function toggleSewer() {
	if (document.getElementById('overlay').style.display == 'block') { document.getElementById('overlay').style.display = 'none'; }
	else { document.getElementById('overlay').style.display = 'block'; }
	if (document.getElementById('sewerInformation').style.display == 'block') { document.getElementById('sewerInformation').style.display = 'none'; }
	else { document.getElementById('sewerInformation').style.display = 'block'; }
}