site's lawn area.
(e) With the exception of unfenced basins designed as an integral part of a site's landscaped lawn area, stormwater entering any fenced basin shall enter only through sewer inlets. The sides and the rim of these basins shall be constructed to keep stormwater runoff from draining directly over the sides into the basin.
(f) All stormwater retention systems shall include devices and or systems designed to effectively circulate water and/or to evaluate water so as not to create an unsightly, obnoxious, or unhealthy water content. All such systems shall be subject to review and approval by the City Engineer.
(g) Whether or not stormwater retention or detention system serves as a visually aesthetic feature of the site, no part of any basin shall be located closer than twenty-five feet to any structure, right-of-way, parking lot, or lot line.
(Ord. 22-1028. Passed 10-19-22.)