Lottery Action, August 25-September 7, 2003, Vol. 10, no. 17

Iowa Lottery Authority Retailer Information Newsletter

Characteristics of Chemical Treated Roadway Surfaces, HR-33, 1963

Iowa Highway Commission Project HR-33, "Characteristics of Chemically Treated Roadway Surfaces", was investigated at the Iowa Engineering Experiment Station under Project 375-S. The purpose of the project as originally proposed was to study the physical and chemical characteristics of chemically treated roadway surfaces. All chemical treatments were to be included, but only sodium chloride and calcium chloride treated roadways were investigated. The uses of other types of chemical treatment were not discovered until recently, notably spent sulfite liquor and a commercial additive. Costs of stabilized secondary roads in Hamilton County averaged $4300.00 per mile even though remanent soil-aggregate material was used. The cost of similar roads in Franklin County was $4400.00 per mile. The Franklin County road surfaces were constructed entirely from materials that were hauled to the road site. Costs in Butler County were a little over $3000.00 per mile some eight years ago. Chemical investigations indicate that calcium chloride and sodium chloride are lost through leaching. Approximately 95 percent of the sodium chloride appears to have been lost, and nearly 65 percent of the calcium chloride has disappeared. The latter value may be much in error since surface dressings of calcium chloride are commonly used and have not been taken into account. Clay contents of the soil-aggregate-chemical stabilized roads range from about 6 to ll percent, averaging 8 or 9 percent. The thicknesses of stabilized mats are usually 2 to 4 inches, with in-place densities ranging from 130 to 145 pcf. Generally the densities found in sodium chloride stabilized roads were slightly higher than those found in the calcium chloride stabilized roads.

07017-006 Little Clear Lake Watershed Final Report

Little Clear Lake is a 162 acre natural lake located in the western part of Pocahontas County. The lake has a 375 acre watershed that is gently rolling with nearly 84% of the watershed in row crop production. The lake is listed on the Iowa DNR’s impaired waters list due to nutrients, siltation and exotic species (purple loosestrife). These impairments have been verified with in-lake monitoring and landowner conversations as well as watershed modeling. The watershed models estimates that the average sheet and rill erosion is 1.74 tons/acre/year and sediment delivery is .12 tons/acre/year with a total of 44 tons/year being delivered to Little Clear Lake. The goal of the Little Clear Lake Watershed Protection Plan is to (1) reduce sediment delivery to Little Clear Lake by 60%, or 26.5 tons annually, by installing best management practices within the watershed. Doing this will control nearly 100% of the of the lake’s drainage area; and (2) initiate an information and education campaign for residents within the Little Clear Lake watershed which will ultimately prepare the residents and landowners for future project implementation. In an effort to control sediment and nutrient loading the Little Clear Lake Watershed Protection Plan has included 3 sediment catch basin sites and 5 grade stabilization structures, which function to stabilize concentrated flow areas.

1240-017 Little Bear Creek Watershed Final Report

Little Bear Creek is a 21.79 mile Class A1 and B (WW2) warm water stream that encompasses approximately 29,202 acres in northern Poweshiek County. The lower 8.4 mile segment is listed as biologically impaired on both the IDNR 2008 303(d) list and 2010 303(d) draft list. A RASCAL assessment and landowner survey was completed through a development grant in 2011, and these assessments indicate that erosion and sediment delivery from cropland, lack of adequate buffers along the stream channel, and streambank conditions contribute significant sediment delivery to the stream, likely resulting in the impairment. An estimated 36,544 tons of sediment are delivered to the stream annually. A total of 11,075 acres (38%) of the watershed are high priority areas or land with sediment delivery rates greater than one. Our goal over 15 years is to install Best Management Practices (BMPs) and increase public education in order to reduce sediment and phosphorus delivery by 25% and decrease priority areas by 15%. More specific objectives for this WIRB project are to 1) Reduce annual sediment delivery by roughly 16.3% or 1,058 tons and associated phosphorus delivery by 1,375 pounds and 2) Develop an information and education program aimed at producers and residents within the headwaters of Grant and Chester townships, which account for 18% of the watershed's priority areas. The SWCD proposes to utilize 50% EQIP funds and 25% WIRB funds toward rural BMPs, and 75% WIRB funds toward urban BMPs received through this application.