Practical Highway Design Solutions (2013)

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71 Appendix G Case examples of practical Solutions for Kentucky Transportation Cabinet PROJECT #1: NEW BRIDGES OVER LAKE BARKLEY & KENTUCKY LAKE; US 68 / KY 80 DESCRIPTION: The “Lake Bridges” project was well under way by the �me the Prac�cal Solu�ons ini�a�ve came along. However, a�er hearing about Prac�cal Solu�ons the design team felt challenged and decided to take a look at their project through a Prac�cal Solu�ons lens. The team realized that their bridge sec�on was too big. They reduced the width to a more prac�cal width, which resulted in an es�mated $140 million savings. As shown in the illustra�on below, this was accomplished by reducing the cross-sec�on from 102’6” to 74’6” segmented as follows: From To Inside shoulder width 6’0” 4’0” Travel lanes 12’0” 11’0” Outside shoulder width 12’0” 4’0” Sidewalk and bike path 12’0” 8’0” ORIGINAL TYPICAL SECTION REDUCED SECTION

72 PROJEC T # 2: BRIDGE REPLACEMENT ON KY 3459 OVER MARTIN’S FORK O F CU MBER LAND RIV ER DESCRI PTION: Thi s bridge was determined to be stru cturally defi cient (SR=14. 6) and was to b e replaced. The approa ch roa d is a rura l local ro ad with 10 ft lanes and 1 ft shoulders. The ro ad had a current A DT of 3 ,730 vehi cles p er day . A ASHTO recommends 12 ft lanes and 8 ft shoulders for rural local roadway with an AD T of th e curre nt v ol um e and a 35 mph desi gn . This would require a bri dge clear width of 40 ft to a ccommodate this recommended template. With the e xisting r oadw ay s ervi ng the area having a total width of 1 0 ft, the project tea m did not s ee the b enefit of c onstru ct ing the b ridge and approaches to t his typical full design. The right-of-way impacts would be tremen do us due to the location of buildings within the limits of the project. Due to th e width of the existing r oa dw ay and tr ying t o bet ter match what i s ther e, th e p ro ject team reques ted th at t he consultant evaluate th e effect s of using 10 ft lanes with 2 f t s ho ulders and 11 ft lanes with 4 ft shoulders and not even consi de r utilizing 12 ft lan es with 8 ft s ho ulders . The pro je ct tea m de cided to go with 10 ft l anes with 2 ft s ho ulders. Th e widt h doubles the existing bridge and approach widths at this location, the right-of-way and utility impacts are minimized and the designers were able to ti e t he approach r oadw ay widths back to existing in a shor ter distan ce , thus reducing the overall pr ojec t length and i mpacts. By selecting this de sign compa red to t he AASHTO- based design, the construction cost was reduced from $1,075,650 to $878,000, realizing a savings of $1 97, 650

73 PROJEC T # 3: ROADWAY I MP ROVEMEN T FOR 3 .23 MILE SECTION OF KY 2158 DESCRI PTION: T his improvement for a section of KY 2158 was originally slated to be a “super 2 lane” meaning using 1 2 f t lanes a nd 8 ft s ho ulders. A p orti on o f this road ha s commercial deve lo pm ent with higher traffic vol um es. Th e r em ainder of the p ro ject is residential and far m land. The project te am recognized that this was not practical. Ther efor e, th ey elec ted t o re duce the rural section to 11 ft lanes and 2 ft shoulders, which was co nsid ered appr opriate to t he context of the rural area. This decis io n resulted in a $2 .1 million savings from the original cost of $6. 6 million.

74 PROJEC T # 4: IMPROVE THE CA PACITY AND SAFET Y OF TH E INTERS ECTION OF KY 720 & HORS ESHOE BEND ROA D DESCRI PTION: As seen by the photograp h below the problem was limited visibilit y th ro ugh the intersection ar ea . T he i mp rovement p ro ject was originally develop ed as in te rsection realignment. Aft er several alignment plans were prepared, it was suggested that removing the trees at the intersection corner would provide en ou gh visibility. This option was pursued. The realignment design would have cost $780,000; tree cutting cos t $13,500.