// source http://jsbin.com/jegumacemi

index.html

<script src="https://www.gstatic.com/charts/loader.js"></script>
<script>
  var URL = "https://docs.google.com/spreadsheets/d/1CyTpbs6OQorCEBR8ZI-hwP_pj_YF8XJz8a0qa3fugh0/edit";
  google.charts.load('current', {'packages':['gantt']});

  // Set a callback to run when the Google Visualization API is loaded.
  google.charts.setOnLoadCallback(() => {
    var query = new google.visualization.Query(URL);
    query.send((response) => {
      var data = response.getDataTable();
      data.ng[2].type = data.ng[3].type = "date";

      var chart = new google.visualization.Gantt(document.getElementById('chart_div'));

      var options = {
        // height: 275,
        gantt: {
          defaultStartDateMillis: Date.now()
        }
      };

      chart.draw(data, options);
    });
  });
</script>

<div id="chart_div"></div>
<script id="jsbin-source-html" type="text/html"><script src="https://www.gstatic.com/charts/loader.js"><\/script>
<script>
  var URL = "https://docs.google.com/spreadsheets/d/1CyTpbs6OQorCEBR8ZI-hwP_pj_YF8XJz8a0qa3fugh0/edit";
  google.charts.load('current', {'packages':['gantt']});

  // Set a callback to run when the Google Visualization API is loaded.
  google.charts.setOnLoadCallback(() => {
    var query = new google.visualization.Query(URL);
    query.send((response) => {
      var data = response.getDataTable();
      data.ng[2].type = data.ng[3].type = "date";

      var chart = new google.visualization.Gantt(document.getElementById('chart_div'));

      var options = {
        // height: 275,
        gantt: {
          defaultStartDateMillis: Date.now()
        }
      };

      chart.draw(data, options);
    });
  });
<\/script>

<div id="chart_div"></div>
</script>