Alternative Water Sources

ALTERNATIVES:  How could the amount of water to be drawn from Lake Conroe in the future be reduced?  “Alternatives” include:

  • Water conservation will be an integral part of reducing the amount of water drawn fromLakeConroe.  If we use less water, then we won’t have to draw as much.  Since a maximum of 100,000 acre feet per year can be drawn fromLakeConroeand more water than that will be needed someday, water conservation will be with us forever.  For a separate discussion of this, see “Water Conservation” below.
  • Utilizing waste effluent from treatment plants for irrigation will reduce our water use.  In summer months, it is estimated that 60% of our residential water use goes to irrigation (watering your yard and landscape).  In the winter, that estimate is 30%.  While it may be difficult to convert existing subdivisions and commercial development into users of effluent for irrigation (since the construction and infrastructure is already in place), new construction could much easier accommodate the use of effluent for irrigation by incorporating this concept into the planning stage of that development.
  • Further consideration must be given to Judge Sadler’s proposal of building two new reservoirs to capture water that would otherwise be released over the dam on Lake Conroe or lost elsewhere during periods of heavy rainfall.  Conceptually, these two reservoirs would capture water before it gets toLakeConroe.  If Lake Conroe were not full (at the 201 feet level), then the water would be allowed to flow into Lake Conroe.  If Lake Conroe were full and excess rains would be otherwise released downstream, these reservoirs would capture the water behind dams and hold it there until Lake Conroe needed it to fill the lake to the 201 feet level (normal pool elevation).  Clear obstacles to this proposal include the procurement of the land for the creation of the two reservoirs (some of which would have to come from the Sam Houston National Forest) and the multitude of environmental concerns related to such a project.  The cost of such a project has not yet been determined.  SJRA has agreed to conduct a feasibility study of this proposal, but a study date earlier than 2015 has not been agreed to yet by SJRA.  Approvals for and construction of such reservoirs would probably take a minimum of 20 to 30 years (remembering that our County’s water needs will be here forever).
  • Many have suggested that an “alternative” might be building a reservoir between Lake Conroe and The Woodlands which captures all water released over the dam atLakeConroe.  This “alternative” has been discounted based on the lack of a suitable site.  To be cost effective and practical, this reservoir would require too much land given the lack of undeveloped land between Lake Conroe and The Woodlands.

Grass Carp (White Amur) Solution

Origin and Biology of Grass Carp (White Amur)

The grass carp, also known as the White Amur (Ctenopharyn-godon idella), is a Chinese carp imported into this country as a means of achieving biological aquatic weed control. It is native to southeast Asia, and was brought into the United States in the early 1960’s as an experimental aquatic weed control method. Since that time, use of grass carp has become commonplace. Triploid Grass Carp are specially produced in hatcheries and possess three sets of chromosomes instead of the normal two. This abnormal condition causes sterility, so these are the only exotic fish that can be legally used for aquatic weed control in most states. A permit is usually required for possession and use of Triploid Grass Carp. Because they cannot reproduce, the number of fish present in an area can be regulated.


Feeding Habits

Until they are about 2 inches long, grass carp feed almost exclusively on microscopic animals called zooplankton. They become dedicated vegetarians, however, after they reach a length of about 4 inches. The amount of vegetation they will consume depends upon several environmental conditions, such as water temperature, water chemistry, and the kinds of plants available. Consumption rates also vary with fish size. For example, until they reach weights of about 6 pounds, grass carp may eat 100 percent of their body weight in vegetation per day. (This is equivalent to a 150-pound human eating 150 pounds of food per day.) As they grow larger, consumption decreases; up to about 13 pounds, they will eat 75 percent of their body weight per day, and above 13 pounds, they slow down to about 25 percent of body weight per day.


Other Considerations

Grass carp are a viable and economical means of controlling the growth and spread of certain aquatic weeds. It is critical that problem weeds be properly identified as a preferred food for grass carp, or they may not provide acceptable control. When stocked at low to moderate rates, grass carp will not muddy a pond as do their cousins, the common carp. They typically will not disturb the nests of other fish (bass and bream), and they are not predatory, so there is no concern about their eating desirable sport fish.

Once carp reach 20 to 30 pounds, their effectiveness as a weed control agent is diminished, since their food consumption is reduced and they are not growing as rapidly as do the smaller fish. Thus, periodic restocking (5- to 7-year rotation) may be required for permanent weed control. This, however, still represents a substantial cost savings over the use of chemicals, in many situations.

Although grass carp sometimes take on off-flavors from their diets of aquatic plants, their flesh is firm and they do not have excessive intramuscular bones. Many consider them to be excellent table fare!

Photo Gallery

Weeds Indentified on the Lake

These are weeds that have been identified by the San Jacinto River Authority as potentially spreading throughout the lake and your shoreline.

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HYDRILLA

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BUSHY POND WEED

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GIANT SALVINIA

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WATER HYACINTH

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ILLINOIS POND WEED

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Musk Grass

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Wild Celery

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Water Issues

Lake Conroe will be providing water to Montgomery County by 2015:

  • Montgomery County needs water.  Our County is growing rapidly and growth requires water.
  • Virtually all of Montgomery County’s residential water today comes from groundwater in our aquifer via water wells.
  • Our aquifer has been overused and cannot be allowed to decrease to a level where it endangers that the aquifer will never be able to “recharge” itself.  The LSGCD has concluded that the County can no longer draw greater than 64,000 acre feet of water annually from the aquifer, and that any water needs in excess of this must come from surface water (such as Lake Conroe).  The U.S. Geological Service is releasing a report before year end which addresses how fast our aquifer is “recharging” itself, and this report will provide data to support (or modify) assumptions made by LSGCD.
  • 2015 is the year in which the County will no longer be allowed to draw greater than 64,000 acre feet of water annually from groundwater in our aquifer via water wells.
  • In 2015, all County water needs in excess of 64,000 acre feet per year will come from Lake Conroe.  Based on current water usage and estimated population growth in the County, water use in the County will approximate 87,000 acre feet annually.  The shortfall of 23,000 acre feet (87,000 projected less 64,000 allowed) will equate to about 1 foot of water per year from Lake Conroe(since Lake Conroe covers 23,000 acres and we’ll have a 23,000 acre feet shortfall, the math equates to 1 foot).
  • The one foot of Lake Conroe water will be drawn annually from 2015 to 2024.  Based on estimated population growth and ignoring alternatives (see “Alternatives” below), two feet of Lake Conroe water will be drawn annually from 2025 to 2034; three feet drawn 2035 to 2044; and four feet drawn 2045 and beyond.  The maximum allowable annual draw from Lake Conroe has been set by The State of Texas at 100,000 acre feet.
  • A water treatment plant will be built below the dam on Lake Conroe and pipelines connected from that water treatment plant to various locations including, but not limited to, Conroe and The Woodlands.  Planning and construction will commence shortly so as to meet the mandated 2015 groundwater reduction deadline.  The water treatment plant will be built in units called “trains”, and additional “trains” will be added as additional water is required in each ten year interval described above.  The estimated cost of “Phase 1” (2015 operational date) is $400 million.  The estimated cost of “Phases 1 thru 4” (2045 operational date) is $2.8 billion.  Do not think the construction of the water treatment plant is an option.  This construction is a certainty, and only the amount of water needed in the future will dictate the number of “trains” needed and the final cost.