What You Can Do
Although Lake Pontchartrain and its surrounding area continue to face environmental challenges, the Lake and its resources have made a tremendous comeback. Much of this success is due to interested and concerned citizens who want a clean, healthy Lake and Basin for this and future generations.
Lake Pontchartrain’s restoration begins with each of us. All of our actions, both large and small, impact the Lake’s health. There are many things, some simple, some more difficult, that all of us can do to make a difference. When we stop to consider that there are 2.1 million of us living in the Pontchartrain Basin, we realize that what we each do adds up.
As citizens of the Pontchartrain Basin, we can be involved in the Lake’s recovery through our daily actions, in our communities, and by voicing our desire to protect our valuable resources. By being informed citizens who are actively involved in the effort to restore Lake Pontchartrain we can make a difference. Become a part of this exciting effort to help Save Our Lake!
Lake Pontchartrain submerged aquatic vegetation (SAV), also call underwater grass beds, constitute the Lake’s most productive underwater habitat. They provide critical shelter and food for juvenile fish and shellfish, and are responsible for about 25 percent of the lake’s annual multi-million dollar fishing industry.
Their value includes: providing habitat for fish and shellfish, preventing coastal erosion by absorbing wave energy, recycling nutrients thereby preventing algae blooms, absorbing pollutants, decreasing water turbidity by causing sediment to drop out of the water, and providing oxygen to the water.
Recent years have seen a sharp decline in the lake’s grass beds. Where grass beds once extended to a water depth of 6 feet, they retreated to a depth of approximately 2-3 feet. From 1973, they decreased by more than 50 percent. On the south shore grass beds all but disappeared sometime between 1953 and 1973 in areas where canals discharged storm water runoff into the lake. On the north shore the disappearance of the grass beds was believed to be the result of shoreline hardening projects such as the construction of concrete sea walls and riprap levees.
Recent research done by Dr. Michael Poirrier, a scientist at the University of New Orleans, presented good news about sea grasses along the north shore of the lake. His research clearly indicated that the SAV species was making a significant comeback. While the increase could be due to several factors, including higher salinities, he believed the increase would not have occurred without improved water and habitat quality. The restoration of the sea grasses is an important goal for Lake Pontchartrain and their increase is another good sign of the improving quality of the lake.
Sewage is a main source of water pollution in the Lake Pontchartrain Basin. Sewage is another name for wastewater that comes from residences, businesses, and industries. Residential wastewater comes from showers, sinks, tubs, toilets, and washing machines. Water from equipment and food products is considered industrial or commercial wastewater
Sewage on the South Shore
On the south shore sewage is carried through sewer pipes in a municipal sewage system. In the New Orleans metropolitan area, sewage travels through many miles of gravity pipes and is pumped through lift stations before ending up at a wastewater treatment plant. The treatment plant removes pollutants and harmful bacteria from the water and the treated wastewater is discharged into the Mississippi River.
In recent years, the south shore sewerage infrastructure has been greatly improved and renovated to prevent leaks and seepage into the drainage canals that lead to Lake Pontchartrain. The testing that LPBF conducts through its water quality-monitoring program has shown that water quality has improved significantly on the lake’s south shore. The sampling results demonstrate that improvements to the sewerage system have had a tremendous impact on cleaning up Lake Pontchartrain.
Sewage on the North Shore
On the lake’s north shore, wastewater within city limits also is collected by municipal sewerage systems and routed to wastewater treatment plants. Following the treatment the wastewater is discharged into local waterways, which ultimately flow into Lake Pontchartrain.
Outside of city limits on the North Shore there are other means for treating sewerage. Individual homes and many businesses are connected to small package treatment plants. Private utilities often operate these plants. Generally wastewater that is treated by these systems is discharged into local streams and rivers that empty into the lake. Where municipal or package treatment plants are not available, individual home treatment and septic systems are still used. These are found in older subdivisions and homes in more rural locations. While home treatment systems discharge into nearby ditches, septic systems avoid discharges by incorporating leach fields.
However, rapid growth and development on the north shore has led to sewerage problems. Sewerage discharges frequently occur from overburdened wastewater treatment plants or in other cases poorly maintained and improperly operating home septic and mechanical treatment systems. The situation has resulted in a serious decline in water quality of the north shore’s waterways and along the lake’s north shore.
LPBF is attempting to address these sewerage issues through increased water quality monitoring and through its sub-basin program which seeks to innovatively address the many issues impacting the north shore water quality
Oil and Natural Gas Drilling
In the early 1990’s addressing the hazards of poor operations, the Foundation requested that the State Mineral Board place a moratorium on all new oil and gas drilling in Lake Pontchartrain. After extensive investigations, the Mineral Board agreed that expanded operations were not prudent and in 1992, a moratorium went into effect. At that time, over 20 abandoned oil and gas structures stood in various stages of dilapidation in Lake Pontchartrain. Fourteen structures were active.
The Mineral Board also addressed the problem of abandoned oil and gas wells and in 1995 the state began removing abandoned structures from the lake. Today, when a structure is decommissioned, it is promptly removed from the lake.
The mineral board reviewed the moratorium in 1995, 1996, 1998 and in 2000. In 1995, 1996, and 1998, the moratorium was extended one, two, and two years respectively. In 2000, the Mineral Board stated that it considers the lake to be a sensitive are and extended the moratorium indefinitely.
Algae Bloom and Nutrients
Nutrients in coastal systems is a continuing and widespread problem because of the often multiple undesirable consequences, such as: algal blooms, loss of seagrass habitat, low bottom-water oxygen, and fisheries losses. The 1997 opening of the Bonnet Carré Floodway on the southwest shore of Lake Pontchartrain alleviated the flood threats to New Orleans, but also created a massive algal bloom that prompted health advisories by the LDHH. Development on the north shore of Lake Pontchartrain and control of urban run-off are additional issues related to water quality, not only in Lake Pontchartrain, but also in the entire watershed.
Nutrients in the Lake may come from rivers, the atmosphere, urban runoff, leakage through the Bonnet Carré Spillway when the River is at high water levels, or from the diversion of Mississippi River water through the spillway into Lake Pontchartrain. Although intrusion of water from the Mississippi River is an intermittent factor, it appears to cause dramatic changes in the Lake's ecology.
The majority of nitrogen loading to Lake Pontchartrain in an average year comes from river discharge on the north shore of Lake Pontchartrain. When opened the Bonnet Carré Floodway delivers many times more nitrogen in a few months than the total of the nitrogen loading in an average year with additional input as a result of significant leakage during normal high water stages. All of the nitrogen in the diverted water passes through the spillway and into Lake Pontchartrain. Management of nutrient discharge into the watershed is a feasible proposition even with the urban expansion on the northern shore of the Lake. The consequences nitrogen loadings resulting from population growth on the north shore of Lake Pontchartrain can be compensated for by rather rudimentary sewerage treatment of non-point sources, from treatment or diversion of pumped urban runoff, and by sealing the leakage of water passing through the Bonnet Carré Spillway.