Each pond, lake or reservoir or other impoundment of water that covers or is proposed to cover a surface area of one-quarter of an acre or greater shall meet or exceed the standards and regulations set out herein.
(a) Definitions. For the purposes of this chapter, the following words shall be defined as follows:
(1) “Embankment pond” means a pond made by building an embankment or a dam across a stream or watercourse.
(2) “Excavated pond” means a pond made by digging a pit or dugout in nearly level areas.
(3) “Mixed pond” means a combination of an embankment pond and an excavated pond built in gentle to moderately sloping areas where the capacity of water is obtained by both excavating and by building a dam.
(4) “Pond” shall include ponds, lakes, reservoirs or other impoundments of water.
(5) “Surface area” means the area covered when the elevation of the pond reaches the emergency spillway elevation.
(b) Soils. Soils for all three types of ponds must be suitable to hold water. Soils must contain a layer of material that is impervious to water movement and thick enough to prevent excessive seepage. Fine textured clays or silty clays or other soils deemed sufficient by the City Engineer must extend well below the proposed pond depth. The City Engineer may require the testing of soil samples to insure that the soil is sufficiently impervious for the construction of the proposed pond and to prevent seepage.
(c) Size. The size of the watershed must be approved by the City Engineer. The bottom of the pond shall be at least six feet deep for fifty percent (50%) of its area or eight feet deep for twenty-five percent (25%) of its area.
(d) Pollution. The pond must be designed such that any pollution will be minimized by selecting a site where drainage of septic systems, farmsteads, canals, dumps and other pollution cannot reach the area.
(e) Safety. The pond shall not be located in an area where the failure of the construction could cause loss of life or injury to persons, property, livestock, highways, or interrupted use of service of public utilities. The pond shall not be located in utility easements.
(f) Excavated Soil. All excavated soil from a pond must be disposed of properly and, if required by the City Engineer, removed from the site.
(g) Ponds. Shall be fed by surface runoff, groundwater aquifers or a combination of both.
(h) Dimensions. The side slopes of a pond shall be no steeper than the natural angle of repose of the material being excavated in order to prevent slippage or 3:1, whichever is greater. Where surface water enters the pond from a natural or excavated channel, the side slope of the pond must be protected against erosion by grading it to a slope no steeper than 4:1 and protected with grassy vegetation, or with a structure.
(i) Groundwater Aquifers. If the primary source of water to fill the pond is from a groundwater aquifer and the groundwater table during the low ground water period of the year is over four feet deep, no pond is permitted. The City Engineer may require testing to insure compliance with the groundwater table. Where surface water enters the pond from a groundwater aquifer, the side slope of the pond must be protected against erosion by grading it to a slope no steeper than 4:1 and protected with grassy vegetation, or with a structure.
(j) Information Required. A new or altered pond requires a detailed engineering survey computing the expected flow of water into the pond; setting elevations for earth spillways, pipe spillways and the top of the dam or embankment; determining the dimensions of the dam, embankment and spillways; establishing the degree of slope of the sides of the pond; calculating how much earth fill and other materials are required; an erosion control plan; and prescribing construction methods and procedures.
(k) Spillway. All ponds require two spillways for passing the overflow when the pond is full. A pipe spillway through the dam and an emergency spillway shall be used together. Proper construction material and a detailed cross section of the emergency spillway as approved by the City Engineer is required for the pipe spillway.
(l) Pond Safety. The owner of any pond is responsible for keeping it safe and sanitary and maintaining it in a proper and safe manner. In this respect all ponds must follow these minimum regulations:
(1) The water and surrounding area must be kept free of stumps, brush, rubbish, wire, discarded machinery, junk and loose items that can be used for swimming or floating.
(2) If the pond is two feet or deeper at its deepest point, the owner shall place warning signs at all danger areas in conformity with the signage set out in Appendix A, attached hereto and incorporated herein.
(3) If the pond is two feet or deeper at its deepest point, the owner shall place a general warning sign as set out in Appendix A approximately every 100 feet along the top of the slope. The owner shall also place near the area lifesaving equipment such as ring buoys, ropes, planks and large poles on the shore near the water in conformity with Appendix B, attached hereto and incorporated herein.
(4) If the pond is used for or likely to be used for ice skating, the owner shall place a long plank or ladder near the area for rescue operations.
(Ord. 1998-103. Passed 5-15-00.)