TANGIPAHOA RIVER, LA. ENTRANCE CHANNEL

ENVIRONMENTAL STATEMENT

1. Project description. The Tangipahoa River, La., Detailed Project Report provides for the excavation of an 8- by 100-foot navigation channel between the mouth of the Tangipahoa River and the 8-foot contour in . The lake bottom has a very gradual slope in the vicinity of the Tangipahoa River and about 1 mile of channel excavation is necessary to provide an 8-foot channel. An increase in length to approximately 13,000 feet would be required for a 10-foot channel and maintenance costs would be increased substantially by the larger channel. Frequently, boats on Lake Pontchartrain must leave the lake to avoid sudden squalls and high winds and seek a secure inland location, preferably the point from which the boat was launched. A larger channel is necessary across the lake bar than would be required inland as a result of wind action which sometimes depresses the water level as much as 2 to 3 feet. A depth of 8 feet is adequate for the anticipated traffic and is about the shallowest depth practicable to maintain with the hydraulic dredging equipment that is normally used to maintain nearby Federal project channels on other tributaries to the lake, such as the Chefuncte River, Bayou Lacombe, and Bayou Bonfouca. These dredges have 18- to 20-inch diameter discharge pipes and draw from 7 to 8 feet. After consideration of channels up to 10 feet deep and up to 125 feet wide, an 8- by 100-foot entrance channel was selected on the basis of the boats to be served and the costs for construction and maintenance of the channel.

Section 107 of the River and Harbor Act of I960, as amended by Section 310 of the River and Harbor Act of 1965, provides the authority for the construction of small river and harbor improvement projects not specifically authorized by Congress which will result in substantial benefits to navigation and which can be operated consistently with appropriate and economic use of the waters of the Nation for other purposes, when in the opinion of the Chief of Engineers such work is advisable, if benefits are in excess of the cost. The improvement is economically justified, with a benefit- cost ratio of 2.4 to 1. Currently, plans and specifications have been completed and Federal funds are available for construction.

2. Environmental setting without the project. The Tangipahoa River heads in southwest near the town of McComb and flows in a southerly direction for a distance of about 110 miles to its mouth in the northwest portion of Lake Pontchartrain. The river basin has a drainage area of about 790 square miles, and Tangipahoa River provides about cne-fifth of the total inflow into Lake Pontchartrain.

Tangipahoa River, La. Environmental Statement The project area is located within the central gulf coastal plain. Specifically, the area is located in the swamplands on the northwest shore of Lake Pontchartrain between the Pleistocene uplands and the lake. The physiographic features include the flat swamplands, sinuous river course, shell beaches along the shoreline, and the lake. Relief in the area is slight except at the shoreline where some shell middens reach a maximum of +5 feet m.s.l. (mean sea level).

The Tangipahoa River Basin is almost entirely within Tangipahoa Par;*-Sh» La., and Pike County, Miss. These two areas had a total population of 94,494 in 1960. The principal cities are Hammond, La., and McComb, Miss.

The six parishes bordering on Lake Pontchartrain— Orleans, Jefferson, St. Charles, St. John the Baptist, Tangipahoa, and St. Tammany— had a total population of 974,029 in 1960 which included most of the metropolitan area of New Orleans.

Agriculture is a major contributor to the economy of the area. Dairy products comprise over 50 percent of the value of all farm products sold. Poultry, fruits and vegetables, and horticultural and forest products are next in order of value followed by miscellaneous field crops, such as corn, sorghums, hay, cotton, and legumes. Strawberries are the major fruit crop. Nearly all of the strawberries grown in are produced in this basin and in several stream basins to the west. Pine forests occupy much of the basin and provide a large source of pulpwood and saw timber. Woodland management and reforestation are carried out over extensive areas in the basin.

Industries in and adjacent to the basin include the manufacture and processing of lumber and wood products, food and kindred products, clay products, apparel, furniture, machinery, and printing and publishing. Sand, gravel, and clay are available throughout the area, principally from beds in the Tangipahoa River.

The Tangipahoa River Basin is traversed by an excellent system -of Federal, state, and local roads, and by mainline and spur railroads. Access to the river from the heavily populated area of New Orleans and vicinity has been greatly increased by the construction of the Lake Pontchartrain Toll Causeway. The initial two-lane structure was opened to traffic in 1957. An additional two-lane stiucture was completed in 1969. Further improvement in access to the Tangipahoa River area will be provided when that part of Interstate Highway 12, now under construction between Baton Rouge and Covington, is completed. Commercial air service is available at New Orleans and Baton Rouge. Smaller airfields are located at Hammond and Covington.

Tangipahoa River, La. Environmental Statement The drainage area varies in elevation from about 200 feet m.s.l. in the headwaters to near mean sea level in the marshlands adjacent to the river at the lake. The width of the stream varies from a few feet in the upper reaches to about 200 feet near its mouth. The channel is very tortuous throughout its length. Streamflow is fairly rapid in the upper reaches but becomes tidal in the lowlands adjacent to the lake. River stages vary from 3 to 20 feet in the upper reaches and from 2 to 5 feet or more in the lower reaches from freshets. Stages in the lower reaches of the river also vary as a result of winds and tides on Lake Pontchartrain. The flood plain varies from a few hundred feet at the head of the river to an average width of about 1 mile in the lower reaches. It is relatively flat in cross section and is laced with numerous old channels and small streams. Beyond the bottomlands, which are composed mostly of woodlands, the landside rises abruptly to the adjoining hills. A fringe band of fresh water marshes is found at the mouth of the river between the bottomlands and Lake Pontchartrain.

Native vegetation of the flood plains generally consists of second growth mixed hardwoods. The overstory of the bottomlands and hillsides varies in makeup but includes oaks (numerous species) , sweetgum, beech, tupelo gum, magnolia, hickory, maple, tulip poplar, cypress, sycamore, ash, cottonwood, and pine. Primarily the understory of the same area consists of starbrush, buttonbush, ironwood, willow, holly, redbud, dogwood, sumac, and gallberry. From the mixed hardwood bottomland habitat, the vegetation composition graduates into a hardwood-pine association and upon reaching the hilltop a pure pine or pine-hardwood climax is dominant. Typical vegetation in the fresh water marshes is maiden cane, water pennywort, water hyacinth, pickerelweed, alligatorweed, and bulltor.gue.

The forest,marsh and water areas provide varied and highly productive habitat for game and furbearing animals and waterfowl. Game animals and fowl occurring in the study area include deer, rabbits, squirrel, turkey, woodcock, rails, snipe, ducks, and gallinules. Upland game associated with the agricultural and forest lands consists of quail and doves. Principal furbearing animals are mink, otter, raccoon, and opossum.

Tangipahoa River has a high fishery value and outstanding aes­ thetic characteristics in its present natural state. This stream possesses scenic beauty, fast flowing, clear, productive water that offers unique recreational opportunity. Because of the natural attributes possessed by this river, it has been designated as a "natural and scenic river" under the Louisiana Natural and Scenic River System. It is one of the few streams in Louisiana that has water of a sufficient quality to produce and support high populations of Kentucky bass. Other game fish found in the river are black bass, white and black crappie, catfish, and numerous species of

Tangipahoa River, La. Environmental Statement sunfish. Crabbing is also a popular sport in the zone of tidal influx. The river above La. Highway 22 is a praised "float-fishing" stream and is utilized by local residents as well as by sports fishermen from neighboring parishes. Because of its numerous picturesque sandbars and clean water, the upper reaches of the river are utilized for swimming, sunbathing, and picnicking at the various access points and road crossings. Below La. Highway 22 the Tangipahoa River is of sufficient size to accommodate larger inboard and outboard boats (up to 20-25 feet in length). Recreational activities include fishing, hunting, waterskiing, swimming, and boating for pleasure.

Lake Pontchartrain is a 640-square mile coastal estuary lake surrounded by urban development, marshes, and swamps. It offers a variety of recreational opportunities in the form of fishing, hunting, boating, waterskiing, swimming, sailing, picnicking, and camping. Commercial fishing and trapping activities are closely related to the lake, swamp, and marsh areas. Dredging of the shell reefs for road construction material is an important resource of the lake. All these resources are readily available to the metropolitan area of New Orleans.

Many boats are operated on the lower Tangipahoa River from La. Highway 22 (mile 15.5) to the lake. Most of these boats are transported to the river on trailers and are usually launched from the bank. Boat-launching ramps are located at the Ponchatoula Beach recreational area (mile 15) and at Lee Landing (mile 8.7). Both are used extensively during the boating season. The ramp at Lee Landing is the most important since it serves the many camp owners between Lee Landing and the mouth of the river. Furnished cottages are available for rental at the Ponchatoula Beach development. They remain occupied almost continuously during the summer season. Families renting these cottages usually bring boats for use on the river. Small outboard motorboats are also available for rental and many owners of trailer-borne boats use the boat-launching facility. There are also 76 camps located along the river which are accessible only by water. A survey of the area showed that about 2,555 inboard and 27,924 outboard boat-days are expended on the Tangipahoa River annually. The river is not used for commercial purposes at this time; consequently, no terminal or transfer facilities exist.

Problems associated with the study area are minor and will require very little corrective action. As stated earlier, many small boats are operated on the lower Tangipahoa River from (mile 15.5) to Lake Pontchartrain. The mouth of the river is blocked by a sandbar in Lake Pontchartrain, created by wave action and littoral currents in the lake, which limits the . controlling depth in the entrance channel to about 1 to 2 feet at mean low gulf level and hinders access to and from the river except during high tides. Adequate depths (exceeding 5 feet) exist from

Tangipahoa River, La. Environmental Statement the bar at the mouth to about 1 mile above the Louisiana Highway 22 bridge east of Ponchatoula, La., a distance of approximately 16.5 river miles. Periodic clearing and snagging operations are necessary to keep the navigable part of the river free from fallen trees and snags. The bottom of Lake Pontchartrain in the project area consists primarily of Pleistocene clay and varies in depth from 2 feet near the shoreline to 8 feet about 1 mile off shore.

The existing project for navigation on the Tangipahoa River, authorized in 1880 and completed in 1884, provides for improvement, without dredging, by removing overhanging trees, snags, and obstructions a distance of about 53 1/2 miles above the mouth. No other naviga­ tion improvements have been made on the Tangipahoa River by Federal or non-Federal agencies.

The Tangipahoa River is not expected to change from its present condition in the foreseeable future in that it is designated for preservation under Louisiana's Natural and Scenic River System. Implementation of the recommended plan will not alter the river other than providing a safe entrance channel for the boating public.

3- The environmental impacts of the proposed action. The existing environmental setting will undergo minor physical alterations as a result of the proposed action. It will be necessary to excavate aPPr°ximately 225,000 cubic yards of bar and lake bottom clay materials in order to provide a navigation channel 8 feet deep and 100 feet wide at the entrance of Tangipahoa River. The channel will extend out to the 8-foot contour in Lake Pontchartrain and will have a total length of 1.07 miles. The channel will be excavated using hydraulic dredge equipment. Spoil area will’be on the east side of the proposed channel with the inner limit of spoil discharge being no closer than 1,500 feet to the centerline of the channel. No rights-of-way will be required on land nor will any spoil areas on land be required at this time. It is estimated that construction can be accomplished in approximately 1 1/2 months. Maintenance dredging will be required about every 3 years. The mild climate and freedom from icing on the Tangipahoa River result in a boating season which extends throughout the year. An access channel into" Lake Pontchartrain will increase greatly the attractiveness of the Tangipahoa River. New fishing and hunting areas, which cannot now be reached by small boats, will be opened to the present fleet and owners of vessels from other areas will be actracted by the excellent fishing, hunting, and scenic beauty of the river. The Lake Pontchartrain Causeway, which provides a fast, convenient route between the north and south shores of Lake Pontchartrain, encourages many owners of trailer-bcme boats and weekend visitors to utilize' the north shore of the lake. Many of these visitors will use their boats on the Tangipahoa River. Many of the cruisers from the marinas on the south shore of Lake Pontchartrain will be used to visit

Tangipahoa River, La. Environmental Statement the river when an access channel is available. Improvement of the river to provide an access channel to Lake Pontchartrain will enhance the recreational value of the stream, and will result in a great increase in use of the waterway. The major use of an improved waterway, however, will be by the recreational craft based in the surrounding parishes. An 8- by 100-fcot channel through the bar will be adequate for existing and prospective traffic and will provide safe access for boats that are required to leave the lake during inclement weather and high winds which depress and/or raise the water level in the lake as much as 2 to 3 feet at times. The Tangipahoa River is capable of furnishing a safe harbor during periods of unfavorable boating conditions. Local interest is required to furnish necessary mooring facilities and utilities including a public landing with suitable supply facilities.

Insignificant adverse effects will be associated with the con­ struction of the plan of improvement. Minimal impacts will be imposed on the fishery resources of Lake Pontchartrain by the dredging and spoiling activities. Hydraulic dredging operations will cause increased turbidity of the lake waters in the immediate vicinity of the construction. Spoil disposal within the lake will also decrease water quality by introducing a sediment load to the waters adjacent to the spoiling area. An area of about 34 acres (240 feet in width and the length of the channel) will be required for spoil placement. About 13 acres of water bottom will be required for channel construction. Increased turbidity and disruption of the aquatic habitat as a result of construction activities will have a temperary and minor effect upon the fishing activity of the area. The major detrimental affect is related to the disruption of the normal activities of the aquatic life rather than a direct loss of life or habitat by the resources. The dredging operation will be accomplished during a period of lew flow in the Tangipahoa River to reduce the spread of turbid waters *«..! during late fall or early winter so as net to interfere with r r r u t t m , activities.

^The adverse effects of the environmental impacts, as stated herein, are not conducive to remedial, protective, or mi *igstten measures. Introduction of the spoil into the laVe, rather than on land, is considered a protective measure to ret cur •.* t of the area. Spoiling on land would induce a more diverse *rd advert* effect to the environmental e.fronts which would have h«d luatir; effects extending over a long*r period of time than the selected pis* of action. r

Contractors will exorcist care in the handling and of hazardous materials to prevtr.t accidental spillage cr would result in pollution. Sanitary facilities wilt he j r to adequately dispose of domes.tic wastes fer rrnfrr-»,* r«• *;*h ft and state water pollution control regulations. Care will be taken during excavation to keep turbidity and siltation at the lowest level possible and minimize the impacts to the aquatic life.

No known historical or archaeological sites are endangered by the proposed project.

4. Any adverse environmental effects which cannot be avoided should the project be implemented. Approximately 47 acres of the lake bottom will receive some degree of alteration during the construc­ tion and subsequent maintenance of the proposed navigation improvement.

The unavoidable adverse effects are simply a temporary disruption of the existing environmental setting in a very minute area when considering the area of influence in relation to the entirety of Lake Pontchartrain. The U. S. Department of the Interior, Federal Water Quality Administration, has indicated that disposal of the spoil in this manner will not be a detrimental pollutant to the lake since the area is not used by shellfish. It is the opinion of the U. S. Department of the Interior, Fish and Wildlife Service, and the Louisiana Wild Life and Fisheries Commission that fish and wildlife resources will not be materially affected by the plan of action. No indications of losses, in the form of fish and wildlife, have developed during coordination of the proposed plan; therefore, no mitigation measures are contemplated.

5. Alternatives to the proposed action. The recommended plan of improvement is considered the best plan of action in that it produces a minimal of adverse impacts to the ecological systems and still affords recreationists an opportunity to enjoy the excellent fishing, hunting, and scenic beauty of Tangipahoa River.

Disposal of spoil material on land would be an alternative to the proposed action. This alternative is not only considered more costly but would induce more adverse effects to the environmental setting than the recommended plan. Spoiling of dredge effluent on land would require retention dikes with return of waste water back to the lake or river. The plant and animal life of the land area involved would suffer losses for the.duration required for reestablishment. Dredge effluent to be rerouted back to the lake would still create a turbidity problem similar to the proposed plan. Therefore, r.o environmental advantage would be generated by inplener.ting this course of action.

The no-action alternative would retain the existing environmental setting. It would also force restrictive usage of the natural resources up-on the public, the recommended plan cf imp reverent will not impose a noticeable ch/.rqe on the aquatic life and it; will afford the touting public a navigation channel that •»■;*,! reduce risk cf

Ta-vj i | River, t4. F rvv i r ; * • * n ? c 2 31 s t c:: c;, t marine hazards as related to accidents and inclement weather as well as afford the recreating public an opportunity to utilize the natural resources of the area,

®• The relationship between local short-term uses of man's environment and the maintenance and enhancement of long-term productivity. The improved navigation channel will require the present generation to commit about 47 acres of water bottom to channel and spoil requirements. The temporary alterations will not have significant or lasting impact on the long-term productivity of the resources in the river or the lake. The project is desirable in that a deeper and wider channel will provide improved boat access for hunters, fishermen, and recreationists for the life of the project, which may be interpreted as maintaining and enhancing the long­ term utilization of the natural resources of the area, without placing undue adverse short- or long-term effects on the resources.

7* Any irreversible or irretrievable commitment of resources which would be involved in the proposed action should it be' implemented,. There are no known irrevocable uses of the natural resources, changes in land uses, destruction of archaeological or historical sites, unalterable disruptions in the eco-systems, or other effects which would curtail the diversity and range of the beneficial uses of the existing conditions associated with the proposed project. Therefore, no irreversible or irretrievable commitments resources other than labor and material resources are associated with construction of the proposed project.

8* Coordination with other agencies, a. Interested Federal, state, and local agencies were contacted in connection with the formula­ tion of the project, and the only comments received covering the environmental aspects of the project were from the Department of the Interior, Fish and Wildlife Service; the Department of the Interior, Federal Water Quality Administration; and the Louisiana Wild Life and Fisheries Commission.

b. These agencies made no requests for modifications in the project plan.

c. At a detail planning conference during preparation of construction plans and specifications, the Louisiana Department of Public Works, the Stream Control Commission of Louisiana, and the U. S. Department of the Interior, Federal Water Quality Adminis­ tration urged that dredging operations be conducted during a period of low flow in the Tangipahoa River to reduce the spread of muddied waters and that these operations be conducted in late fall or early winter so as not to interfere with recreational activities. It was agreed that the dredging operations would be conducted during September through January.

Tangipahoa River, La. Environmental Statement d. In order to assure coordination with other interested agencies the District Engineer at New Orleans, in September 1970, corresponded with the agencies listed below. The comments received from the U. S. Department of Interior, Fish and Wildlife Service on 17 September 1970 concerning the Tangipahoa River are attached. Since replies have not been received from the other agencies, it is presummed that the proposed construction plan is satisfactory from their view points.

AGENCIES CONTACTED

1. U. S. Department of Interior, Bureau of Mines 2. U. S. Department of Interior*Bureau of Outdoor Recreation 3. U. S. Department of Interior, Federal Water Quality Administration 4. U. S. Department of Interior, Fish and Wildlife Service 5. U. S. Department of Interior, Geological Survey 6. Louisiana Department of Public Works 7. Louisiana Parks and Recreation Comm. 8. Louisiana State Board of Health 9. Louisiana Wildlife and Fisheries Comm. 10. Stream Control Commission of Louisiana 11. Tangipahoa Parish Police Jury

Incl Ltr from W. L. Towns dtd 17 Sep 70

Tangipahoa River, La. Environmental Statement United States Department of the Interior FISH AND WILDLIFE SERVICE BUREAU OF SPORT FISHERIES AND WILDLIFE PEACHTREE-SEVSNTH BUILDING - ATLANTA. GEORGIA 30323

September 17, 1970

District Engineer U.S. Army, Corps of Engineers P.0. Box 60267 New Orleans, Louisiana 70160

Dear Sir:

Reference is made to your June U, 1970, letter (LWIED-PC), requesting our comments on a list of iU authorized projects pursuant to Section 102(2)(c) of the National Environmental Policy Act of 1969, P.L. 91-190. This letter transmits our comments on the five parts of an environmental statement for the Pontchartrain Basin, Tangipahoa River, Louisiana, Entrance Channel project, located on the northwest snore of Lake Pontchartrain.

The project will involve construction and maintenance of a channel 8 feet deep over a bottom width of 100 feet across the bar at the mouth of the Tangipahoa River. Project benefits were attricuted to improved access from the Tangipahoa River to Lake Pontchartrain for sport fishing and boating in your detailed project report of June 1967.

1. The environmental impact of the proposed access improvement at the mouth of the Tangipahoa River is expected to be light. Initial construction, periodic dredging, and disposal of spoil will disturb the habitat for finfish and shell fish, particularly the young age groups. Increased pollution from increased beating and general recreation may occur as a consequence of the project.

2. Adverse environmental effects which cannot be avoided should the proposal be implemented include all items listed in paragraph 1.

3. No alternatives to the proposed action are proposed.

U. Consideration of local short-term uses of man's environment and maintenance and enhancement of long-term productivity will involve several aspects regarding fish and wildlife. The deeper and wider channel will provide improved beat access for hunters, fishermen, and recreationists. On the other hand, as previously mentioned in paragraph 1,construction and maintenance will have adverse effects on fisheries resources. The proposed work will not have direct effect on that reach of the Tan­ gipahoa River north of U.S. Highway 12 which the State advocates for preservation in its wild and natural condition.

5* Irreversible and irretrievable commitments of fish and wildlife resources which will occur if the proposed action should be implemented will be minor, but involve the resource fundamental to the expected project benefits.

The opportunity to provide information for inclusion in your En­ vironmental Statement on this matter is appreciated. Please advise if we can be of further assistance.

Sincerely yours,

W. e T Towns Acting Regional Director