Frog Bottom Ponds

This site discusses ponds on the "Frog Bottom Nature Reserve" (FB).

The sites objective is to share information and practices effective in "re-wilding" - returning land to a condition more hospitable to native plants, insects, aquatic animals and birds. There is extensive documentation at an academic level, and often has many helpful details. What was missing for me was case histories where these concepts were actually applied. This site shares information used to make management decisions, and how those decisions were actually conducted.

There were several individuals providing helpful recommendations for the ponds:

Ronnie Marek and Floyd Nauls, both with the NRCS, are pond construction experts and provided good technical recommendations for the Upper Lynn Lake rebuild.
Dr. Todd Sink and Brittany Chesser are with the Texas A&M Agrilife program and helped me understand the importance of water chemistry and how to manage water quality.

Pond Conditions when Purchased

There were two ponds on the property: a small "mud hole" in the Horse Pasture, and a sanded-in 1/2 acre pond in the Front Pasture.

Pond locations

Upper Lynn Lake (Original Pond)

This is the original, approximately 1/2 acre pond. It had a number of issues. There are air photos from the 1960's showing the pond - that makes it at least 60 years old, likely 20-30 years older older. Also, cows had access to the pond - it was the primary water source for the large numbers of cows stocked on the property. This resulted in deterioration of the berms from trampling and large amounts of cow urine and excrement directly into the water. Trees were not removed from the berms, allowing roots to penetrate the berm material and create weak spots. There was no sediment catchment upstream of the pond, so any mobilized sand ended up in the pond. Soundings found a maximum depth of 4-5 feet.

We decided to drain the pond and remove the sand. This involved cutting the berm, draining the pond, letting the material dry for several months, then mobilizing a large excavator, bulldozer and dump truck to remove the sand and haul to a back pasture for spreading.

While the pond was drained, additional structures would be added:

A forebay upstream of the main pond to collect large sediment particles before they can enter the main pond.
An aquatic shelf. This is a 6-10 foot wide bench around the inside circumference of the pond, located 1-2 feet below the water surface.
Reduce the height of the berm to 2 feet above the water level, and slope the sides to a maximum 20 degree angle to allow mowing the berm with a tractor. The 20 degree angle reduces the chance of a roll-over.
Add a secondary outlet, 1/2 foot higher than the primary outlet.

This is a key conceptual drawing that many good ideas were identified from.
This is the sketch used for pond reconstruction. Key notes include: Adding a forebay, to collect sediment before it gets into the main pond. Adding an aquatic shelf. Specifying places to access for picnics. Having a secondary outlet for very high water inflow events.


Spillway between the forebay and the main pond complex. The elevation of the spillway is the same as the main pond primary outlet. This is to minimize the potential for erosion from the moving water when it enters the main pond. We used "rip rap" rock, 4-6 inches in diameter to help the berm resist erosion from water flowing across it. The spillway can also be crossed with trucks, tractors and "Hondas" (ATV's).

Spring Lake (in Horse Pasture)

The original Circle Spring. Heavily impacted by cattle wading inthe pond - basically a mud hole.	The original Circle Spring. Heavily impacted by cattle wading inthe pond - basically a mud hole.

Lower Lynn Lake (New Pond)

The original Circle Spring. Heavily impacted by cattle wading inthe pond - basically a mud hole.	The original Circle Spring. Heavily impacted by cattle wading inthe pond - basically a mud hole.

Pond Conditions when Purchased

Upper Lynn Lake (Original Pond)

Spring Lake (in Horse Pasture)

Lower Lynn Lake (New Pond)

Water Management