Comparisons of Estimates of Annual Exceedance-Probability Discharges for Small Drainage Basins in Iowa, Based on Data through Water Year 2013, TR-678, 2015

Traditionally, the Iowa Department of Transportation has used the Iowa Runoff Chart and single-variable regional-regression equations (RREs) from a U.S. Geological Survey report (published in 1987) as the primary methods to estimate annual exceedance-probability discharge (AEPD) for small (20 square miles or less) drainage basins in Iowa. With the publication of new multi- and single-variable RREs by the U.S. Geological Survey (published in 2013), the Iowa Department of Transportation needs to determine which methods of AEPD estimation provide the best accuracy and the least bias for small drainage basins in Iowa. Twenty five streamgages with drainage areas less than 2 square miles (mi2) and 55 streamgages with drainage areas between 2 and 20 mi2 were selected for the comparisons that used two evaluation metrics. Estimates of AEPDs calculated for the streamgages using the expected moments algorithm/multiple Grubbs-Beck test analysis method were compared to estimates of AEPDs calculated from the 2013 multivariable RREs; the 2013 single-variable RREs; the 1987 single-variable RREs; the TR-55 rainfall-runoff model; and the Iowa Runoff Chart. For the 25 streamgages with drainage areas less than 2 mi2, results of the comparisons seem to indicate the best overall accuracy and the least bias may be achieved by using the TR-55 method for flood regions 1 and 3 (published in 2013) and by using the 1987 single-variable RREs for flood region 2 (published in 2013). For drainage basins with areas between 2 and 20 mi2, results of the comparisons seem to indicate the best overall accuracy and the least bias may be achieved by using the 1987 single-variable RREs for the Southern Iowa Drift Plain landform region and for flood region 3 (published in 2013), by using the 2013 multivariable RREs for the Iowan Surface landform region, and by using the 2013 or 1987 single-variable RREs for flood region 2 (published in 2013). For all other landform or flood regions in Iowa, use of the 2013 single-variable RREs may provide the best overall accuracy and the least bias. An examination was conducted to understand why the 1987 single-variable RREs seem to provide better accuracy and less bias than either of the 2013 multi- or single-variable RREs. A comparison of 1-percent annual exceedance-probability regression lines for hydrologic regions 1–4 from the 1987 single-variable RREs and for flood regions 1–3 from the 2013 single-variable RREs indicates that the 1987 single-variable regional-regression lines generally have steeper slopes and lower discharges when compared to 2013 single-variable regional-regression lines for corresponding areas of Iowa. The combination of the definition of hydrologic regions, the lower discharges, and the steeper slopes of regression lines associated with the 1987 single-variable RREs seem to provide better accuracy and less bias when compared to the 2013 multi- or single-variable RREs; better accuracy and less bias was determined particularly for drainage areas less than 2 mi2, and also for some drainage areas between 2 and 20 mi2. The 2013 multi- and single-variable RREs are considered to provide better accuracy and less bias for larger drainage areas. Results of this study indicate that additional research is needed to address the curvilinear relation between drainage area and AEPDs for areas of Iowa.

Gaming Revenue Report, August 2015

Gaming revenue report from Department Inspect

Gaming Revenue Report, October 2015

Gaming revenue report from Department Inspect

Gaming Revenue Report, July 2015

Gaming revenue report from Department Inspect

Gaming Revenue Report, September 2015

Gaming revenue report from Department Inspect

2011 Annual Report for Appropriations from the Rebuild Iowa Infrastructure Fund and Revenue Bonds Capitals II Fund to the Watershed Improvement Fund

The Watershed Improvement Fund and the Watershed Improvement Review Board (WIRB) were created in 2005. This statute is now codified in Iowa Code Chapter 466A. The pmpose of the Watershed Improvement Fund is to enhance the water quality and flood prevention efforts in the state through a variety of impairment-based, locally­ directed watershed improvement projects. These projects are awarded grants through a competitive application process directed by the WIRB. Appropriations to the Fund do not revert. Interest earned on the moneys on the Fund are also retained in the Fund and are used to fund projects or pay per diem and expenses of the WIRB members. In state fiscal years 2009 (SFY2009) and 2010 (SFY2010), the Watershed Improvement Fund was appropriated $5,000,000 from the Rebuild Iowa Infrastructure Fund (RIIF). In SFY2011, the Watershed Improvement Fund was appropriated $2,000,000 from the Revenue Bonds Capitals II Fund (RBC2).

2012 Annual Report for Appropriations from the Rebuild Iowa Infrastructure Fund and Revenue Bonds Capitals II Fund to the Watershed Improvement Fund

The Watershed Improvement Fund and the Watershed Improvement Review Board (WIRB) were created in 2005. This statute is now codified in Iowa Code Chapter 466A. The purpose of the Watershed Improvement Fund is to enlmnce the water quality and flood prevention efforts in the state through a variety of impairment-based, locally­ directed watershed improvement projects. These projects are awarded grants through a competitive application process directed by the WIRB. Appropriations to the Fund do not revert except for the Capital Revenue Bonds II (RCB2) appropriation. Interest eamed on the moneys on the Fund are also retained in the Fund and are used to fund projects or pay per diem and expenses of the WIRB members. Starting July 1, 2012, the Fund is also receiving Animal Agriculture Compliance Fund Penalties. In state fiscal years 2009 (SFY2009) and 2010 (SFY2010), the Watershed Improvement Fund was appropriated $5,000,000 from the Rebuild Iowa Infrastructure Fund (RIIF). In SFY2011, the Watershed Improvement Fund was appropriated $2,000,000 from the Revenue Bonds Capitals II Fund (RBC2). No appropriation was received in fiscal year 2012. In SFY 2013, the Watershed Improvement Fund was appropriated $1,000,000 from the RIIF.

2013 Annual Report for Appropriations from the Rebuild Iowa Infrastructure Fund and Revenue Bonds Capitals II Fund to the Watershed Improvement Fund

The Watershed Improvement Fund and the Watershed Improvement Review Board (WIRB) were created in 2005. This statute is now codified in Iowa Code Chapter 466A. The purpose of the Watershed Improvement Fund is to enhance the water quality in the state through a variety of impairment-based, locally-directed watershed improvement projects. These projects are awarded grants through a competitive application process directed by the WIRB. Appropriations to the Fund do not revert except for the Capital Revenue Bonds II (RCB2) appropriation. Interest earned on the moneys on the Fund are also retained in the Fund and are used to fund projects or pay per diem and expenses of the WIRB members. Starting July 1, 2012, the Fund is also receiving Animal Agriculture Compliance Fund Penalties. In state fiscal years 2009 (SFY2009) and 2010 (SFY2010), the Watershed Improvement Fund was appropriated $5,000,000 from the Rebuild Iowa Infrastructure Fund (RIIF). In SFY2011, the Watershed Improvement Fund was appropriated $2,000,000 from the Revenue Bonds Capitals II Fund (RBC2). No appropriation was received in fiscal year 2012. In SFY 2013, the Watershed Improvement Fund was appropriated $1,000,000 from the RIIF.

2014 Annual Report for Appropriations from the Rebuild Iowa Infrastructure Fund and Revenue Bonds Capitals II Fund to the Watershed Improvement Fund

The Watershed Improvement Fund and the Watershed Improvement Review Board (WIRB) were created in 2005. This statute is now codified in Iowa Code Chapter 466A. The purpose of the Watershed Improvement Fund is to enhance the water quality in the state through a variety of impairment-based, locally-directed watershed improvement projects. These projects are awarded grants through a competitive application process directed by the WIRB. Appropriations to the Fund do not revert except for the Capital Revenue Bonds II (RCB2) appropriation. Interest earned on the moneys on the Fund are also retained in the Fund and are used to fund projects or pay per diem and expenses of the WIRB members. Starting July 1, 2012, the Fund is also receiving Animal Agriculture Compliance Fund Penalties. In state fiscal years 2009 (SFY2009) and 2010 (SFY2010), the Watershed Improvement Fund was appropriated $5,000,000 from the Rebuild Iowa Infrastructure Fund (RIIF). In SFY2011, the Watershed Improvement Fund was appropriated $2,000,000 from the Revenue Bonds Capitals II Fund (RBC2). No appropriation was received in fiscal year 2012. In SFY 2013, the Watershed Improvement Fund was appropriated $1,000,000 from the RIIF.

2015 Annual Report for Appropriations from the Rebuild Iowa Infrastructure Fund and Revenue Bonds Capitals II Fund to the Watershed Improvement Review Fund

This is the annual appropriations report submitted on behalf of the Watershed Improvement Review Board (WIRB).