Delaware Appoquinimink River (RCWP 2)

The project addressed high nutrient concentrations causing advanced eutrophication in Silver Lake, Noxontown Pond, Wiggins Mill Pond, and Shallcross Lake. The principal water uses of these water bodies are primary and secondary contact recreation, maintenance and propagation of fish and aquatic life, industrial and agricultural water supply, drainage, navigation (tidal portion), and passage of anadromous fish. Silver Lake has been closed to primary contact recreation due to bacterial contamination. Noxontown Pond has been impaired by excessive algae growth, inhibiting its use for boating. Algae in Silver Lake has caused a decline in desirable fish species populations. Fish kills have occurred in several of the lakes.

The objective of the Appoquinimink River project was to install best management practices (BMPs) in order to reduce erosion and nutrient transport, decrease nutrient applications to cropland, and properly manage animal waste. The BMP emphasized in the project was the conversion of row crop cultivation to no-till. Pesticide and fertilizer management were also promoted through the Rural Clean Water Program (RCWP) project.

The critical area (13,000 acres) was defined based on soil erosion rates, the presence of gully erosion, concentration of animal wastes 1,500 feet or less from a stream, and the need for better farm management with respect to application of fertilizer, pesticides, and animal wastes. The implementation goal was to treat 9,750 acres of the critical area.

A water quality monitoring program included storm event sampling conducted seasonally in Noxontown Pond, Silver Lake, and Shallcross Lake. However, baseline data for Silver Lake and Noxontown Pond are lacking. Ground water monitoring was added in 1984 to determine to what extent, if any, the installation of BMPs was affecting ground water quality.

Producer participation was excellent, with 60% of the farmers, representing 87% of the critical area, participating in the project. Of the 130 farms in the watershed, 76 were under contract through the RCWP project. Over 11,000 acres in the critical area were treated to reduce nonpoint source (NPS) pollution from agricultural activities.

An unexpected reaction to the project was that farmers outside the project area were upset that they were ineligible to participate in the RCWP project.

Through the RCWP project, no-till acreage was increased from about 50% of the cropland to 90% in the project area. In addition, farmers reduced pesticide use; planted cover crops to reduce winter runoff; and installed grassed waterways, filter strips, and other measures.

Significant reductions in soil erosion and improved fertilizer and pesticide management practices have lowered the level of suspended solids in the river by 60%. In one of the ponds, monitoring showed that sediment levels have declined by 90% and total phosphorus has decreased by 65%.

The Appoquinimink River project combined excellent inter-agency cooperation and an effective information and education (I&E) program with a farm community having a strong interest in the RCWP project. The water quality monitoring program was handicapped by lack of pre-project baseline data; however, a significant reduction in suspended solids and phosphorus in the lakes was measured.

The benefits of the project have extended into other parts of New Castle County; most farmers in the county have voluntarily adopted no-till as their primary tillage practice. However, the use of no-till in corn production has significantly dropped due to slug damage and lack of a safe and effective pesticide control.

4.2 Project Findings, Recommendations, and Successes

4.2.1 Definition of Project Objectives and Goals

4.2.2 Project Management and Administration

4.2.2.1 Findings and Successes

Identifying "critical areas" for cost sharing is extremely important in maximizing the project dollars for water quality benefits (Carty et al., 1991).

A disproportionate percentage of project funds was earmarked for cost sharing land treatment, while insufficient funds were available for I&E and water quality monitoring programs.

Early involvement of producers in identifying the water quality problem and its source as well as deciding on and planning the project is key to a successful outcome.

Administration of the project by the Agricultural Stabilization and Conservation Service (ASCS) was effective because: 1) members of the ASC County Committee that worked with the Local Coordinating Committee (LCC) were farmers elected by their peers, bringing a strong community base of support; 2) ASCS had experience administering the Agricultural Conservation Program; and 3) ASCS was able to undertake the project without hiring new staff.

4.2.2.2 Recommendations

The National Coordinating Committee (NCC), or similar organization, should assign each member to monitor and provide support to specific projects. That person should attend the State Coordinating Committee (SCC) and LCC meetings of her/his projects at least once a year to help facilitate inter-project communication and information-sharing nationwide.

Appropriate reporting is necessary to provide feedback to project staff, funding agencies, and the public and to motivate agency staff to meet project goals. However, water quality project paper work should be streamlined to avoid excess reporting and documentation. Reporting requirements for the entire project period should be clearly outlined at the beginning of the program (Carty et al., 1991).

It may be helpful for SCC members to attend the meetings of other project SCCs on occasion to help facilitate sharing of resources and solutions among projects nationwide.

Local and state agencies should receive adequate advance notice of water quality program eligibility to enhance sound planning and selection of projects with a good possibility of success.

4.2.3 Information and Education

4.2.4 Producer Participation

4.2.5 Land Treatment Implementation, Tracking, and Evaluation

4.2.5.1 Findings and Successes

One-to-one contact with farmers by SCS and the Cooperative Extension Service (CES) was critical to the success of the project.

Although producers have experienced some problems with slugs in corn crops under conservation tillage due to a lack of an effective and safe pesticide, conservation tillage is still the BMP of choice for sediment control and nutrient reduction.

Projects that rely on management BMPs need specialists for effective implementation (e.g., pest management, weed control, fertilizer use). Technology transfer of management BMPs from farm to farm is critical for overall project success.

Producers installing conservation measures under the Section 208 program provided a favorable lead-in for the RCWP.

Most farmers report using soil tests to help plan for nutrient crop needs. In addition, most farmers side-band rather than broadcast fertilizer at planting and apply most nitrogen after crops are growing (split application), when crop uptake is greatest.

The use of scouting in association with pesticide management has resulted in a reduction of the amount of pesticides applied in the project area.

An innovation on a BMP developed in this project is the use of rock pads during construction of waterways to keep gullies from moving up a waterway.

4.2.5.2 Recommendations

Maintenance requirements should be clearly defined in the contract with the producer. Follow-up with the participant is necessary to ensure maintenance throughout the practice life span. (Carty et al., 1991)

Additional technical help with management practices (fertilizer, pesticide management, tillage) is very helpful in the field (Carty et al., 1991).

The economics of growing crops and the costs of implementing practices to improve water quality need to be constantly assessed in order to continue the process of identify and implementing practices that both reduce agricultural NPS pollution and are affordable and acceptable to producers.

Use of annual aerial photographs could assist in tracking of land use and BMP installation.

4.2.6 Water Quality Monitoring and Evaluation

4.2.6.1 Findings and Successes

The water quality monitoring program results show that BMPs have decreased the total phosphorus and total suspended solids concentrations in the Appoquinimink watershed.

Voluntary programs for BMP implementation have resulted in conservation tillage becoming an accepted practice for many farmers. Since BMPs were installed, however, orthophosphate concentrations (as a proportion of total phosphorus concentrations) have increased in the watershed and BMPs have failed to decrease downstream nitrogen loading.

The project lacked strong pre-project baseline data and the monitoring program would have been more useful if extended to 10 to 15 years.

Delivery of suspended solids and nutrients from agricultural lands to surface streams has declined 90% from pre-RCWP levels. The delivery of total phosphorus to the stream has shown a similar decline. Both filtered and unfiltered total phosphorus have been reduced more than 60% from pre-RCWP levels. Orthophosphorus concentrations, however, increased somewhat over the first years of the study before declining to about 65% of pre-RCWP levels. Nitrogen loads to the stream have declined less than 25% from pre-project levels.

Reduced suspended solids concentrations, and hence increased water clarity, have resulted in significant increases in algal growth in the downstream ponds. Nutrient concentrations have not varied significantly over the last four years of the project, indicating that pond sediments contribute sizable quantities of nutrients to pond waters. Water quality in the ponds can still be described as enriched.

4.2.6.2 Recommendations

All land use activities in the watershed should be identified and accounted for in the monitoring program, particularly when such activities are located immediately upstream of a monitoring station (Carty et al., 1991).

Funding should be made available for adequate pre-project monitoring and for an extended during and post-project period in order to maximize chances of documenting the effects of land treatment implemented.

4.2.7 Linkage of Land Treatment and Water Quality

4.3 Project Description

4.3.1 Project Type and Time Frame

4.3.2 Water Resource and Watershed Descriptions

4.3.2.1 Water Resource and Water Quality

4.3.2.1.1 Water Resource Type and Size

Lakes and streams in the Appoquinimink River basin

4.3.2.1.2 Water Uses and Impairments

The lakes and streams of the Appoquinimink River watershed are used for recreation by approximately half a million people who live within 20 miles of the watershed. Water uses include passive recreation (sightseeing and bird watching) and active recreation (fishing, hunting, and boating). Contact recreational uses such as swimming have been constrained by degraded water quality at Silver Lake in recent years.

4.3.2.1.3 Water Quality Problem Statement

All lakes in the Appoquinimink River basin have eutrophic conditions with dense aquatic vegetation and algal growth due to excessive nutrient concentrations. Fecal coliform bacteria standards (200/100ml) were typically violated throughout the watershed during ambient conditions.

4.3.2.1.4 Water Quality Objectives and Goals

Improve water quality in the Appoquinimink River Basin by controlling nutrient loads, sediment, bacteria, and chemical runoff from agricultural sources

4.3.2.2 Watershed Characteristics

4.3.2.2.1

Watershed Area: 30,762 acres
Project Area: 30,762 acres
Critical Area: 13,000 acres

4.3.2.2.2 Relevant Hydrologic, Geologic, and Meteorologic Factors

Mean Annual Precipitation: 45 inches

Geologic Factors: The watershed is underlain by deep sediments covering the bedrock. The surface formation consists largely of medium to coarse sands and gravels. This formation is an important water supply presently used as a potable water source for public and private supplies. The predominant soil type is deep, well-drained and medium to coarse textured. Slopes are nearly level in the uplands and steep near the stream channels.

4.3.2.2.3 Project Area Agriculture

There are about 130 farms in the project area producing primarily corn, soybeans, and vegetables. Eighty-five percent of these farms are located in the critical area. Most dairy, beef and hog operations are located along or near streams. None of the operations had animal waste treatment facilities before the RCWP project was initiated.

4.3.2.2.4 Land Use

Use      % of Project Area % of Critical Area
Cropland       64       62
Pasture/range     4        NA
Woodland    13       NA
Urban/roads    5        NA
Other
 Wetlands/Open water 14       NA

4.3.2.2.5 Animal Operations

Operation   # Farms     Total #     Total Animal
      Animals     Units
Dairy             7        945        1,323
Beef              2     293               293
Hogs            1    NA             NA
Poultry           1     70,000             2,310

4.3.2.2.6 Total Project Budget

   SOURCES   Federal     State    Farmer      Other

ACTIVITY                                  SUM

Cost Share  873,196     0     328,366           0        1,201,562
Info. & Ed.   0     0             0            0          0
Tech. Asst.     NA      0             0            NA        NA
Water Quality  225,000     0             0           90,000        315,000
 Monitoring
SUM          1,098,196  0          328,366           90,000      $1,516,562*

 * Total does not include cost of technical assistance
Source: Carty et al., 1991

4.3.4 Information and Education

4.3.5 Producer Participation

4.3.5.1 Level of Participation

Excellent: Sixty percent of the farmers, representing 87% of the critical area, actually participated in the project. Of the 130 farms in the watershed, 76 were under contract through the RCWP project to implement water quality plans.

4.3.5.2 Incentives to Participation

Cost share rates up to 75%

Payment limit of $50,000

Strong technical assistance programs for fertilizer and pesticide management programs conducted by the CES

Perception on the part of the producers that the recommended BMPs would be economically beneficial

A eutrophication problem visible to the community

4.3.5.3 Barriers to Participation

Resistance to participate in any government program by some producers

Funding limitations: the project stopped accepting applications in 1984 due to lack of funds

Producer's farm not located in the critical area

Inability of some producers to manage their share of the cost of BMP implementation

4.3.5.4 Chances of Continued Maintenance/Adoption of BMPs

Very good because farmers see the economic as well as water quality benefits of the practices. However, there has been some reduction in use of conservation tillage due to slug and weed control problems.

The use of no-till will be modified based on fuel costs (the higher fuel costs, the more no-till), the slug problem, and soil and climatic conditions (no till has a place when it is very wet or very dry).

The spillover from the project area to the rest of the county has been a major success of the project. Many farmers outside the project area wanted to participate in the project but were ineligible. Some of these producers have voluntarily adopted conservation tillage without cost share assistance through the RCWP.

4.3.6 Land Treatment

4.3.6.1 Strategy and Design

The land treatment strategy was to target management practices that would reduce soil and nutrient losses, in particular, conservation tillage and fertilizer and pesticide management.

4.3.6.2 Objectives and Goals

Reduce soil and nutrient losses from cropland

Reduce the amounts of fertilizer and pesticides applied to cropland

Implement practices to manage manure applications so as to reduce nutrient losses

The original project goal was to have 100% of the critical area (13,00 acres) under contract by the end of FY 1984 with all contracts implemented by the end of FY 1989; this goal was later revised to treatment of 9,750 critical acres.

4.3.6.3 Critical Area Criteria and Application

Criteria:

Soil erosion exceeding T value

Gully erosion (including ephemeral) is present

Concentration of animal wastes 1,500 feet or less from a stream

Need for better farm management with respect to application of fertilizer, pesticides, and animal wastes

Application of Criteria: Critical area designation for individual contracts was determined by soil conservationists using the above criteria on a field by field basis.

4.3.6.4 Best Management Practices Used

The primary BMP emphasis was on conservation tillage, fertilizer management, and pesticide management. There was some implementation of animal waste management systems, primarily manure - holding structures and calibration of manure application equipment.

BMPs Utilized in the Project *:

Permanent vegetative cover (BMP 1)
Animal waste management system (BMP 2)
Diversion system (BMP 5)
Waterway system (BMP 7)
Cropland protection system (BMP 8)
Conservation tillage system (BMP 9)
Permanent vegetative cover on critical areas (BMP 11)
Sediment retention, erosion, or water control structures (BMP 12)
Improving an irrigation and/or water management system (BMP 13) (not cost shared)
Fertilizer management (BMP 15) (not cost shared)
Pesticide management (BMP 16) (not cost shared)

* Please refer to Appendix I for description/purpose of each BMP.

4.3.6.5 Land Treatment and Use Monitoring & Tracking Program

4.3.6.5.1 Description

BMP installation was tracked and reported through annual reports. A spreadsheet was used to track each contract. Maintenance was tracked through annual status reviews. Land use changes were not formally tracked; however, major land use changes did not occur in the project area during the course of the project.

4.3.6.5.2 Data Management

Details of BMP implementation, cropping (type, acreage, and yield), fertilizer application rates (nitrogen and phosphorus), and pesticide type and application rate are kept in the New Castle County Automated Environmental Resources Information (AERI) System.

4.3.6.5.3 Data Analysis and Results

Improved fertilizer management has cut the phosphorus application rate in half compared to the pre-project period. Installation of manure holding structures allows farmers to store animal wastes for timely application to meet crop needs.

Scouting has decreased pesticide applications as well.

Quantified Project Achievements:

            Critical Area             Treatment  Goals 
Pollutant   
Source        Units  Total % Implemented         Total      % Implemented

Cropland     acres   13,000       87%                  9,750           117%
Dairies     #    7       43%           5              60%
Water       #   160      48%     80              96%

Quality Plans Source: Appoquinimink River RCWP Project, 1987. RCWP Progress Summary for Fiscal Year 1987, form RCWP 3

4.3.7 Water Quality Monitoring and Evaluation

4.3.7.1 Strategy and Design

The water quality monitoring and evaluation program was designed and conducted by the University of Delaware College of Agricultural Sciences under contract to the Water Resources Agency for New Castle County.

Storm event samples were taken seasonally in Noxontown Pond, Silver Lake, and Shallcross Lake.

Ground water monitoring was added in 1984 to determine to what extent, if any, the installation of BMPs was affecting ground water quality.

4.3.7.2 Objectives and Goals

Continue an existing physical, chemical, biological, and hydraulic monitoring program being conducted in the Noxontown Pond headwaters (sub-watershed of the Appoquinimink River basin)

Evaluate the impact of agricultural BMPs on water quality in the Appoquinimink watershed

Evaluate the impacts of improved animal waste handling, erosion and runoff control, fertilizer, and pesticide management on ground water quality

4.3.7.3 Time Frame

Wiggins Mill Pond: 1980 - 1986

Silver Lake, Shallcross Lake, and Noxontown Pond: 1983 - 1986

Ground water: 1984 - 1986

4.3.7.4 Sampling Scheme

4.3.7.4.1 Monitoring Stations

Wiggins Mill Pond: 1 station to monitor a 2,200 acre sub-watershed / Approximately 1,200 acres of this sub-watershed are in the critical area

Silver Lake, Shallcross Lake, and Noxontown Pond: 3 stations for each water body (2 within the lake and 1 at the outlet)

4.3.7.4.2 Sample Type

Grab

4.3.7.4.3 Sampling Frequency

Wiggins Mill Pond: Frequency varied from 1 to 7 samples per month / data set includes some storm flow samples

Silver Lake, Shallcross Lake, and Noxontown Pond: Monthly for baseline data / 3 storm event samples per year

4.3.7.4.4 Variables Analyzed

Wiggins Mill Pond: Biological monitoring consisting of periphyton and macroinvertebrates sampled monthly, May-October 1985-86

Silver Lake, Shallcross Lake, and Noxontown Pond: (all stations) water & air temperature, biochemical oxygen demand (BOD), chemical oxygen demand (COD), acidity, alkalinity, hardness, pH, dissolved oxygen (DO), suspended solids (SS), dissolved solids (DS), orthophosphate (OP), total phosphorus (TP), organic nitrogen, ammonia-nitrogen (NH3-N), nitrite-nitrogen (NO2-N) and nitrate-nitrogen (NO3-N), chlorophyll a, biota, and coliform, fecal coliform (FC), and fecal streptococci bacteria

Silver Lake, Shallcross Lake, and Noxontown Pond: Biological monitoring consisting of periphyton and macroinvertebrate sampled monthly (April-Nov., 1985-86)

4.3.7.4.5 Flow Measurement

Instantaneous, taken at each pond spillway whenever outflow samples were collected and in stream when samples were collected below Wiggins Mill Pond

4.3.7.4.6 Meteorologic Measurements

Precipitation: US Weather Bureau station at Middletown, near the center of the watershed

4.3.7.4.7 Other Important Water Quality Monitoring and Evaluation Information

The monitoring program lacks a baseline period for Silver Lake and Noxontown Pond.

Silver Lake, Shallcross Lake, and Noxontown Pond: Point source monitoring - monthly sampling of point source discharges are conducted to supplement information in NPDES (National Pollutant Discharge Eliminiation System) Compliance Monitoring Reports, particularly for nitrogen and phosphorus discharge loads

Wiggins Mill Pond: The dam washed out in the spring of 1979 and was restored in 1984.

Noxontown Pond was dredged in 1984 through 1985 and may have contributed to increased organic nitrogen concentrations.

4.3.7.5 Data Management

The data are managed locally.

4.3.7.6 Data Analysis and Results

Analysis:

All water quality data were initially reduced to monthly means to reduce bias introduced by variation in sample number and period. Data summaries included univariate descriptive statistics using the SAS MEANS procedure and bivariate statistics using the SAS CORR procedure.

Analyses for trends were conducted by inspection of annual and seasonal mean concentrations and loading rates, and by evaluation of correlation coefficients to determine the significance of water quality changes over time.

Results:

Significant reductions in soil erosion and improved fertilizer and pesticide management practices have lowered the level of suspended solids in the river by 60%. In one pond, sediment levels have declined by 90% and total phosphorus has decreased by 65%.

The project team reports the following water quality trends. Delivery of suspended solids and nutrients from agricultural lands to surface streams has declined 90% from pre-RCWP levels. The delivery of total phosphorus to the stream has shown a similar decline. Both filtered and unfiltered total phosphorus have been reduced more than 60% from pre-RCWP levels. Orthophosphorus concentrations, however, increased somewhat over the first years of the study before declining to about 65% of pre-RCWP levels. Nitrogen loads to the stream have declined less than 25% from pre-project levels. Increased concentrations of organics (biochemical and chemical oxygen demand) are attributable to greater proportions of cropland remaining in vegetative cover from conservation tillage; however, these levels have not increased to a point where they are a concern (Carty et al., 1991).

4.3.8 Linkage of Land Treatment and Water Quality

4.3.9 Impact of Other Federal and State Programs on the Project

The 1980 state sedimentation and erosion control law complemented RCWP in that all land disturbing activities required a plan to control off-site sediment. This included major and minor subdivision activity that occurred in the watershed (Carty et al., 1991).

Delaware's revised septic system regulations also complemented RCWP in that a site evaluation conducted by a licensed soils evaluator was required. The new standards prevent common failures encountered in the old method of total reliance on a percolation test (Carty et al., 1991).

During the project period, the Water Resource Agency developed resource protection area maps that identified recharge areas and wellhead areas in the county. Development in these areas was restricted by the county planning department (Carty et al., 1991).

4.3.10 Other Pertinent Information

4.3.11 References

Appoquinimink River RCWP Project, 1987. RCWP Progress Summary for Fiscal Year 1987, form RCWP 3.

Carty, C., J.J. Lakatosh, L.R. Irelan, B.L. Dworsky, R. Mulrooney, W. Ritter. 1991. Appoquinimink Rural Clean Water Program Ten Year Report. September 1991. Cooperators: ASCS, SCS, New Castle Conservation District, New Castle County-Water Resources Agency, CES, and the University of Delaware. 56p. plus appendices.